TITLE: Herbicide Tolerance/Resistance in Plants, QB 9460PUBLICATION DATE: March, 1994ENTRY DATE: November, 1994EXPIRATION DATE: NoneUPDATE FREQUENCY: As neededCONTACT: Biotechnology Information Center(biotech@nalusda.gov)         National Agricultural LibraryDOCUMENT TYPE: TextDOCUMENT SIZE: 455K
**Herbicide Tolerance/Resistance in Plants**
                             SEARCH STRATEGY
     SET       ITEMS     DESCRIPTION            S1823HERBICID? (W) (TOLERAN? OR RESISTAN?)      S2396S1 AND PY=1991:1999      S3395S2/ENG
1                                                 NAL Call. No.: 275.29 N272EXA 1992 guide for--herbicide use in Nebraska.Lincoln, Neb. : The Service; 1992.EC - Cooperative Extension Service, University of Nebraska (92-130): 51 p.;1992.  Includes references.
Language:  English
Descriptors: Nebraska; Weed control; Herbicides; Weeds; Herbicide resistance;Conservation tillage
2                                                      NAL Call. No.: 79.8 W41Absence of a role for absorption, translocation, and metabolism indifferential sensitivity of hemp dogbane (Apocynum cannabinum) to two pyridineherbicides.Orfanedes, M.S.; Wax, L.M.; Liebel, R.A.Champaign, Ill. : Weed Science Society of America; 1993 Jan.Weed science v. 41 (1): p. 1-6; 1993 Jan.  Includes references.
Language:  English
Descriptors: Apocynum cannabinum; Clopyralid; Fluroxypyr; Herbicideresistance; Susceptibility; Absorption; Metabolism; Translocation; Weeds; Weedcontrol
Abstract:  Hemp dogbane is sensitive to fluroxypyr and tolerant to clopyralid.Absorption, translocation, and metabolism of clopyralid and fluroxypyr werestudied in hemp dogbane to determine if differences in these processes couldbe responsible for differential sensitivity. In addition, the effect of growthstage on herbicide absorption and translocation was evaluated. The14C-herbicides were applied to the adaxial side of a single leaf located nearthe midpoint of hydroponically cultured plants. Uptake of fluroxypyr was morerapid than clopyralid. At 72 h after treatment (HAT), fluroxypyr andclopyralid absorption was 62 and 38%, respectively. Clopyralid was much moremobile than fluroxypyr, with 75% of the absorbed 14C from 14C-clopyralidrecovered outside the treated leaf compared to only 45% for fluroxypyr 72 HAT.Relative to fluroxypyr, a higher percentage of 14C-clopyralid recoveredoutside the treated leaf translocated acropetally, especially when plants weretreated during the vegetative stage. Treatment during the early reproductivestage increased basipetal and reduced acropetal translocation relative to thevegetative stage. Neither herbicide was metabolized rapidly. Approximately 60and 90% of the recovered 14C was attributable to unaltered fluroxypyr andclopyralid, respectively, 72 HAT. Some differences in absorption,translocation, and metabolism between clopyralid and fluroxypyr exist, butthey cannot fully account for differential sensitivity of hemp dogbane tothese two herbicides. Differences in activity at the target site may beresponsible for differential activity of these herbicides on hemp dogbane.
3                                                     NAL Call. No.: SB951.P49Absorption and metabolism of clomazone by suspension-cultured cells of soybeanand velvetleaf.Weimer, M.R.; Balke, N.E.; Buhler, D.D.Orlando, Fla. : Academic Press; 1992 Jan.Pesticide biochemistry and physiology v. 42 (1): p. 43-53; 1992 Jan.  Includesreferences.
Language:  English
Descriptors: Glycine max; Abutilon theophrasti; Cell suspensions; Cellcultures; Metabolic detoxification; Clomazone; Absorption; Metabolism;Oxidation; Metabolites; Characterization; Herbicide resistance; Speciesdifferences; Phytotoxicity; Selectivity; Pharmacokinetics
Abstract:  Clomazone uptake and metabolism were compared in soybean andvelvetleaf suspension cultured cells utilizing either [14C]methylene-clomazoneor [14C]carbonyl-clomazone. Velvetleaf cells absorbed more clomazone thansoybean did. Cells of both species accumulated more metabolites when treatedwith [14C]methylene-clomazone than when treated with [14C]carbonyl-clomazone.Higher amounts of [14C]metabolites were present in the media of cells treatedwith [14C]carbonyl-clomazone than [14C]methylene-clomazone. Differences inuptake were due to cellular retention of the benzyl moiety and efflux of theheterocyclic moiety after cleavage of clomazone. All metabolites produced insoybean and velvetleaf cells were more polar than clomazone. No qualitativedifferences in the metabolites produced by soybean and velvetleaf wereidentified. Both soybean and velvetleaf oxidatively cleaved the clomazonemolecule and subsequently conjugated the benzyl moiety with glucose. One ofthe aglycones was identified as 2-chlorobenzylalcohol. Oxidative cleavage ofclomazone was a major metabolic reaction occurring in both the tolerant(soybean) and susceptible (velvetleaf) species.
4                                                      NAL Call. No.: SD13.C35Absorption and translocation of [14C]glyphosate in four woody plant species.Green, T.H.; Minogue, P.J.; Brewer, C.H.; Glover, G.R.; Gjerstad, D.H.Ottawa, Ont. : National Research Council of Canada; 1992 Jun.Canadian journal of forest research; Revue canadienne de recherche forestierev. 22 (6): p. 785-789; 1992 Jun.  Includes references.
Language:  English
Descriptors: Southeastern states of U.S.A.; Pinus taeda; Ilex vomitoria; Acerrubrum; Quercus rubra; Glyphosate; Tolerance; Translocation; Absorption;Leaves; Roots; Stems
Abstract:  Absorption and translocation patterns of radio-labelled glyphosate(N-(phosphonomethyl)glycine) were examined in four species of woody plants todetermine mechanisms of herbicide tolerance in species common to thesoutheastern United States. Loblolly pine (Pinus taeda L.) and yaupon (Ilexvomitoria (L.) Ait.), both tolerant to the herbicide, absorbed significantlyless glyphosate than did red maple (Acer rubrum L.) or white oak (Quercus albaL.), indicating the importance of foliar absorption as a barrier to glyphosateentry. Although herbicide absorption was similar between the sensitive whiteoak and the tolerant red maple, white oak accumulated more glyphosate in theroots than did red maple, indicating that translocation patterns alsocontribute significantly to glyphosate tolerance in some woody species.
5                                                      NAL Call. No.: 450 P692Acetolactate synthase inhibiting herbicides bind to the regulatory site.Subramanian, M.V.; Loney-Gallant, V.; Dias, J.M.; Mireles, L.C.Rockville, Md. : American Society of Plant Physiologists; 1991 May.Plant physiology v. 96 (1): p. 310-313; 1991 May.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Gossypium hirsutum; Mutants; Herbicideresistance; Phytotoxicity; Triazole herbicides; Sulfonylurea herbicides;Chlorsulfuron; Imazethapyr; Imidazolinone herbicides; Ligases; Enzymeinhibitors; Binding site; Leucine
Abstract:  Acetolactate synthase from spontaneous mutants of tobacco(Nicotiana tabacum; KS-43 and SK-53) and cotton (Gossypium hirsutum; PS-3,PSH-91, and DO-2) selected in tissue culture for resistance to atriazolopyrimidine sulfonanilide showed varying degrees of insensitivity tofeedback inhibitor(s) valine and/or leucine. A similar feature was evident inthe enzyme isolated from chlorsulfuron-resistant weed biotypes, Kochiascoparia and Stellaria media. Dual inhibition analyses of triazolopyrimidinesulfonanilide, thifensulfuron, and imazethapyr versus feedback inhibitorleucine revealed that the three herbicides were competitive with the aminoacid for binding to acetolactate synthase from wild-type cotton cultures.Acetolactate synthase inhibiting herbicides may bind to the regulatory site onthe enzyme.
6                                                      NAL Call. No.: 79.8 W41Acifluorfen tolerance in Lycopersicon.Ricotta, J.A.; Masiunas, J.B.Champaign, Ill. : Weed Science Society of America; 1992 Jul.Weed science v. 40 (3): p. 413-417; 1992 Jul.  Includes references.
Language:  English
Descriptors: Lycopersicon esculentum; Genotypes; Herbicide resistance;Acifluorfen; Absorption; Foliar uptake; Leaves; Cuticle; Waxes; Translocation;Metabolism; Ascorbic acid; Varietal susceptibility; Chlorophyll
Abstract:  Studies were conducted to determine the mechanism of acifluorfentolerance within the Lycopersicon genus. Absorption of 14C-acifluorfen was notcorrelated with tolerance. There was a negative correlation (r = -0.57)between absorption 24 h after treatment and wax density. No other surfacecharacteristic correlated with absorption. Less than 3% of absorbed 14C wastranslocated and there was no metabolism of acifluorfen. All genotypes weresusceptible to paraquat, and acifluorfen-tolerant genotypes had lower levelsof ascorbate than susceptible genotypes, implying that free radical protectantsystems were not involved in tolerance. Genotypes varied in amounts ofchlorophyll a, chlorophyll b, and total chlorophyll but the differences didnot correlate to acifluorfen tolerance.
7                                                     NAL Call. No.: SB610.W39Addressing real weed science needs with innovations.Gressel, J.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 509-525; 1992 Jul.  Literature review.  Includes references.
Language:  English
Descriptors: Weeds; Weed control; Agricultural research; Herbicides; Herbicideresistance; Pest management; Biological control; Biotechnology; Parasiticweeds; Agriculture; Literature reviews
8                                                     NAL Call. No.: SB123.P55Advances in achieving the needs for biotechnologically-derived herbicideresistant crops.Gressel, J.New York, N.Y. : John Wiley & Sons, Inc; 1993.Plant breeding reviews v. 11: p. 155-198; 1993.  Includes references.
Language:  English
Descriptors: Crops; Plant breeding; Herbicide resistance; Genes; Geneticengineering; Biotechnology; Cultivars; Weed control; Genetic resistance;Literature reviews
9                                                     NAL Call. No.: QK725.P54Agrobacterium mediated transfer of a mutant Arabidopsis acetolactate synthasegene confers resistance to chlorsulfuron in chicory (Chichorium intybus L.).Vermeulen, A.; Vaucheret, H.; Pautot, V.; Chupeau, Y.Berlin, W. Ger. : Springer International; 1992.Plant cell reports v. 11 (5/6): p. 243-247; 1992.  Includes references.
Language:  English
Descriptors: Cichorium intybus; Genetic transformation; Herbicide resistance;Chlorsulfuron; Kanamycin; Transgenics; Agrobacterium tumefaciens; Arabidopsisthaliana; Gene transfer
Abstract:  Leaf discs of C. intybus were inoculated with an Agrobacteriumtumefaciens strain harboring a neomycin phosphotransferase (neo) gene forkanamycin resistance and a mutant acetolactate synthase gene (csr1-1) fromArabidopsis thaliana conferring resistance to sulfonylurea herbicides. Aregeneration medium was optimized which permitted an efficient shootregeneration from leaf discs. Transgenic shoots were selected on rootingmedium containing 100 mg/l kanamycin sulfate. Integration of the csr1-1 geneinto genomic DNA of kanamycin resistant chicory plants was confirmed bySouthern blot hybridizations. Analysis of the selfed progenies (S1 and S2) oftwo independent transformed clones showed that kanamycin and chlorsulfuronresistances were inherited as dominant Mendelian trails. The method describedhere for producing transformed plants will allow new opportunities for chicorybreeding.
10                                                       NAL Call. No.: 30 Ad9Agronomic improvement in oilseed brassicas.Downey, R.K.; Rimmer, S.R.San Diego, Calif. : Academic Press; 1993.Advances in agronomy v. 50: p. 1-66; 1993.  Includes references.
Language:  English
Descriptors: Brassica campestris; Brassica carinata; Brassica juncea; Brassicanapus; Oilseed plants; Macroeconomics; Biotechnology; Crop yield; Cultivars;Genetic improvement; Genome analysis; Hybridization; Disease resistance;Herbicide resistance; Pest resistance; Yield components; Plant oils; Proteincontent; Seeds; Literature reviews
11                                                    NAL Call. No.: 64.8 C883Agronomic performance of sulfonylurea-resistant transgenic flue-cured tobaccogrown under field conditions.Brandle, J.E.; Miki, B.L.Madison, Wis. : Crop Science Society of America, 1961-; 1993 Jul.Crop science v. 33 (4): p. 847-852; 1993 Jul.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Transgenic plants; Lines; Herbicideresistance; Sulfonylurea herbicides; Agronomic characteristics; Geneticresistance; Chlorsulfuron; Tribenuron; Phytotoxicity; Crop yield; Crop damage;Gene expression; Genetic variation
Abstract:  Field testing of transgenic crops is an essential step towardscommercialization. This study was conducted to assess the agronomicperformance of herbicide-resistant transgenic tobacco (Nicotiana tabacum L.)lines relative to untransformed controls and to evaluate their sensitivity tosulfonylurea herbicides in a field situation. Two transgenic flue-curedtobacco lines harboring the csr1-1 gene for sulfonylurea resistance wereevaluated after application of three rates of two sulfonylurea herbicides[chlorsulfuron (2-chloro-N[(4-methoxy-6-methyl- 1,3,5 triazin-2-yl)aminocarbonyl]-aminosulfonyl]-2-thiophenecarboxylate) R9674, a 2:1 mixture ofthifensulfuron (methyl-3-[[4-methoxy-6-methyl- 1,3,5-triazin-2-ylaminocarbonyl]aminosulfonyl]-2-thiophenecarboxy- late) and tribenuron(methyl-2[[[[4-methoxy-6-methyl-1,3,5-triazin-2-yl]carbonyl]amino]sulfonyl]benzoate)]. We show that one of the lines wasresistant to 10 g a.i. ha-1 of chlorsulfuron but not to 20 g a.i. ha-1 andthat both lines were susceptible to DPX-R9674. Comparison of transgenics to anuntransformed control in the absence of herbicide treatment showed that bothtransgenics were lower yielding than tbe controls. This impairment ofagronomic performance could be attributed to any of a number of factors.Resistance to chlorsulfuron was adequate, but margins of safety need to beincreased before any farm level use of these transgenic lines can beconsidered. Selection among lines for maximum expression of the transgene andselection or backcrossing to recover the parental phenotype may furtherimprove agronomic performance.
12                                                    NAL Call. No.: SB193.F59Alfalfa germplasm with resistance to terbacil.Caddel, J.L.; Stritzke, J.F.; Anderson, M.P.; Bensch, C.Georgetown, Tx. : American Forage and Grassland Council; 1992.Proceedings of the Forage and Grassland Conference v. 1: p. 162-165; 1992.
Language:  English
Descriptors: Oklahoma; Medicago sativa; Terbacil; Herbicide resistance;Germplasm; Selection
13                                                     NAL Call. No.: 442.8 Z8Allelic mutations in acetyl-coenzyme A carboxylase confer herbicide tolerancein maize.Marshall, L.C.; Somers, D.A.; Dotray, P.D.; Gengenbach, B.G.; Wyse, D.L.;Gronwald, J.W.Berlin, W. Ger. : Springer International; 1992.Theoretical and applied genetics v. 83 (4): p. 435-442; 1992.  Includesreferences.
Language:  English
Descriptors: Zea mays; Structural genes; Alleles; Acetyl-coa carboxylase;Mutants; Mutations; Herbicide resistance; Haloxyfop; Sethoxydim; Allelism; Invitro selection; Inheritance; Semidominance; Enzyme activity
Abstract:  The genetic relationship between acetyl-coenzyme A carboxylase(ACCase; EC 6.4.1.2.) activity and herbicide tolerance was determined for fivemaize (Zea mays L.) mutants regenerated from tissue cultures selected fortolerance to the ACCase-inhibiting herbicides, sethoxydim and haloxyfop.Herbicide tolerance in each mutant was inherited as a partially dominant,nuclear mutation. Allelism tests indicated that the five mutations wereallelic. Three distinguishable herbicide tolerance phenotypes weredifferentiated among the five mutants. Seedling tolerance to herbicidetreatments cosegregated with reduced inhibition of seedling leaf ACCaseactivity by sethoxydim and haloxyfop demonstrating that alterations of ACCaseconferred herbicide tolerance. Therefore, we propose that at least three, andpossible five, new alleles of the maize ACCase structural gene (Acc1) wereidentified based on their differential response to sethoxydim and haloxyfop.The group represented by Acc1-S1, Acc1-S2 and Acc1-S3 alleles, which hadsimilar phenotypes, exhibited tolerance to high rates of sethoxydim andhaloxyfop. The Acc1-H1 allele lacked sethoxydim tolerance but was tolerant tohaloxyfop, whereas the Acc1-H2 allele had intermediate tolerance to sethoxydimbut was tolerant to haloxyfop. Differences in tolerance to the two herbicidesamong mutants homozygous for different Acc1 alleles suggested that sites onACCase that interact with the different herbicides do not completely overlap.These mutations in maize ACCase should prove useful in characterization of theregulatory role of ACCase in fatty acid biosynthesis and in development ofherbicide-tolerant maize germplasm.
14                                                    NAL Call. No.: SB610.W39Alternatives for control of paraquat tolerant American black nightshade(Solanum americana).Bewick, T.A.; Stall, W.M.; Kostewicz, S.R.; Smith, K.Champaign, Ill. : The Society; 1991 Jan.Weed technology : a journal of the Weed Science Society of America v. 5 (1):p. 61-65; 1991 Jan.  Includes references.
Language:  English
Descriptors: Lycopersicon esculentum; Weed control; Solanum Americanum;Herbicide resistant weeds; Paraquat; Herbicide resistance; Biotypes; Chemicalcontrol; Diquat; Oxyfluorfen; Acifluorfen; Tridiphane; Pyridate; Chelates;Herbicide mixtures; Application rates
15                                                    NAL Call. No.: QH301.A76Alternatives to triazines for weed control in forest nurseries.Mason, W.L.Wellesbourne, Warwick : The Association of Applied Biologists; 1992.Aspects of applied biology (29): p. 149-155; 1992.  In the series analytic:Vegetation management in forestry, amenity and conservation areas. Paperpresented at the conference of the Association, April 7-9, 1992, University ofYork, England.  Includes references.
Language:  English
Descriptors: Great Britain; Forest nurseries; Herbicide resistance;Herbicides; Metazachlor; Site factors; Triazines; Weed control
16                                                     NAL Call. No.: 79.8 W41Amitrole, triazine, substituted urea, and metribuzin resistance in a biotypeof rigid ryegras (Lolium rigidum).Burnet, M.W.M.; Hildebrand, O.B.; Holtum, J.A.M.; Powles, S.B.Champaign, Ill. : Weed Science Society of America; 1991 Jul.Weed science v. 39 (3): p. 317-323; 1991 Jul.  Includes references.
Language:  English
Descriptors: Lolium rigidum; Biotypes; Herbicide resistance; Herbicideresistant weeds; Amitrole; Atrazine; Cross resistance; Simazine; Cyanazine;Propazine; Ametryn; Prometryn; Chlorotoluron; Isoproturon; Metoxuron; Diuron;Fluometuron; Metribuzin; Methazole; Resistance mechanisms; Photosynthesis
Abstract:  A biotype of rigid ryegrass (Lolium rigidum G. LOLRI) has becomeresistant to amitrole and atrazine after 10 yr of exposure to a mixture ofthese herbicides. Resistance has also been demonstrated to thechloro-s-triazines: simazine, cyanazine, propazine; themethylthio-s-triazines: ametryn, prometryn; the substituted ureas:chlortoluron, isoproturon, metoxuron, diuron, fluometuron, methazole; and thetriazinone herbicide metribuzin. The biotype remains susceptible tochlorsulfuron, metsulfuron, sulfometuron, sethoxydim, diclofop, fluazifop,glyphosate, carbetamide, and oxyfluorfen. Inhibition of oxygen evolution byatrazine, diuron, and metribuzin was similar in thylakoids isolated from bothresistant and susceptible biotypes. Therefore, resistance to the photosystemII inhibitors is not caused by an alteration of the target site of theseherbicides. Resistant plants treated with a 3-h pulse of 0.12 millimoleschlortoluron recover photosynthetic activity more rapidly than susceptibleplants. This suggests that the basis for resistance is enhanced metabolism orsequestration of the herbicide within the leaf.
17                                                  NAL Call. No.: QH431.A1G43Analysis of the effects of herbicides on pea seedlings and calluses, and theisolation of herbicide-resistant callus lines and regenerant plants.Ezhova, T.A.; Tikhvinskaya, N.S.; Petrova, T.V.; Bagrova, A.M.; Vasil'ev,I.R.; Matorin, D.N.; Gostimskii, S.A.New York, N.Y. : Consultants Bureau; 1991 May.Soviet genetics v. 26 (11): p. 1317-1322; 1991 May.  Translated from:Genetika, v. 26 (11), 1990, p. 2012-2019. (QH431.A1G4).  Includes references.
Language:  English; Russian
Descriptors: Pisum sativum; Mutants; Induced mutations; In vitro selection;Artificial selection; Seedlings; Callus; Tissue culture; Herbicide resistance;Atrazine; Dinoseb; Glyphosate; Diuron; Inheritance; Heritability
Abstract:  The effects of atrazine, dinoseb, diuron, and glyphosate on peaseedlings and prolonged cultures of photoheterotrophic calluses were compared.Herbicides were found to have similar effects on the growth of seedlings andthe survival of calluses. Cultivation of calluses on selective mediacontaining threshold concentrations of herbicide resulted in the isolation ofcallus lines resistant to the herbicide used (42, 13, 10, and 8 linesresistant to atrazine, dinoseb, diuron, and glyphosate respectively wereobtained). Regenerant plants of the R0 and R1 generations were obtained fromphotosynthesis-blocking herbicide-resistant calluses. Delayed fluorescenceanalysis showed that resistance to photosynthesis-blocking herbicide in thecallus lines selected was not only retained when plants were regenerated, butwas also passed on to the subsequent seed generation (R1), demonstrating itsgenetic nature. Resistance to atrazine in two R1 regenerant lines was shown toresult from reductions in the sensitivity of electron transfer to the acceptorcomponent of photosystem II, which is presumably due to alterations in theherbicide binding protein D-1.
18                                                  NAL Call. No.: SB610.2.B74Annual ryegrass: an abundance of resistance, a plethora of mechanisms.Holtum, J.A.M.; Powles, S.B.Surrey : BCPC Registered Office; 1991.Brighton Crop Protection Conference-Weeds v. 3: p. 1071-1078; 1991.  Meetingheld November 18-21, 1991, Brighton, England.  Includes references.
Language:  English
Descriptors: Australia; Lolium rigidum; Biotypes; Herbicide resistance;Inheritance; Phenoxypropionic herbicides; Chlorsulfuron
19                                                     NAL Call. No.: 381 B522Apparent destabilization of the S1 state related to herbicide resistance in acyanobacterium mutant.Kirilovsky, D.; Ducruet, J.M.; Etienne, A.L.Amsterdam : Elsevier Science Publishers; 1991 Sep27.Biochimica et biophysica acta : International journal of biochemistry andbiophysics v. 1060 (1): p. 37-44; 1991 Sep27.  Includes references.
Language:  English
Descriptors: Metribuzin; Cyanobacteria; Mutants; Photosystem ii; Herbicideresistance
Abstract:  In this work we describe a new phenotype of herbicide-resistantmutants. We have selected and characterized several metribuzin resistantmutants from Synechocystis 6714. We found that an increase in metribuzinresistance involved a cross-resistance with other herbicides. Therefore, themutants could be classified in three groups: (1) metribuzin resistant; (2)atrazine and metribuzin resistant; (3) DCMU, atrazine and metribuzinresistant. Mutants which did not present cross-resistance were up to 25-foldmore resistant to metribuzin than the wild type. We have studied the electrontransfer properties of Photosystem II in these mutants using severaltechniques (oxygen emission, fluorescence, and thermoluminescencemeasurements). They presented modifications in the electron transfer betweenQA and QB, as was generally observed in most herbicide-resistant mutantspreviously studied. However, unexpectedly, one of these mutants, M30,presented a modified oscillatory pattern of oxygen emission. After darkadaptation the maximum of the oscillation was shifted by one flash. The matrixanalysis indicated that the shifted maximum of the oxygen sequencecorresponded to an increased S0 concentration in the dark-adapted state. Inwhole cells S0 and S1 are in equilibrium. This equilibrium is shifted in favorof S0 in the M30 mutant. The mutation renders the S-states more accessible tocell reductants.
20                                                      NAL Call. No.: S77.I56Applications of biotechnology to crop improvement.Warnes, D.D.; Somers, D.A.Morris, Minn. : The Station; 1992.Innovations - University of Minnesota, West Central Experiment Station v. 2(1): p. 5; 1992.
Language:  English
Descriptors: Plant breeding; Genetic engineering; Genetic resistance;Herbicide resistance; Pest resistance
21                                                     NAL Call. No.: 79.8 W41Applications of molecular biology in weed science.Dyer, W.E.Champaign, Ill. : Weed Science Society of America; 1991 Jul.Weed science v. 39 (3): p. 482-488; 1991 Jul.  Paper presented at the"Symposium on New Techniques adn Advances in Weed Physiology and MolecularBiology," February 6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Weeds; Weed biology; Molecular biology; Transgenics; Laboratorymethods; Restriction mapping; Restriction fragment length polymorphism;Cloning; Dna hybridization; Gene transfer; Electrophoresis; Gene expression;Genome analysis; Genetic analysis
Abstract:  Rapid strides are being made in understanding the fundamentalregulation of plant growth, development, and responses to the environment dueto recent advances in molecular biology. Current questions in weed sciencesuch as herbicide mechanisms of action, biodegradation, and mechanisms of weedresistance are equally approachable using such methodology. Efforts tointroduce herbicide resistance into agronomically important crops are possiblebecause of successful isolation and transfer of genes. Investigations of weedsurvival and competitive strategies based on developmental processes, such asseed dormancy, are currently underway using techniques designed to monitor andcharacterize differential gene expression. Molecular methodology also plays akey role in taxonomic studies of weed populations using restriction fragmentlength polymorphism (RFLP) mapping. The future potential for these and othertechniques such as nucleic acid hybridization, polymerase chain reaction(PCR), gene transfer, and the use of transgenic plants is described.
22                                                    NAL Call. No.: SB951.P47An association between triazine resistance and powdery mildew resistance inEpilobium ciliatum and Senecio vulgaris.Clay, D.V.; Nash, C.; Bailey, J.A.Essex : Elsevier Applied Science Publishers; 1991.Pesticide science v. 33 (2): p. 189-196; 1991.  Includes references.
Language:  English
Descriptors: Uk; Epilobium; Senecio vulgaris; Atrazine; Herbicide resistance;Disease resistance; Mildews; Erysiphe cichoracearum; Sphaerotheca;Susceptibility; Relationships; Types
Abstract:  The response of four naturally, occurring biotypes of Epilobiumciliatum and four sources of Senecio vulgaris to the herbicide atrazine werecompared with their susceptibility to the powdery mildews Sphaerothecaepilobii and Erysiphe cichoracearum. Biotypes that were resistant to atrazinewere also resistant to mildew. Mechanisms that night explain the associationbetween atrazine resistance and mildews resistance are discussed, along withpossible implications of these findings for farmland ecology, an for theproduction of herbicide- and mildew-resistant crop plants.
23                                                     NAL Call. No.: 450 P692Atrazine resistance in a velvetleaf (Abutilon theophrasti) biotype due toenhanced glutathione S-transferase activity.Anderson, M.P.; Gronwald, J.W.Rockville, Md. : American Society of Plant Physiologists; 1991 May.Plant physiology v. 96 (1): p. 104-109; 1991 May.  Includes references.
Language:  English
Descriptors: Maryland; Minnesota; Abutilon theophrasti; Biotypes; Atrazine;Herbicide resistance; Glutathione transferase; Enzyme activity; Geneticresistance
Abstract:  We previously reported that a velvetleaf (Abutilon theophrastiMedic) biotype found in Maryland was resistant to atrazine because of anenhanced capacity to detoxify the herbicide via glutathione conjugation (JWGronwald, Andersen RN, Yee C [1989] Pestic Biochem Physiol 34: 149-163). Thebiochemical basis for the enhanced atrazine conjugation capacity in thisbiotype was examined. Glutathione levels and glutathione S-transferaseactivity were determined in extracts from the atrazine-resistant biotype andan atrazine-susceptible or "wild-type" velvetleaf biotype. In both biotypes,the highest concentration of glutathione (approximately 600 nanomoles per gramfresh weight) was found in leaf tissue. However, no significant differenceswere found in glutathione levels in roots, stems, or leaves of either biotype.In both biotypes, the highest concentration of glutathione S-transferaseactivity measured with 1-chloro-2,4-dinitrobenzene or atrazine as substratewas in leaf tissue. Glutathione S-transferase measured with1-chloro-2,4-dinitrobenzene as substrate was 40 and 25% greater in leaf andstem tissue, respectively, of the susceptible biotype compared to theresistant biotype. In contrast, glutathione S-transferase activity measuredwith atrazine as substrate was 4.4- and 3.6-fold greater in leaf and stemtissue, respectively, of the resistant biotype. Kinetic analyses ofglutathione S-transferase activity in leaf extracts from the resistant andsusceptible biotypes were performed with the substrates glutathione,1-chloro-2,4-dinitrobenzene, and atrazine. There was little or no change inapparent Km values for glutathione, atrazine, or 1-chloro-2,4-dinitrobenzene.However, the Vmax for glutathione and atrazine were approximately 3-foldhigher in the resistant biotype than in the susceptible biotype. In contrast,the Vmax for 1-chloro-2,4-dinitrobenzene was 30% lower in the resistantbiotype. Leaf glutathione S-transferase isozymes that exhibit activity withatrazine and 1-chloro-2,4-dinitrobenzene were separated by fast protein liquid(anion-exchange) chromatography.  The susceptible biotype, had three peaksexhibiting activity with atrazine and the resistant biotype had two.  The twopeaks of glutathione S-transferase activity with atrazine from the resistantbiotype coeluted with two of the peaks from the susceptible biotype, but peakheight was three- to fourfold greater in the resistant biotype, in bothbiotypes, two of the peaks that exhibit glutathione S-transferase activitywith atrazine also exhibited activity with 1-chloro-2,4-dinitrobenzene, withthe peak height being greater in the susceptibele biotype.  The resulstsindicated that atraine glutathionse S-trasferase activity for atrazineresistant in the velvetleaf biotype from Maryland is due to enhancedglutathione S-transferase activity foratrazine in leaf and stem tissue whichresults in an enhanced capacity to detoxify the herbicide via glutathioneconjugation.
24                                                    NAL Call. No.: 79.8 W412Attempts to transfer paraquat resistance from barley grass (Hordeum glaucumSteud.) to barley and wheat.Islam, A.K.M.R.; Australia; Powles, S.B.Oxford : Blackwell Scientific Publications; 1991 Dec.Weed research v. 31 (6): p. 395-399; 1991 Dec.  Includes references.
Language:  English
Descriptors: Hordeum vulgare; Triticum aestivum; Selection criteria; Herbicideresistance; Paraquat; Hybridization; Hordeum glaucum; Transfer
25                                                    NAL Call. No.: QP601.M49The bar gene as selectable and screenable marker in plant engineering.D'Halluin, K.; Block, M. de; Denecke, J.; Janssens, J.; Leemans, J.;Reynaerts, A.; Botterman, J.San Diego, Calif. : Academic Press; 1992.Methods in enzymology (216): p. 397-414; 1992.  In the series analytic:Recombinant DNA (part G) / edited by R. Wu.  Includes references.
Language:  English
Descriptors: Plants; Bilanafos; Herbicide resistance; Reporter genes; Markergenes; Genetic transformation; Plant breeding; Molecular biology; Tissuecultures
26                                                     NAL Call. No.: 79.8 W41Basis of differential tolerance of two corn hybrids (Zea mays) to metolachlor.Cottingham, C.K.; Hatzios, K.K.Champaign, Ill. : Weed Science Society of America; 1992 Jul.Weed science v. 40 (3): p. 359-363; 1992 Jul.  Includes references.
Language:  English
Descriptors: Zea mays; Hybrids; Herbicide resistance; Metolachlor; Varietalsusceptibility; Enzyme activity; Glutathione transferase; Metabolicdetoxification; Absorption; Translocation; Pharmacokinetics; Phytotoxicity;Crop damage
Abstract:  Greenhouse and laboratory studies were conducted to determine thebasis of differential response of two corn hybrids to the chloroacetanilideherbicide metolachlor. In greenhouse experiments, metolachlor at 6.7 kg ha-1reduced the height of the susceptible 'Northrup-King 9283' corn by 53%relative to untreated controls and caused extensive visible injury 14 d aftertreatment. Under the same conditions, the height of metolachlor-treated'Cargill 7567' corn seedlings was reduced by only 18% without any visibleherbicide injury. The 14C-metolachlor was more rapidly absorbed by theemerging shoot of the metolachlor-susceptible hybrid, Northrup-King 9283.Thus, differential metolachlor tolerance may be due in part to processes atthe level of herbicide uptake. Metabolism experiments revealed that bothhybrids were able to conjugate 14C-metolachlor with glutathione at similarrates. However, glutathione S-transferase activity increased earlier duringseedling development and reached higher activities in the metolachlor-toleranthybrid, Cargill 7567.
27                                                     NAL Call. No.: QH442.B5Bialaphos treatment of transgenic rice plants expressing a bar gene preventsinfection by the sheath blight pathogen (Rhizoctonia solani).Uchimiya, H.; Iwata, M.; Nojirl, C.; Samarajeewa, P.K.; Takamatsu, S.; Ooba,S.; Anzai, H.; Christensen, A.H.; Quail, P.H.; Toki, S.New York, N.Y. : Nature Publishing,; 1993 Jul.Bio/technology v. 11 (7): p. 835-836; 1993 Jul.  Includes references.
Language:  English
Descriptors: Oryza sativa; Rhizoctonia solani; Transgenic plants; Genetictransformation; Disease resistance; Glyphosate; Herbicide resistance; Blight;Structural genes; Acyltransferases
28                                                  NAL Call. No.: QD415.A1B58Biochemcial characterization of tobacco mutants resistant to azole fungicidesand herbicides.Schaller, H.; Maillot-Vernier, P.; Gondet, L.; Belliard, G.; Benveniste, P.London : Portland Press; 1993 Nov.Transactions v. 21 (4): p. 1052-1057; 1993 Nov.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Mutants; Conazole fungicides; Imidazolinoneherbicides; Fungicide tolerance; Herbicide resistance
29                                                  NAL Call. No.: SB950.9.C44Biochemical basis of herbicide resistance.Vaughn, K.C.; Duke, S.O.Berlin, W. Ger. : Springer-Verlag; 1991.Chemistry of plant protection v. 7: p. 141-169; 1991.  In the series analytic:Herbicide resistance--brassinosteroids, gibberellins, plant growth regulators/ edited by W. Ebing.  Literature review.  Includes references.
Language:  English
Descriptors: Herbicide resistant weeds; Biotypes; Herbicide resistance;Resistance mechanisms; Glyphosate; Sulfonylurea herbicides; Imidazolinoneherbicides; Glufosinate; Triazine herbicides; Paraquat; Dinitroanilineherbicides; Mcpa; 2,4-d; Mode of action; Biochemical pathways; Enzymeinhibitors; Biosynthesis; Amino acids; Photosynthesis; Mitosis; Cell walls;Literature reviews
30                                              NAL Call. No.: SB957.R474 1991Biochemical mechanisms of resistance to photosystem II herbicides.Rensen, J.J.S. van; Vos, O.J. deLondon : Published for SCI by Elsevier Applied Science; 1991.Resistance '91, Achievement and Developments in Combating Pesticide Resistance/ edited by Ian Denholm, Alan L. Devonshire, and Derek W. Hollomon. p.251-261; 1991.  Proceedings of the SCI Symposium "Resistance '91: Achievementsand Developments in Combating Pesticide Resistance," 15-17 July 1991,Rothamsted Experimental Station, Harpenden, UK.  Includes references.
Language:  English
Descriptors: Photosystem ii; Herbicide resistance; Photoinhibition
31                                                  NAL Call. No.: QH442.G4522Biotech fix for African crops held hostage to profit motive.Conroy, D.Washington, D.C. : King Pub. Group; 1993 Feb17.Biotech daily v. 2 (124): p. 3; 1993 Feb17.
Language:  English
Descriptors: Africa; Herbicide resistance; Genetic engineering; Food crops;Food supply
32                                                     NAL Call. No.: QH442.B5Biotechnology in the food industry.Beck, C.I.; Ulrich, T.New York, N.Y. : Nature Publishing Company; 1993 Aug.Bio/technology v. 11 (8): p. 895-902; 1993 Aug.  Includes references.
Language:  English
Descriptors: Food crops; Plant breeding; Genetic engineering; Biotechnology;Food quality; Food processing quality; Genetic resistance; Herbicideresistance; Plant development
33                                                     NAL Call. No.: 79.8 W41A biotype of hare barley (Hordeum leporinum) resistant to paraquat and diquat.Tucker, E.S.; Powles, S.B.Champaign, Ill. : Weed Science Society of America; 1991 Apr.Weed science v. 39 (2): p. 159-162; 1991 Apr.  Includes references.
Language:  English
Descriptors: Victoria; Hordeum murinum subsp. leporinum; Biotypes; Herbicideresistance; Paraquat; Diquat; Sethoxydim; Fluazifop; Glyphosate; Crossresistance; Dry matter accumulation; Growth rate; Survival; Weed biology
Abstract:  A biotype of the annual grass weed hare barley infesting an alfalfafield with a 24-yr history of the use of the bipyridylium herbicides paraquatand diquat, was investigated for resistance to these herbicides. Rates of upto 800 g ai ha-1 of each herbicide caused no mortality in the hare barleyplants from this field. The same species, collected from an adjacent pasturefield with no history of bipyridylium herbicide application, exhibited LD50'sof 57 and 160 g ai ha-1 for paraquat and diquat, respectively. Tiller numbersand dry matter production in the biotype from the alfalfa field were notaffected by the normal rate recommended for both herbicides. These resultsclearly show that hare barley from the alfalfa field is resistant to paraquatand diquat. Both biotypes were equally sensitive to fluazifop, glyphosate, andsethoxydim.
34                                                       NAL Call. No.: A00035Breakthrough should lead to higher wheat yields.Summit, N.J. : CTB International Pub. Co; 1992 Jun04.Biotechnology news v. 12 (14): p. 1-2; 1992 Jun04.
Language:  English
Descriptors: Triticum aestivum; Genetic engineering; Micromanipulation;Herbicide resistance
35                                                       NAL Call. No.: SB1.H6Buffalograss tolerance to postemergence herbicides.McCarty, L.B.; Colvin, D.L.Alexandria, Va. : American Society for Horticultural Science; 1992 Aug.HortScience v. 27 (8): p. 898-899; 1992 Aug.  Includes references.
Language:  English
Descriptors: Buchloe dactyloides; Lawns and turf; Weed control; Chemicalcontrol; 2,4-d; Dicamba; Bentazone; Mecoprop; Metsulfuron; Quinclorac;Imazaquin; Diclofop; Triclopyr; Atrazine; Asulam; Sethoxydim; Msma;Sulfometuron; Herbicide resistance
Abstract:  Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] is a turfgrassspecies traditionally adapted to low-rainfall areas that may incurunacceptable weed encroachment when grown in higher rainfall areas such asFlorida. An experiment was performed to evaluate the tolerance of two newbuffalograss cultivars, 'Oasis' and 'Prairie', to postemergence herbicidescommonly used for grass, broadleaf, and sedge weed control. Twenty to 40 dayswere required for each cultivar to recover from treatment with asulam, MSMA,and sethoxydim (2.24, 2.24, and 0.56 kg.ha-1, respectively). Other herbicidesused for postemergence grass weed control (metsulfuron, quinclorac, anddiclofop at 0.017, 0.56, and 1.12 kg.ha-1, respectively) did not causeunacceptable buffalograss injury. Herbicides used for postemergence broadleafweed control, triclopyr, 2,4-D, sulfometuron, dicamba (0.56, 1.12, 0.017, and0.56 kg.ha-1, respectively), and a three-way combination of 2,4-D + dicamba +mecoprop (1.2 + 0.54 + 0.13 kg.ha-1), caused 20 to 30 days of unacceptable ormarginally acceptable turfgrass quality, while 20 days were required for'Prairie' buffalograss to recover from atrazine treatments. 'Oasis'buffalograss did not fully recover from 2,4-D or 2,4-D + dicamba + mecopropthrough 40 days after treatment. Herbicides used for postemergence sedgecontrol, bentazon and imazaquin, caused slightly reduced, but acceptable,levels of turf quality in both cultivars throughout the experiment.
36                                         NAL Call. No.: TP248.27.P55P53 1991Cell selection.Loh, W.H.T.Oxford : Pergamon Press; 1992.Plant biotechnology : comprehensive biotechnology, second supplement / volumeeditors, Michael W. Fowler & Graham S. Warren; editor-in-chief, MurrayMoo-Young. p. 33-44; 1992.  Literature review.  Includes references.
Language:  English
Descriptors: Plants; Mutants; Induced mutations; In vitro selection; Herbicideresistance; Salt tolerance; Metal tolerance; Heavy metals; Disease resistance;Tissue culture; Cell culture; Literature reviews
37                                                   NAL Call. No.: SB123.P535Characterization of a spontaneous rapeseed mutant tolerant to sulfonylurea andimidazolinone herbicides.Magha, M.I.; Guerche, P.; Bregeon, M.; Renard, M.Berlin : P. Parey, 1986-; 1993 Sep.Plant breeding; Zeitschrift fur Pflanzenzuchtung v. 111 (2): p. 132-141; 1993Sep.  Includes references.
Language:  English
Descriptors: Brassica napus; Mutants; Mutations; Structural genes;Oxo-acid-lyases; Dominance; Herbicide resistance; Chlorsulfuron; Triasulfuron;Metsulfuron; Imazamethabenz
38                                                     NAL Call. No.: 79.8 W41Characterization of acifluorfen tolerance in selected somaclones of easternblack nightshade (Solanum ptycanthum).Yu, C.Y.; Masiunas, J.B.Champaign, Ill. : Weed Science Society of America; 1992 Jul.Weed science v. 40 (3): p. 408-412; 1992 Jul.  Includes references.
Language:  English
Descriptors: Solanum; Herbicide resistant weeds; Acifluorfen; Somaclonalvariation; Herbicide resistance; Absorption; Translocation; Metabolism;Metabolic detoxification; Cross resistance; Diquat; Oxyfluorfen; Paraquat
Abstract:  Acifluorfen tolerance in eastern black nightshade somaclones wascharacterized in two experiments. One experiment determined the involvement ofabsorption, translocation, and metabolism in acfiluorfen tolerance. Less than6% of the applied 14C-acifluorfen was absorbed. There were no differences inacifluorfen absorption between susceptible and tolerant somaclones. More14C-acifluorfen was translocated in the susceptible than the tolerantsomaclones. The susceptible somaclone did not metabolize acifluorfen whilesome somaclones (i.e., EBN-3A) metabolized 14C-acifluorfen. A secondexperiment determined the tolerance of the somaclones to oxyfluorfen, diquat,and paraquat. Most acifluorfen-tolerant somaclones were tolerant tooxyfluorfen but were susceptible to diquat and paraquat. One somaclone,EBN-3A, was extremely tolerant to acifluorfen, paraquat, and diquat.
39                                                    NAL Call. No.: SB957.R47Characterization of resistance to atrazine in a velvetleaf (Abutilontheophrasti Medik.) biotype from Wisconsin.Gray, J.A.; Stoltenberg, D.E.; Balke, N.E.East Lansing, Mich. : Pesticide Research Center, Michigan State University,;1993.Resistant pest management v. 5 (2): p. 17; 1993.
Language:  English
Descriptors: Wisconsin; Cabt; Abutilon theophrasti; Herbicide resistant weeds;Biotypes; Atrazine; Herbicide resistance
40                                                     NAL Call. No.: 442.8 Z8Characterization of transgenic sulfonylurea-resistant flax (Linumusitatissimum).McSheffrey, S.A.; McHughen, A.; Devine, M.D.Berlin, W. Ger. : Springer International; 1992.Theoretical and applied genetics v. 84 (3/4): p. 480-481; 1992.  Includesreferences.
Language:  English
Descriptors: Linum usitatissimum; Arabidopsis thaliana; Agrobacteriumtumefaciens; Genetic transformation; Transgenics; Gene transfer; Ligases;Structural genes; Enzyme activity; Herbicide resistance; Chlorsulfuron;Metsulfuron; Segregation; Inheritance; Line differences; Roots; Growth
Abstract:  Fourteen transgenic flax (Linum usitatissimum) lines, carrying amutant Arabidopsis acetolactate synthase (ALS) gene selected for resistance tochlorsulfuron, were characterized for resistance to two sulfonylureaherbicides. Progeny of 10 of the 14 lines segregated in a ratio of 3 resistantto 1 susceptible, indicating a single insertion. Progeny of 1 line segregatedin a 15:1 ratio, indicating two insertions of the ALS gene at independentloci. Progeny from 3 lines did not segregate in a Mendelian fashion and werelikely the products of chimeric shoots. Resistance to chlorsulfuron was stablyinherited in all lines. At the enzyme level, the transgenic lines were 2.5 tomore than 60 times more resistant to chlorsulfuron than the parental lines.The transgenic lines were 25-260 times more resistant to chlorsulfuron thanthe parental lines in root growth experiments and demonstrated resistance whengrown in soil treated with 20 g ha-1 chlorsulfuron. The lines demonstratedless resistance to metsulfuron methyl; in root growth experiments, thetransgenic lines were only 1.6-4.8 times more resistant to metsulfuron methylthan the parental lines. Resistance was demonstrated in the field at half(2.25 g ha-1) and full (4.5 g ha-1) rates of metsulfuron methyl.
41                                                    NAL Call. No.: SB951.P49Chlorsulfuron inhibition of phloem translocation in chlorsulfuron-resistantand -susceptible Arabidopsis thaliana.Hall, L.M.; Devine, M.D.Orlando, Fla. : Academic Press; 1993 Feb.Pesticide biochemistry and physiology v. 45 (2): p. 81-90; 1993 Feb.  Includesreferences.
Language:  English
Descriptors: Chlorsulfuron; Phloem loading; Inhibition; Arabidopsis thaliana;Types; Herbicide resistance; Susceptibility; Uptake mechanisms; Sucrose;Plasma membranes; Microsomes; Enzymes; Adenosinetriphosphatase; Enzymeactivity; Protein content
Abstract:  The herbicide chlorsulfuron is not translocated readily in plantsbecause of an inhibitory effect on phloem translocation. More chlorsulfuronwas translocated in a chlorsulfuron-resistant (R) biotype of Arabidopsisthaliana than in a susceptible (S) biotype, indicating that the effect ontranslocation is secondary to inhibition of ALS, the primary site of action ofthe herbicide. The R biotype did not different from the S biotype in itsability, to translocate exogenously applied sucrose: however, translocation ofexogenously applied sucrose following chlorsulfuron treatment was greater inthe R biotype than in the S biotype. Chlorsulfuron pretreatment inhibitedrapid sucrose uptake into leaf discs by 41% in the S biotype but by only 17%in the R biotype. This result suggests that chlorsulfuron inhibits phloemtransport by restricting sucrose uptake into the phloem. Purified plasmamembrane preparations extracted from the two biotypes following chlorsulfurontreatment did not differ in H+ -ATPase activity or total plasmalemma proteincontent. Possible alternative mechanisms by which chlorsulfuron may inhibitphloem transport are discussed.
42                                                     NAL Call. No.: 79.8 W41Chlorsulfuron-resistant sugarbeet: cross-resistance and physiological basis ofresistance.Hart, S.E.; Saunders, J.W.; Penner, D.Champaign, Ill. : Weed Science Society of America; 1992 Jul.Weed science v. 40 (3): p. 378-383; 1992 Jul.  Includes references.
Language:  English
Descriptors: Beta vulgaris; Herbicide resistance; Chlorsulfuron; Crossresistance; Chlorimuron; Imidazolinone herbicides; Sulfonylurea herbicides;Enzyme inhibitors; Oxo-acid-lyases; Enzyme activity; Absorption; Metabolism
Abstract:  Greenhouse and laboratory studies were conducted to determine theextent of cross-resistance of chlorsulfuron-resistant sugarbeet (CR1-B) toother herbicides that inhibit acetolactate synthase (ALS) and to determine thephysiological basis of resistance. Cross-resistance to metsulfuron, imazaquin,and imazethapyr was not evident, while only marginal cross-resistance wasobserved to triasulfuron, DPX-L5300, and nicosulfuron. CR1-B was moderatelyresistant to chlorsulfuron and chlorimuron and was highly cross-resistant tothifensulfuron and primisulfuron. Further greenhouse studies demonstrated thatCR1-B was not significantly injured by thifensulfuron and primisulfuronapplied at or exceeding the field use rate. Studies with 14C-primisulfuronshowed that differential absorption or metabolism of primisulfuron could notaccount for the observed resistance. ALS enzyme assays showed that the CR1-BALS enzyme activity was 66, 26, and 13 times less sensitive to chlorsulfuron,thifensulfuron, and primisulfuron inhibition, respectively, compared to ALSenzyme extracted from sensitive sugarbeets. An altered ALS enzyme, which isless sensitive to sulfonylurea herbicide inhibition, appears to be thephysiological basis of resistance.
43                                                    NAL Call. No.: SD112.F67Clonal variation in tolerance to hexazinone.Borough, C.; Jamieson, D.Rotorua : The Institute; 1991.FRI bulletin - Forest Research Institute, New Zealand Forest Service (160): p.139-141; 1991.  Paper presented at the "FRI/NZFP Forest Ltd., Clonal ForestryWorkshop, May 1-2, 1989, Rotorua, New Zealand.
Language:  English
Descriptors: Forest trees; Clones; Hexazinone; Herbicide resistance; Geneticvariation
44                                                 NAL Call. No.: TP248.13.S68Cloning and expression of mutant EPSP-synthetase gene of Escherichia coli intransgenic plants.Mett, V.L.; Urmeeva, F.I.; Kobets, N.S.; Kolganova, T.V.; Aliev, K.A.;Piruzyan, E.S.New York, N.Y. : Allerton Press; 1991.Soviet biotechnology (3): p. 27-33; 1991.  Translated from: Biotekhnologiia,(3), 1991, p. 19-22, (TP248.2.B57).  Includes references.
Language:  English; Russian
Descriptors: Genetic engineering; Escherichia coli; Mutants; Glyphosate;Herbicide resistance; Treatment; Nitroso compounds; Guanidines; Geneticanalysis; Phosphates; Ligases; Genetic code; Gene expression; Cloning;Plasmids; Transgenics; Nicotiana tabacum
45                                                     NAL Call. No.: 79.8 W41Cole crop (Brassica oleracea) tolerance to clomazone.Scott, J.E.; Weston, L.A.Champaign, Ill. : Weed Science Society of America; 1992 Jan.Weed science v. 40 (1): p. 7-11; 1992 Jan.  Includes references.
Language:  English
Descriptors: Brassica oleracea; Herbicide resistance; Clomazone; Bioassays;Chlorophyll; Biosynthesis; Application rates; Metabolic inhibitors; Mode ofaction; Metabolic detoxification; Source sink relations; Metabolites; Roots;Uptake; Translocation
Abstract:  A laboratory bioassay was conducted to determine the differentialtolerance of cole crops to clomazone as measured by extractable totalchlorophyll and carotenoids. Clomazone concentrations causing 50% inhibition(I50) in the biosynthesis of total chlorophyll in broccoli, cauliflower, andgreen and red cabbage cotyledons were 16, 11, 3, and 11 micromolarrespectively, while I50 values for carotenoid levels were 20, 10, 4, and 8micromolar clomazone, respectively. Therefore, broccoli was the most tolerantto clomazone based upon extractable chlorophyll and carotenoid concentrations.Further laboratory studies were performed to investigate the basis fordifferential clomazone tolerance in 3-wk-old cole crop seedlings. Nodifferences in total root uptake of 14C-clomazone were observed between thesecrops after 24 h. There were no differences in rate of metabolism of14C-clomazone to methanol-soluble metabolites in roots of these crops.Percentage of polar metabolites in roots remained fairly constant over time.There were also no differences between crops in percentage of methanol-soluble14C-clomazone metabolites formed in shoots between 24 and 96 h. In all crops,levels of 14C-clomazone decreased in a similar manner over time in methanolicextracts of roots and shoots while nonextractable 14C levels increased,indicating a conversion of clomazone to insoluble, nonextractable forms.Differential uptake, translocation, and metabolism do not appear to accountfor clomazone selectivity differences between cole crop seedlings.
46                                                    NAL Call. No.: SB951.P49Comparative uptake, translocation, and metabolism of paraquat in tolerantKwangkyo and susceptible Hood soybean.Kim, S.; Hatzios, K.K.Orlando, Fla. : Academic Press; 1993 Oct.Pesticide biochemistry and physiology v. 47 (2): p. 149-158; 1993 Oct.Includes references.
Language:  English
Descriptors: Glycine max; Cultivars; Susceptibility; Herbicide resistance;Paraquat; Uptake; Deposition; Leaves; Waxes; Absorption; Spatial distribution;Plant tissues; Translocation; Metabolism; Mode of action
Abstract:  The "Kwangkyo" and "Hood" cultivars of soybean [Glycine max (L.)Merr.] are differentially sensitive to the herbicide paraquat. The margin ofthis intraspecific differential herbicide tolerance is narrow and Kwangkyo isabout 10-fold more tolerant to paraquat than Hood soybean. The deposition ofepicuticular wax on the surface of the first fully expanded trifoliolate wassimilar in both soybean cultivars and treatment with 1 millimole paraquat didnot influence the epicuticular wax content in any cultivar. Seedlings ofKwangkyo and Hood soybean absorbed comparable amounts of radioactivityfollowing exposure to root-applied 14C-labeled paraquat for 24 hr. Most of theabsorbed radioactivity remained in the roots of seedlings of both cultivars,but a greater amount of the recovered radioactivity translocated from roots tostems and leaves of the sensitive Hood soybean. Following feeding of the cutends of their petioles with [14C]paraquat for 12 and 24 hr, excisedtrifoliolates of Kwangkyo soybean retained a greater portion of absorbedradioactivity in their petioles and translocated a smaller amount ofradioactivity into the interveinal regions. By contrast, excised trifoliolatesof Hood soybean retained a smaller portion of absorbed radioactivity in theirpetioles and released a higher amount of absorbed radioactivity into theinterveinal regions. Extractable paraquat was not metabolized to any extent bytissues of either of the two cultivars and differential metabolism does notappear to play a role in the observed differential response of Kwangkyo andHood soybean to paraquat. Overall, the results of the present study suggestthat restricted mobility or a delayed release of paraquat into the mesophyllregion is a likely basis for the observed tolerance of Kwangkyo soybean to theherbicide paraquat.
47                                                    NAL Call. No.: SB610.W39Concerns a weed scientist might have about herbicide-tolerant crops.Radosevich, S.R.; Ghersa, C.M.; Comstock, G.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 635-639; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Herbicide resistance; Weed control;Biotechnology; Ethics
48                                                    NAL Call. No.: SB610.W39Concerns of seed company officials with herbicide-tolerant cultivars.Duvick, D.N.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 640-646; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Seed industry; Transgenic plants; Herbicide resistance;Cultivars; Biotechnology; Profitability; Supply balance; Research
49                                                     NAL Call. No.: QR53.B56Construction of multiple herbicide resistant ammonia excreting strains ofcyanobacterium Nostoc muscorum.Modi, D.R.; Singh, D.R.; Rao, A.K.; Chakravarty, K.S.; Singh, H.N.Middlesex : Science and Technology Letters; 1991 Nov.Biotechnology letters v. 13 (11): p. 793-798; 1991 Nov.  Includes references.
Language:  English
Descriptors: Nostoc muscorum; Strains; Gloeocapsa; Herbicides; Herbicideresistance; Phenotypes; Dna; Genetic transformation; Gene transfer; Mutations;Ammonia; Excretion; Photosystem ii; Nitrogen fixation
Abstract:  Machete resistant (Matr), basalin resistant (Basr), 3(3,4dichlorophenyl)-1,1-dimethyl urea resistant (DCMUr), atrazine resistant(Atr(r)) and propanil resistant (Prpr) phenotypes Gloeocapsa sp. werecontransformed to Nostoc muscorum at high frequency. Spontaneously occurringmutants of the multiple herbicide resistant transformant containingL-methionine-DL-sulfoximine resistant (Msxr), ethylene diamine resistant(Edar) of phosphinothricin resistant (Pptr) glutamine synthetase (GS) showedextracellular liberation of ammonia resulting from fixation of N2 underphotosynthetic conditions. Results suggest a definite role of GS activity inregulation of extracellular ammonia.
50                                                    NAL Call. No.: SB610.W39Control of annual bluegrass (Poa annua) in Kentucky bluegrass (Poa pratensis)turf with linuron.Hall, J.C.; Carey, C.K.Champaign, Ill. : The Weed Science Society of America; 1992 Oct.Weed technology : a journal of the Weed Science Society of America v. 6 (4):p. 852-857; 1992 Oct.  Includes references.
Language:  English
Descriptors: Ontario; Cabt; Poa pratensis; Cultivars; Herbicide resistance;Linuron; Application rates; Poa annua; Weed control; Chemical control; Plantdensity; Quality; Seedling emergence; Injuries; Temperate climate
51                                                    NAL Call. No.: 79.9 W52RControl of diclofop-resistant Italian ryegrass.Brewster, B.D.; Donaldson, W.S.; Appleby, A.P.S.l. : The Society; 1992.Research progress report - Western Society of Weed Science. p. III/128; 1992.Meeting held on March 9-12, 1992, Salt Lake City, Utah.
Language:  English
Descriptors: Oregon; Lolium multiflorum; Diclofop; Herbicide resistance; Weedcontrol
52                                                     NAL Call. No.: SB476.G7Controlling weeds in ornamental grasses.Whitwell, T.Overland Park, Kan. : Intertec Publishing Corporation; 1993 Aug.Grounds maintenance v. 28 (8): p. 26-30; 1993 Aug.
Language:  English
Descriptors: Grasses; Ornamental herbaceous plants; Weed control; Herbicides;Herbicide resistance
53                                                    NAL Call. No.: SB951.P49Correlation of propanil hydrolyzing enzyme activity with leaf morphology inwild rices of genome CCDD.Jun, C.J.; Matsunaka, S.Orlando, Fla. : Academic Press; 1991 May.Pesticide biochemistry and physiology v. 40 (1): p. 80-85; 1991 May.  Includesreferences.
Language:  English
Descriptors: Oryza; Wild plants; Hybrids; Leaves; Plant morphology; Amidase;Enzyme activity; Herbicide resistance; Propanil; Phytotoxicity
Abstract:  The propanil hydrolyzing enzyme, aryl acylamidase I (AAI)(arylacylamine amidohydrolase, EC 3.5.1.13), was highly correlated (r = -0.83)with leaf width in three species of genus Oryza with genome CCDD. The specificactivity of AAI was lower in the leaves of wide-leafed plants and this waswell-reflected in propanil phytotoxicity in those plants. There were nosignificant differences between conjugation of 3,4-dichloroaniline or thepresence of AAI inhibitors in the crude enzyme solutions from thenarrow-leafed and wide-leafed strains. The same relationship between AAIactivity and leaf width was observed in interspecific F, hybrids involvinggenome CCDD. In those F1 hybrids the wide- and narrow-leafed strains showedcomparable AAI activity per leaf of equal length. It was concluded that theconcentration of the enzyme in the CCDD plants was diluted by plant bulk inthe wide-leafed strains and the correlation appeared to be the indirect effectof genes altering plant morphology, especially leaf area. The significance ofthe correlations is discussed in relation to propanil resistance and plantphylogenetics.
54                                                     NAL Call. No.: 442.8 Z8The cost of herbicide resistance measured by a competition experiment.Reboud, X.; Till-Bottraud, I.Berlin, W. Ger. : Springer International; 1991.Theoretical and applied genetics v. 82 (6): p. 690-696; 1991.  Includesreferences.
Language:  English
Descriptors: Setaria italica; Herbicide resistance; Atrazine; Plantcompetition; Shoots; Dry matter; Plant height; Seed set; Seeds; Linedifferences; Plant density
Abstract:  The cost of resistance has been measured by a competitionexperiment over a ranee of densities, in the absence of herbicide treatment,on two nearly isogenic lines of Foxtail millet, differing in a chloroplasticresistance to herbicide. Three characters have been measured: shoot height,shoot weight, and seed production. Sensitive individuals were bettercompetitors despite a larger decrease in production under within-biotypecompetition. The cost of resistance was density dependent and increased withdensity. The cost was higher when measured on seed production and reached 65%at the higher density for resistant individuals. This is compatible with thelow frequency or the absence of that gene in natural populations. This workillustrates that the cost is easiest to observe when high levels ofconstraints are used.
55                                                  NAL Call. No.: SB113.2.S45Cotton meets the biotech challenge: genetic engineering races to themarketplace.Cutler, K.Cedar Falls, IA : Freiberg Pub. Co; 1991 Nov.Seed industry v. 42 (10): p. 4-5, 19; 1991 Nov.
Language:  English
Descriptors: Gossypium; Bromoxynil; Herbicide resistance; Genetic engineering;Field tests; Sulfonylurea herbicides; Usda
56                                                     NAL Call. No.: 450 P692Cross-resistance to herbicides in annual ryegrass (Lolium rigidum). II.Chlorsulfuron resistance involves a wheat-like detoxification system.Christopher, J.T.; Powles, S.B.; Liljegren, D.R.; Holtum, J.A.M.Rockville, Md. : American Society of Plant Physiologists; 1991 Apr.Plant physiology v. 95 (4): p. 1036-1043; 1991 Apr.  Includes references.
Language:  English
Descriptors: Lolium rigidum; Triticum aestivum; Biotypes; Chlorsulfuron;Herbicide resistance; Cross resistance; Metabolism; Ligases; Translocation;Phytotoxicity; Metabolic detoxification; Biochemical pathways
Abstract:  Lolium rigidum Gaud. biotype SLR31 is resistant to the herbicidediclofop-methyl and cross-resistant to several sulfonylurea herbicides. Wheatand the cross-resistant ryegrass exhibit similar patterns of resistance tosulfonylurea herbicides, suggesting that the mechanism of resistance may besimilar. Cross-resistant ryegrass is also resistant to the wheat-selectiveimidazolinone herbicide imazamethabenz. The cross-resistant biotype SLR31metabolized [phenyl-U-14C]chlorsulfuron at a faster rate than a biotype whichis susceptible to both diclolop-methyl and chlorsulfuron. A third biotypewhich is resistant to diclofop-methyl but not to chlorsulfuron metabolizedchlorsulfuron at the same rate as the susceptible biotype. The increasedmetabolism of chlorsulfuron observed in the cross-resistant biotype is,therefore, correlated with the patterns of resistance observed in these L.rigidum biotypes. During high performance liquid chromatography analysis themajor metabolite of chlorsulfuron in both susceptible and cross-resistantryegrass coeluted with the major metabolite produced in wheat. The majorproduct is clearly different from the major product in the tolerant dicotspecies, flax (Linium usitatissimum). The elution pattern of metabolites ofchlorsulfuron was the same for both the susceptible and cross-resistantryegrass but the cross-resistant ryegrass metabolized chlorsulfuron morerapidly. The investigation of the dose response to sulfonylurea herbicides atthe whole plant level and the study of the metabolism of chlorsulfuron providetwo independent sets of data which both suggest that the resistance tochlorsulfuron in cross-resistant ryegrass biotype SLR31 involves a wheat-likedetoxification system.
57                                                     NAL Call. No.: 450 P692Cross-resistance to herbicides in annual ryegrass (Lolium rigidum). III. Onthe mechanism of resistance to diclofop-methyl.Holtum, J.A.M.; Matthews, J.M.; Hausler, R.E.; Lijegren, D.R.; Powles, S.B.Rockville, Md. : American Society of Plant Physiologists; 1991 Nov.Plant physiology v. 97 (3): p. 1026-1034; 1991 Nov.  Includes references.
Language:  English
Descriptors: Australia; Lolium rigidum; Leaves; Diclofop; Herbicide resistantweeds; Biotypes; Metabolism; Uptake; Translocation; Genetic variation; Weedcontrol; Weed biology
Abstract:  Annual ryegrass (Lolium rigidum) biotype SLR 31 is resistant to thepostemergent graminicide methyl-2-[4-(2,4-dichlorophenoxy) phenoxy]-propanoate(diclofop-methyl). Uptake of [14C](Uphenyl)diclofop-methyl and root/shootdistribution of radioactivity in susceptible and resistant plants weresimilar. In both biotypes, diclofop-methyl was rapidly demethylated to thebiocidal metabolite diclofop acid which, in turn, was metabolized to ester andaryl-O-sugar conjugates. Susceptible plants accumulated 5 to 15% moreradioactivity in diclofop acid than did resistant plants. Resistant plants hada slightly greater capacity to form nonbiocidal sugar conjugates. Despitethese differences, resistant plants retained 20% of 14C in the biocidalmetabolite diclofop acid 192 hours after treatment, whereas susceptibleplants, which were close to death, retained 30% in diclofop acid. The smalldifferences in the pool sizes of the active and inactive metabolites are bythemselves unlikely to account for a 30-fold difference in sensitivity to theherbicide at the whole plant level. Similar highpressure liquid chromatographyelution patterns of conjugates from both susceptible and resistant biotypesindicated that the mechanisms and the products of catabolism in the biotypesare similar. It is suggested that metabolism of diclofop-methyl by theresistant biotype does not alone explain resistance observed at thewhole-plant level. Diclofop acid reduced the electrochemical potential ofmembranes in etiolated coleoptiles of both biotypes; 50% depolarizationrequired 1 to 4 micromole diclofop acid. After removal of diclofop acid,membranes from the resistant biotype recovered polarity, whereas membranesfrom the susceptible biotype did not. Internal concentrations of diclofop acid4 h after exposing plants to herbicide were estimated to be 36 to 39micromolar in a membrane fraction and 16 to 17 micromolar in a solublefraction. Such concentrations should be sufficient to fully depolarizemembranes.  It is postulated that differences in the ability of membranes torecover from depolarization are correlated with the resistance response ofbiotype SLR 31.
58                                                     NAL Call. No.: 450 P692Cross-resistance to herbicides in annual ryegrass (Lolium rigidum). IV.Correlation between membrane effects and resistance to graminicides.Hausler, R.E.; Holtum, J.A.M.; Powles, S.B.Rockville, Md. : American Society of Plant Physiologists; 1991 Nov.Plant physiology v. 97 (3): p. 1035-1043; 1991 Nov.  Includes references.
Language:  English
Descriptors: Australia; Lolium rigidum; Biotypes; Herbicide resistant weeds;Weed control; Cross resistance; Diclofop; Fluazifop; Herbicides; Weed biology;Cell membranes; Polarity; Membrane potential
Abstract:  The herbicidally active aryloxyphenoxypropionates diclofop acid,haloxyfop acid, and fluazifop acid and the cyclohexanedione sethoxydimdepolarized membranes in coleoptiles of eight biotypes ofherbicide-susceptible and herbicide-resistant annual ryegrass (Loliumrigidum). Membrane polarity was reduced from -100 millivolts to -30 to -50millivolts. Membranes repolarized after removal of the compounds only inbiotypes with resistance to the compound added. Repolarization was notobserved in herbicide-susceptible L. rigidum, nor was it observed in biotypesresistant to triazine, triazole, triazinone, phenylurea, or sulfonylureaherbicides but not resistant to aryloxyphenoxypropionates andcyclohexanediones. Chlorsulfuron, a sulfonylurea herbicide, at a saturatingconcentration of 1 micromolar, reduced membrane polarity in all biotypesstudied by only 15 millivolts. The recovery of membrane potential followingthe removal of chlorsulfuron was restricted to chlorsulfuron-susceptible and-resistant biotypes that did not exhibit diclofop resistance. Thesedifferences in membrane responses are correlated with resistance to diclofoprather than with resistance to chlorsulfuron. It is suggested that thedifferences may reflect altered membrane properties of diclofop-resistantbiotypes. Further circumstantial evidence for dissimilarity of properties ofmembranes from diclofop-resistant and diclofop-susceptible ryegrass isprovided by observations that K+/Na+ ratios were significantly higher incoleoptiles from diclofop-resistant biotypes than in coleoptiles fromsusceptible plants. Intact and excised roots from susceptible biotypes werecapable of acidifying the external medium, whereas roots from resistantbiotypes were unable to do so. The ineluctable conclusion is that in L.rigidum the phenomena of membrane repolarization and resistance toaryloxyphenoxypropionate and cyclohexanedione herbicides are correlated.
59                                                  NAL Call. No.: 442.8 B5236Dark adapted leaves of paraquat-resistant tobacco plants emit less ultraweaklight than susceptible ones.Hideg, E.; Inaba, H.Orlando, Fla. : Academic Press; 1991 Jul31.Biochemical and biophysical research communications v. 178 (2): p. 438-443;1991 Jul31.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Leaves; Paraquat; Herbicide resistance;Biotypes; Superoxide dismutase; Dark; Light; Emission; Light intensity
Abstract:  Long term light emission was compared from leaves ofparaquat-resistant and -susceptible tobacco plants. In the minutes time scale,delayed light emission of the two biotypes was similar both in kinetics and inintensity. However, after several hours in the dark, ultraweak light emissionfrom leaves of resistant plants was about one third of the light emitted bysusceptible samples, We suggest, that this difference is due to the higheractivity of superoxide dismutase in resistant biotypes, earlier reported byTanaka et al. (1988) (Plant Cell Physiol. 29, 743-746), and propose a modelfor the mechanism of ultraweak light emission from these samples.
60                                                    NAL Call. No.: SB951.P47Deamination of metribuzin in tolerant and susceptible soybean (Glycine max)cultivars.Fedtke, C.Essex : Elsevier Applied Science Publishers; 1991.Pesticide science v. 31 (2): p. 175-183; 1991.  Includes references.
Language:  English
Descriptors: Glycine max; Cultivars; Herbicide resistance; Susceptibility;Metribuzin; Carbon; Deamination; Isotope labeling; Metabolites; Herbicideresidues
Abstract:  The deamination of metribuzin was studied in vitro in peroxisomesisolated from the leaves of soybean cultivars which were either metribuzintolerant, intermediate, or sensitive. The deamination rate observed withperoxisomes from tolerant leaves was about twice the rate observed withperoxisomes from sensitive leaves. The intermediate group was alsointermediate with respect to the in-vitro deamination rate. Tolerant andsensitive intact soybean plants were pulse-labeled with [14C]metribuzin viathe roots for 5 h. The extractable radioactivity in roots, stems and leaveswas measured and separated into metabolites after the 5 h pulse and after anadditional 24 h growth in water. The level of DA (deaminated metribuzin) wasalways significantly higher in the stems and leaves of tolerant soybean plants(4.8-10.0% of the extracted radioactivity) than in sensitive stems and leaves(1.8-2.9%). Conjugates were rapidly formed in tolerant as well as in sensitivesoybean tissues. More conjugates were found in the tolerant cultivars,especially after the 5 + 24 h incubation time. Labeled [14C]DA fed to soybeanplants via the roots was conjugated two to four times faster than[14C]metribuzin. Tolerant soybean tissue conjugated [14C]DA two to three timesfaster than sensitive tissue. The results are interpreted as showing that, intolerant soybean plants, metribuzin is metabolized via deamination andsubsequent conjugation, in addition to the well-known direct conjugation ofmetribuzin parent compound.
61                                                 NAL Call. No.: SB950.2.I3I4Developing herbicide resistance in corn.Schoper, J.; Armstrong-Gustafson, P.; McBratney, B.Urbana, Ill. : Cooperative Extension Service, Univ of Illinois atUrbana-Champaign; 1991.Illinois Agricultural Pesticides Conference summaries of presentations January8, 9, 10, 1991, Urbana, Illinois / Univ of Illinois at Urbana-Champaign, CoopExt Serv, in coop with the Illinois Natural History Survey. p. 59-60; 1991."Proceedings of the 1991 Illinois Agricultural Pesticides Conference," January8-10, 1991, Urbana, Illinois.
Language:  English
Descriptors: Zea mays; Herbicide resistance
62                                              NAL Call. No.: TP248.27.P55P52Developing herbicide resistance in crops by gene transfer technology.Stalker, D.M.New York, N.Y. : Chapman and Hall; 1991.Plant biotechnology v. 1: p. 82-104; 1991.  In the series analytic: Plantgenetic engineering / edited by D. Grierson.  Literature review.  Includesreferences.
Language:  English
Descriptors: Crops; Gene transfer; Herbicide resistance; Genetictransformation; Vectors; Plasmids; Transgenics; Agrobacterium tumefaciens;Agrobacterium rhizogenes; Direct  DNAuptake; Literature reviews
63                                                    NAL Call. No.: SB610.W39Developing herbicide-tolerant crop cultivars: introduction.Harrison, H.F. JrChampaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 613-614; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Herbicide resistance; Cultivars;Genotypes; Genetic engineering; Biotechnology
64                                                    NAL Call. No.: QH301.A76Development of herbicide tolerance in peas. I. Tissue culture and in vitroselection.Van Roggen, P.M.; Kirkwood, R.C.; Boyd, P.A.Wellesbourne, Warwick : The Association of Applied Biologists; 1991.Aspects of applied biology (27): p. 267-270; 1991.  In the series analytic:Production and protection of legumes / edited by R.J. Froud-Williams, P.Gladders, M.C. Heath, J.F. Jenkyn, C.M. Knott, A. Lane and D. Pink.  Includesreferences.
Language:  English
Descriptors: Pisum sativum; Callus; Growth; Growth inhibitors; Herbicides;Resistance; Glyphosate; Metsulfuron; Tissue culture
65                                                    NAL Call. No.: QH301.A76Development of herbicide tolerance in peas. II. Regeneration via somaticembryogenesis.Van Doorne, L.E.; Marshall, G.; Kirkwood, R.C.Wellesbourne, Warwick : The Association of Applied Biologists; 1991.Aspects of applied biology (27): p. 271-274; 1991.  In the series analytic:Production and protection of legumes / edited by R.J. Froud-Williams, P.Gladders, M.C. Heath, J.F. Jenkyn, C.M. Knott, A. Lane and D. Pink.  Includesreferences.
Language:  English
Descriptors: Pisum sativum; Cultivars; Culture media; Genotypes; Herbicideresistance; Diflufenican; Glyphosate; Metsulfuron; Somatic embryogenesis
66                                                    NAL Call. No.: QK600.M82Development of resistance in Bipolaris oryzae against edifenphos.Annamalai, P.; Lalithakumari, D.Cambridge : Cambridge University Press; 1992 Jun.Mycological research v. 96 (pt.6): p. 454-460; 1992 Jun.  Includes references.
Language:  English
Descriptors: Oryza sativa; Bipolaris; Plant pathogenic fungi; Edifenphos;Herbicide resistance; Mutants; Adaptation; Virulence; Pathogenicity; Straindifferences
67                                                    NAL Call. No.: QH301.N32Development of shade-type appearance-light intensity adaptation and regulationof the D1 protein Synechococcus.Koenig, F.New York, N.Y. : Plenum Press; 1992.NATO ASI series : Series A : Life sciences v. 226: p. 545-550; 1992.  In theseries analytic: Regulation of chloroplast biogenesis / edited by J.H.Argyroudi-Akoyunoglou. Proceedings of a NATO Advanced Research Workshop, July28-August 3, 1991, Crete, Greece.  Includes references.
Language:  English
Descriptors: Synechococcus; Biological development; Light intensity;Photosynthesis; Plant proteins; Protein synthesis; Shade; Herbicideresistance; Mutants
68                                                     NAL Call. No.: 442.8 Z8The development of sulfonylurea herbicide-resistant birdsfoot trefoil (Lotuscorniculatus) plants from in vitro selection.Pofelis, S.; Le, H.; Grant, W.F.Berlin, W. Ger. : Springer International; 1992.Theoretical and applied genetics v. 83 (4): p. 480-488; 1992.  Includesreferences.
Language:  English
Descriptors: Lotus corniculatus; In vitro selection; Herbicide resistance;Sulfonylurea herbicides; Callus; Tissue culture; Shoots; Regeneration;Inheritance; Oxo-acid-lyases; Enzyme activity; Phytotoxicity
Abstract:  Herbicide-resistant lines of birdsfoot trefoil (Lotus corniculatusL. cv 'Leo') were isolated after sequential selection at the callus, shoot,and whole plant levels to the sulfonylurea (SU) herbicide Harmony [DPX-M6316;3-[[[(4-methoxy-6methyl-1,3,5, triazine-2-yl) amino] carbonyl] amino]sulfonyl-2-thiophenecarboxylate]. In field and growth chamber tests theHarmony regenerant lines displayed an increased tolerance as compared tocontrol plants from tissue culture and controls grown from seed. Results ofevaluation of callus cultures of regenerated mutant lines signify stability ofthe resistance. Outcrossed seeds collected from field trials, and tested invitro for herbicide resistance, indicate that the trait is heritable and thatresistance may be due to reduced sensitivity of acetolactate synthase to SUinhibition. Genetically stable herbicide-resistant lines of birdsfoot trefoilwere successfully isolated using in vitro selection.
69                                                    NAL Call. No.: 64.8 C883Development of sulfonylurea-resistant rapeseed using chemical mutagenesis.Tonnemaker, K.A.; Auld, D.L.; Thill, D.C.; Mallory-Smith, C.A.; Erickson, D.A.Madison, Wis. : Crop Science Society of America; 1992 Nov.Crop science v. 32 (6): p. 1387-1391; 1992 Nov.  Includes references.
Language:  English
Descriptors: Brassica napus; Herbicide resistance; Chlorsulfuron; Metsulfuron;Screening; Induced mutations; Sulfonylurea herbicides; Cultivars; Mutants;Varietal susceptibility; Genotypes
Abstract:  Residual levels of sulfonylurea (SU) herbicides in the soil havelimited rapeseed (Brassica napus L. var. napus) production in the PacificNorthwest. In a greenhouse screening procedure, the test herbicide suppressedthe growth of susceptible rapeseed plants but allowed normal growth ofresistant plants. Mutant (M2) populations of 'Cascade', 'Bridger', and 'Cathy'winter rapeseed, 'R-500' spring rapeseed (B. rapa L. subsp. rapa), and'Tilney' spring mustard (Sinapis alba L.; syn F. hirta Moench.) were screenedwith DPX-G8311, a 5:1 mixture of the SU herbicides chlorsulfuron(2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide) and metsulfuron [(methyl1-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)-amino]carbonyl]amino]sulfonyl)benzoate]], applied preemergence at 7.5 g a.i. ha-1. Approximately243 000 M2 seedlings were screened and 178 were selected for additional tests.In progeny tests, several M3 and M4 families were identified that survived 6.5g a.i. ha-1 DPX-G8311 applied preemergence but failed to survive the same rateof DPX-G8311 applied postemergence. DPX-G8311 was applied preemergence at 0 to64 g a.i. ha-1, to one M3 and six M4 families to determine a dose X familyresponse relationship. Calculated 50% growth reduction (GR(50)) values forboth number of nodes produced and dry weight accumulation were up to 25 timesgreater for the selected M3 and M4 families than for the susceptible cultivarCascade. Rapeseed lines resistant to soil residual levels of SU herbicides butsusceptible to SU herbicide foliar applied would allow rapeseed to be plantedafter a small-grain cereal to which a SU herbicide had been applied.
70                                                     NAL Call. No.: 450 P692Developmental variability of photooxidative stress tolerance inparaquat-resistant Conyza.Amsellem, Z.; Jansen, M.A.K.; Driesenaar, A.R.J.; Gressel, J.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Dec.Plant physiology v. 103 (4): p. 1097-1106; 1993 Dec.  Includes references.
Language:  English
Descriptors: Egypt; Cabt; Conyza bonariensis; Oxidants; Detoxification; Stressresponse; Regulation; Enzyme activity; Light; Temperature; Paraquat; Herbicideresistance; Weed biology; Growth stages; Enzymes; Photoinhibition
Abstract:  Paraquat-resistant hairy fleabane (Conyza bonariensis L. Cronq.)has been extensively studied, with some contention. A single, dominant genepleiotropically controls levels of oxidant-detoxifying enzymes and toleranceto many photooxidants, to photoinhibition, and possibly to other stresses. Theweed forms a rosette on humid short days and flowers in dry long days and,thus, needs plasticity to photooxidant stresses. In a series of fourexperiments over 20 months, the resistant and susceptible biotypes werecultured in constant 10-h low-light short days at 25 degrees C. Resistance wasmeasured as recovery from paraquat. The concentration required to achieve 50%inhibition of the resistant biotype was about 30 times that of the susceptibleone just after germination, increased to > 300 times that of the susceptiblesat 10 weeks of growth, and then decreased to 20-fold, remaining constantexcept for a brief increase while bolting. Resistance increased when plantswere induced to flower by long days. The levels of plastid superoxidedismutase and of glutathione reductase were generally highest in resistantplants compared to those of the susceptibles at the times of highest paraquatresistance, but they were imperceptibly different from the susceptible type atthe times of lower paraquat resistance. Photoinhibition tolerance measured asquantum yield of oxygen evolution at ambient temperatures was highest when therelative amounts of enzymes were highest in the resistant biotype. Resistanceto photoinhibition was not detected by chlorophyll a fluorescence. Enzymelevels, photoinhibition tolerance, and paraquat resistance all increasedduring flowering in both biotypes. Imperceptibly small increases in enzymelevels would be needed for 20-fold resistance, based on the moderate enzymeincreases correlated with 300-fold resistance. Thus, it is feasible thateither these enzymes play a role in the first line of defense againstphotooxidants, or another, yet unknown mechanism(s) facilitate(s) the lowerlevel of resistance, or the enzymes and unknown mechanisms act together.
71                                                    NAL Call. No.: SB951.P49Diclofop and fenoxaprop resistance in wild oats is associated with an alteredeffect on the plasma membrane electrogenic potential.Devine, M.D.; Hall, J.C.; Romano, M.L.; Marles, M.A.S.; Thomson, L.W.;Shimabukuro, R.H.Orlando, Fla. : Academic Press; 1993 Mar.Pesticide biochemistry and physiology v. 45 (3): p. 167-177; 1993 Mar.Includes references.
Language:  English
Descriptors: Manitoba; Avena fatua; Varietal susceptibility; Diclofop;Fenoxaprop; Insecticide resistance; Resistance mechanisms; Plasma membranes;Acetyl-coa carboxylase; Inhibition; Membrane potential; Electrical activity;Wild plants
Abstract:  We have examined the mechanism of herbicide resistance in a biotypeof wild oat (Avena fatua L.) that is resistant to diclofop-methyl and manyother acetyl-coenzyme A carboxylase (ACCase) inhibitors. Resistance todiclofop-methyl and fenoxaprop-ethyl was not based on reduced uptake nor onenhanced metabolism of the herbicides to inactive products. In in vitro assaysof crude or partially purified preparations, ACCase from the resistant (UM-1)and susceptible (UM-5) biotypes was equally sensitive to diclofop, with I50values of 6.1 and 7.3 micromolar for UM-1 and UM-5, respectively.Corresponding values for fenoxaprop were 2.5 and 1.0 micromolar. These resultssuggest that the high level of resistance observed toward these herbicides isnot based on an altered target enzyme. Root tissue from both UM-1 and UM-5acidified an unbuffered bathing solution. Addition of 100 KM diclofop orfenoxaprop prevented acidification of the bathing medium by UM-1, butalkalinization occurred rapidly with UM-5. When diclofop was removed from thetreatment solution, UM-1 resumed acidification of the solution, whereas the pHof the UM-5 bathing solution continued to increase. Diclofop (50 micromolar)rapidly depolarized the cell membrane in peeled coleoptile sections, with nodifference between UM-1 and UM-5. However, when diclofop was removed from thetreatment solution, the electrogenic membrane potential was quicklyreestablished in UM-1, but remained collapsed in UM-5. These results providesupport for the hypothesis that the effect of diclofop on the plasma membranepotential is an important component of its herbicidal activity. Thereversibility of the effect of diclofop and fenoxaprop on transmembrane protonflux in UM-1 appears to be associated with resistance to these herbicides.
72                                                    NAL Call. No.: SB610.W39Differential bentazon response in cowpea (Vigna unguiculata).Harrison, H.F. Jr; Fery, R.L.Champaign, Ill. : The Weed Science Society of America; 1993 Jul.Weed technology : a journal of the Weed Science Society of America v. 7 (3):p. 756-758; 1993 Jul.  Includes references.
Language:  English
Descriptors: Vigna unguiculata; Cultivars; Germplasm; Screening; Herbicideresistance; Bentazone; Tolerance; Phytotoxicity; Varietal susceptibility; Cropdamage; Abiotic injuries; Application
73                                                    NAL Call. No.: SB610.W39Differential competitiveness of sulfonylurea resistant and susceptible pricklylettuce (Lactuca serriola).Alcocer-Ruthling, M.; Thill, D.C.; Shafii, B.Champaign, Ill. : The Society; 1992 Apr.Weed technology : a journal of the Weed Science Society of America v. 6 (2):p. 303-309; 1992 Apr.  Includes references.
Language:  English
Descriptors: Idaho; Triticum aestivum; Crop weed competition; Lactucaserriola; Herbicide resistant weeds; Sulfonylurea herbicides; Biotypes; Growthrate; Competitive ability
74                                                     NAL Call. No.: 23 AU792Differential tolerance of annual medics, Nungarin subterranean clover andhedge mustard to broadleaf herbicides.Young, R.R.; Morthorpe, K.J.; Croft, P.H.; Nicol, H.East Melbourne : Commonwealth Scientific and Industrial Research Organization;1992.Australian journal of experimental agriculture v. 32 (1): p. 49-57; 1992.Includes references.
Language:  English
Descriptors: New South Wales; Medicago; Trifolium subterraneum; Crop damage;Herbicide resistance; Phytotoxicity; Sisymbrium; Weed control; 2,4-db;Bromoxynil; Diuron; Mcpa; Terbutryn
75                                                    NAL Call. No.: SB610.W39Differential tolerance of sweet potato (Ipomoea batatas) clones to metribuzin.Motsenbocker, C.E.; Monaco, T.J.Champaign, Ill. : The Weed Science Society of America; 1993 Apr.Weed technology : a journal of the Weed Science Society of America v. 7 (2):p. 349-354; 1993 Apr.  Includes references.
Language:  English
Descriptors: North Carolina; Cabt; Ipomoea batatas; Metribuzin; Herbicideresistance; Phytotoxicity; Clones; Cultivars; Varietal susceptibility; Cropdamage; Crop yield; Yield losses; Application date; Timing; Application rates;Genetic variation
76                                                    NAL Call. No.: SB610.W39Differential toxicity of tralkoxydim in Hordeum species.Tal, A.; Benyamini, Y.; Rubin, B.Champaign, Ill. : The Weed Science Society of America; 1993 Oct.Weed technology : a journal of the Weed Science Society of America v. 7 (4):p. 946-948; 1993 Oct.  Includes references.
Language:  English
Descriptors: Hordeum vulgare; Hordeum glaucum; Hordeum spontaneum; Triticumaestivum; Phytotoxicity; Crop damage; Abiotic injuries; Tralkoxydim;Application rates; Selectivity; Wild plants; Species differences; Herbicideresistance
77                                                    NAL Call. No.: SB951.P49Direct demonstration of binding-site competition between photosystem IIinhibitors at the QB niche of the D1 protein.Jansen, M.A.K.; Mattoo, A.K.; Malkin, S.; Edelman, M.Orlando, Fla. : Academic Press; 1993 May.Pesticide biochemistry and physiology v. 46 (1): p. 78-83; 1993 May.  Includesreferences.
Language:  English
Descriptors: Photosystem ii; Membranes; Proteins; Binding site; Electrontransfer; Diuron; Inhibitors; Protein degradation; Inhibition; Solanum nigrum;Spirodela oligorhiza; Biotypes; Herbicide resistance
Abstract:  Inhibitors of photosystem II function have been shown to blockelectron flow in vitro by competitively displacing plastoquinone from the Q(B)niche on the D1 protein. Few studies have tested this well-accepted concept invivo and none in higher plants. The D1 protein degradation assay was used todirectly demonstrate, in vivo, the displacement of diuron by bromonitrothymol(BNT) at the level of the Q(B) niche. We show that diuron blocks D1degradation less effectively in the presence of BNT, and that this effect ofBNT can be nullified by increasing the diuron concentration. These datadirectly demonstrate binding-site competition at the level of the Q(B) niche,under the complex physiological conditions of the intact higher plant.
78                                                     NAL Call. No.: 79.8 W41Distribution and characteristics of triazine-resistant powell amaranth(Amaranthus powellii) in Idaho.Eberlein, C.V.; Al-Khatib, K.; Guttieri, M.J.; Fuerst, E.P.Champaign, Ill. : Weed Science Society of America; 1992.Weed science v. 40 (4): p. 507-512; 1992.  Includes references.
Language:  English
Descriptors: Idaho; Amaranthus powellii; Herbicide resistance; Atrazine;Metribuzin; Diuron; Binding site; Thylakoids; Resistance mechanisms; Geneticanalysis; Chloroplast genetics; Genes; Mutations; Nucleotide sequences; Aminoacid sequences; Biotypes; Geographical distribution
Abstract:  A triazine-resistant (TR) biotype of Powell amaranth was discoveredin 1989 in a potato field treated with metribuzin. A survey of allagricultural counties in Idaho showed that the TR Powell amaranth infestationwas localized in the southeastern corner of Gooding county in southern Idaho.To determine the mechanism of triazine resistance, I50 values for inhibitionof photosystem II were determined for atrazine, metribuzin, and diuron usingthylakoids isolated from TR and triazine-susceptible (TS) biotypes. TR/TSratios based on I50 values were 134 for atrazine, 62 for metribuzin, and 1.9for diuron. Results of binding studies with atrazine and metribuzin wereconsistent with the I50 studies, indicating that resistance was due to reducedbinding of triazines to the thylakoid membrane D1 protein. Sequencing thechloroplast psbA gene from TR and TS biotypes revealed a serine 264 to glycinechange in the TR biotype. The mutation presumably resulted in reduced hydrogenbonding between triazine herbicides and the D1 protein.
79                                                     NAL Call. No.: 79.8 W41DNA sequence variation in domain A of the acetolactate synthase genes ofherbicide-resistant and -susceptible weed biotypes.Guttieri, M.J.; Eberlein, C.V.; Mallory-Smith, C.A.; Thill, D.C.; Hoffman,D.L.Champaign, Ill. : Weed Science Society of America; 1992.Weed science v. 40 (4): p. 670-676; 1992.  Includes references.
Language:  English
Descriptors: Kochia scoparia; Lactuca serriola; Salsola iberica; Herbicideresistant weeds; Biotypes; Chlorsulfuron; Herbicide resistance; Genes;Nucleotide sequences; Amino acid sequences; Genetic variation; Weed biology
Abstract:  The DNA sequence of a 196 base pair (bp) region of the acetolactatesynthase (ALS) genes of three weed species, kochia, prickly lettuce, andRussian thistle was determined. This region encompasses the coding sequencefor Domain A, a region of the amino acid sequence previously demonstrated toplay a pivotal role in conferring resistance to herbicides that inhibit ALS.The Domain A DNA sequence from a chlorsulfuron-resistant (R) prickly lettucebiotype from Idaho differed from that of a chlorsulfuron-susceptible (S)biotype by a single point mutation, which substituted a histidine for aproline. The Domain A DNA sequence from an R kochia biotype from Kansas alsodiffered from that of an S biotype by a single point mutation in the sameproline codon. This point mutation, however, conferred substitution ofthreonine for proline. Two different ALS-homologous sequences were isolatedfrom an R biotype of Russian thistle. Neither sequence encoded amino acidsubstitutions in Domain A that differed from the consensus S sequence. The DNAsequence variation among the R and S kochia biotypes was used to characterizesix Ada County, Idaho, kochia collections for correlation between phenotypicchlorsulfuron susceptibility and restriction digest patterns (RFLPs) ofpolymerase chain reaction amplification products. Most collections showedexcellent correspondence between the RFLP patterns and the phenotypic responseto chlorsulfuron application. However, one entirely R collection had the RFLPpattern of the S biotype, suggesting that resistance was not due to mutationin the proline codon.
80                                                     NAL Call. No.: SB249.N6Documentation of graminicide-resistant johnsongrass in cotton.Snipes, C.E.; Barrentine, W.L.; Smeda, R.J.Memphis, Tenn. : National Cotton Council of America, 1991-; 1993.Proceedings / v. 3: p. 1508; 1993.  Meeting held January 10-14, 1993, NewOrleans, Louisiana.
Language:  English
Descriptors: Sorghum halepense; Gossypium; Herbicide resistance
81                                                      NAL Call. No.: 472 N21Ecology of transgenic oilseed rape in natural habitats.Crawley, M.J.; Hails, R.S.; Rees, M.; Kohn, D.; Buxton, J.London : Macmillan Magazines Ltd; 1993 Jun.Nature v. 363 (6430): p. 620-623; 1993 Jun.  Includes references.
Language:  English
Descriptors: Brassica napus var. oleifera; Transgenics; Genetic engineering;Ecology
Abstract:  Concerns about genetically engineered crop plants centre on threeconjectural risks: that transgenic crop plants will become weeds ofagriculture or invasive of natural habitats; that their engineered genes willbe transferred by pollen to wild relatives whose hybrid offspring will thenbecome more weedy or more invasive; or that the engineered plants will be adirect hazard to humans, domestic animals or beneficial wild organisms (toxicor allergenic, for example). Here we describe an experimental protocol forassessing the invasiveness of plants. The object is to determine whethergenetic engineering for herbicide tolerance affects the likelihood of oilseedrape becoming invasive of natural habitats. By estimating the demographicparameters of transgenic and conventional oilseed rape growing in a variety ofhabitats and under a range of climatic conditions, we obtain a directcomparison of the ecological performance of three different genetic lines(control, kanamycin-tolerant transgenics and herbicide-tolerant transgeniclines). Despite substantial variation in seed survival, plant growth and seedproduction between sites and across experimental treatments, there was noindication that genetic engineering for kanamycin tolerance or herbicidetolerance increased the invasive potential of oilseed rape. In those cases inwhich there were significant differences (such as seed survival on burial),transgenic lines were less invasive and less persistent than theirconventional counterparts.
82                                                    NAL Call. No.: 56.8 J822Economic and environmental implications of herbicide-tolerant corn andprocessing tomatoes.Hayenga, M.; Thompson, L.C.; Chase, C.; Kaaria, S.Ankeny, Iowa : Soil and Water Conservation Society of America; 1992 Sep.Journal of soil and water conservation v. 47 (5): p. 411-417; 1992 Sep.Includes references.
Language:  English
Descriptors: Zea mays; Lycopersicon esculentum; Hybrid varieties; Herbicideresistance; Crop production; Economic impact; Production costs; Environmentalimpact; Weed control
83                                                      NAL Call. No.: 450 C16Effect of diclofop and HOE-6001 on amylolytic enzyme activities of malt.McMullan, P.M.; Noll, J.; Therrien, M.C.Ottawa : Agricultural Institute of Canada; 1992 Apr.Canadian journal of plant science; Revue canadienne de phytotechnie v. 72 (2):p. 435-438; 1992 Apr.  Includes references.
Language:  English
Descriptors: Manitoba; Hordeum vulgare; Genotypes; Alpha-amylase;Alpha-glucosidase; Diclofop; Fenoxaprop; Herbicide resistance; Avena fatua;Setaria viridis; Weed control
84                                                     NAL Call. No.: 450 P692Effect of diclofop on the membrane potentials of herbicide-resistant and-susceptible annual ryegrass root tips.Shimabukuro, R.H.; Hoffer, B.L.Rockville, Md. : American Society of Plant Physiologists; 1992 Apr.Plant physiology v. 98 (4): p. 1415-1422; 1992 Apr.  Includes references.
Language:  English
Descriptors: Australia; Lolium rigidum; Root tips; Plasmalemma; Membranepotential; Diclofop; Herbicide resistance; Susceptibility; Phytotoxicity
Abstract:  Electrophysiological measurements were made on root tip cells inthe elongation zone of diclofop-methyl-resistant (SR4/84) and -susceptible(SRS2) biotypes of annual ryegrass (Lolium rigidum Gaud.) from Australia. Thephytotoxic action of diclofop-methyl (methyl2-[4-(2',4'-dichlorophenoxy)phenoxy]propanoate) on susceptible whole plantswas completely reversed by a simultaneous application of2,4-dichlorophenoxyacetic acid (dimethylamine salt). The phytotoxic acidmetabolite, diclofop (50 micromolar), depolarized membrane potentials of bothbiotypes to a steady-state level within 10 to 15 minutes. Repolarization ofthe membrane potential occurred only in the resistant biotype followingremoval of diclofop. The resistant biotype has an intrinsic ability toreestablish the electrogenic membrane potential, whereas the susceptiblebiotype required an exogeneous source of IAA to induce partial repolarization.Both biotypes were susceptible to depolarization bycarbonylcyanide-m-chlorophenylhydrazone (CCCP), and their membrane potentialsrecovered upon removal of CCCP. A 15-minute pretreatment withp-chloromercuribenzenesulphonic acid (PCMBS) blocked the depolarizing actionof diclofop in both biotypes. However, PCMBS had no effect on the activity ofCCCP. The action of diclofop appears to involve a site-specific interaction atthe plasmalemma in both Lolium biotypes to cause the increased influx ofprotons into sensitive cells. The differential response of membranedepolarization and repolarization to diclofop treatment may be a significantinitial reaction in the eventual phytotoxic action of the herbicide.
85                                                    NAL Call. No.: SB610.W39Effect of ethalfluralin and other herbicides on trifluralin-resistant greenfoxtail (Setaria viridis).Beckie, H.J.; Morrison, I.N.Champaign, Ill. : The Weed Science Society of America; 1993 Jan.Weed technology : a journal of the Weed Science Society of America v. 7 (1):p. 6-14; 1993 Jan.  Includes references.
Language:  English
Descriptors: Manitoba; Cabt; Setaria viridis; Herbicide resistant weeds;Trifluralin; Herbicide resistance; Biotypes; Weed control; Chemical control;Ethalfluralin; Dinitroaniline herbicides; Oryzalin; Isopropalin;Pendimethalin; Prodiamine; Propyzamide; Pyridine herbicides; Mitosis;Metabolic inhibitors; Propanil; Diclofop; Fenoxaprop; Fluazifop; Dalapon;Sethoxydim; Linuron; Eptc; Cross resistance; Phytotoxicity; Triticum aestivum;Brassica napus
86                                                     NAL Call. No.: 79.8 W41Effect of field violet (Viola arvensis) growth stage on uptake, translocation,and metabolism of terbacil.Doohan, D.J.; Monaco, T.J.; Sheets, T.J.Champaign, Ill. : Weed Science Society of America; 1992 Apr.Weed science v. 40 (2): p. 180-183; 1992 Apr.  Includes references.
Language:  English
Descriptors: Viola arvensis; Seedling stage; Maturity stage; Terbacil;Absorption; Translocation; Metabolic detoxification; Metabolism; Herbicideresistant weeds; Metabolites; Herbicide resistance; Variation
Abstract:  Uptake, translocation, and metabolism of 14C-terbacil wasinvestigated in 12-leaf (tolerant) and 3-leaf (susceptible) field violetplants. Field violets with 12 leaves absorbed less 14C-terbacil g-1 of freshweight from solution culture than did plants with three leaves. Plants withthree leaves translocated twice as much radioactivity to foliage than didplants with 12 leaves. Most 14C in roots (77%) and foliage (57%) of fieldviolet plants with 12 leaves was in polar metabolites. Metabolism studiesindicated that most 14C (79%) in foliage extracts from field violet plantswith three leaves was 14C-terbacil. Polar metabolites were not detected inroots of field violet plants with three leaves.
87                                                     NAL Call. No.: 450 P693Effect of four classes of herbicides on growth and acetolactate-synthaseactivity in several variants of Arabidopsis thaliana.Mourad, G.; King, J.Berlin : Springer-Verlag; 1992.Planta v. 188 (4): p. 491-497; 1992.  Includes references.
Language:  English
Descriptors: Arabidopsis thaliana; Ligases; Enzyme activity; Inhibition;Chlorsulfuron; Sulfonamides; Imazapyr; Benzoic acid herbicides; Mutants;Mutations; Loci; Alleles; Herbicide resistance; Binding site; Cross resistance
Abstract:  We have isolated a triazolopyrimidine-resistant mutant csr1-2, ofArabidopsis thaliana (L.) Heynh. Here, we compare csr1-2 with the previouslyisolated mutants csr1 and csr1-1, and with wild-type Arabidopsis for responsesto members of four classes of herbicides, namely, sulfonylureas,triazolopyrimidines, imidazolinones, and pyrimidyl-oxy-benzoates. Twoseparable herbicide-binding sites have been identified previously on theprotein of acetolactate synthase (ALS). Here, the mutation giving rise tocsr1, originating in a coding sequence towards the 5' end of the ALS gene, andthat in csr1-2, affected the inhibitory action on growth and ALS activity ofsulfonylurea and triazolopyrimidine herbicides but not that of theimidazolinones or pyrimidyl-oxybenzoates. The other mutation, in csr1-1,originating in a coding sequence towards the 3' end of the ALS gene, affectedthe inhibitory action of imidazolinones and pyrimidyl-oxy-benzoates but notthat of the sulfonylureas or triazolopyrimidines. Additional, stimulatoryeffects of some of these herbicides on growth of seedlings was unrelated totheir effect on their primary target, ALS. The conclusion from theseobservations is that one of the two previously identified herbicide-bindingsites may bind sulfonylureas and triazolopyrimidines while the other may bindimidazolinones and pyrimidyl-oxybenzoates within a herbicide-binding domain onthe ALS enzyme. Such a comparative study using near-isogenic mutants from thesame species allows not only the further definition of the domain of herbicidebinding on ALS but also could aid investigation of the relationship betweenherbicide-, substrate-, and allosteric-binding sites on this enzyme.
88                                                   NAL Call. No.: 511 P444AEEffect of treating plants with abscisic acid on its concentration in leavesand resistance of three pea cultivars to the herbicide 2,4-D.Melekhov, E.I.; Lavrent'ev, A.A.New York, N.Y. : Consultants Bureau; 1992.Doklady : botanical sciences - Akademiia nauk SSSR v. 319/321: p. 79-82; 1992. Translated from: Akademiia Nauk SSSR. Doklady. v. 319/321, 1991, p.1273-1277, (511 P444A).  Includes references.
Language:  English; Russian
Descriptors: Pisum sativum; Cultivars; Herbicide resistance; 2,4-d; Plants;Treatment; Abscisic acid; Growth chambers; Survival
89                                                    NAL Call. No.: SB610.W39Effective kill of trifluralin-susceptible and -susceptible agreen foxtail(Setaria viridis).Beckie, H.J.; Morrison, I.N.Champaign, Ill. : The Weed Science Society of America; 1993 Jan.Weed technology : a journal of the Weed Science Society of America v. 7 (1):p. 15-22; 1993 Jan.  Includes references.
Language:  English
Descriptors: Manitoba; Cabt; Triticum aestivum; Brassica napus; Weed control;Setaria viridis; Herbicide resistant weeds; Trifluralin; Herbicide resistance;Biotypes; Application rates; Chemical control; Application methods;Phytotoxicity; Susceptibility
90                                                    NAL Call. No.: 450 J8224Effects of 4-chloro-2-methylphenoxypropionate (an auxin analogue) on plasmamembrane ATPase activity in herbicide-resistant and herbicide-susceptiblebiotypes of Stellaria media L.Coupland, D.; Cooke, D.T.; James, C.S.Oxford : Oxford University Press; 1991 Aug.Journal of experimental botany v. 42 (241): p. 1065-1071; 1991 Aug.  Includesreferences.
Language:  English
Descriptors: Stellaria media; Mecoprop; Herbicide resistant weeds; Herbicideresistance; Adenosinetriphosphatase; Enzyme activity; Plasma membranes; Atp;Hydrolysis; Biotypes; Proton pump; Phospholipids; Sterols
Abstract:  ATPase activity was examined in plasma membrane (PM) fractionsprepared from mecoprop-resistant and -susceptible biotypes of Stellaria mediaL. (chickweed). Treatment with the herbicide caused an 18% increase in ATPhydrolysis, but this was not significantly different from control plants andwas similar for both biotypes. However, there was an overall significantbiotype effect, herbicide-resistant plants having greater enzyme activity thansusceptible ones. Proton-pumping was readily demonstrated in PM fractionsobtained from both biotypes using the fluorescent probeamino-chloro-methoxyacridine (ACMA), indicating a relatively large proportionof 'inside-out' vesicles. Proton-pumping was significantly greater in PMpreparations obtained from the resistant compared with susceptible plants. Thedifferences in ATPase activity between the two biotypes could not beattributed to differences in the main sterol or phospholipid components of thePM. There were no effects of the herbicide on ATP hydrolysis in vitro, butproton-pumping was affected in a herbicide concentration-dependent manner. At1.0 mol m-6 mecoprop caused an increase in the rate of proton-pumping, whereasat 10 and 100 mol m-6, an inhibition in this rate was observed. Both biotypesbehaved similarly, irrespective of mecoprop concentration. These data indicatethat mecoprop resistance in chickweed is unlikely to be due to a direct effectof the herbicide on PM H+ -ATPase activity.
91                                                     NAL Call. No.: 450 P692Effects of acetyl-coenzyme A carboxylase inhibitors on root cell transmembraneelectric potentials in graminicide-tolerant and -susceptible corn (Zea maysL.).Dotray, P.A.; DiTomaso, J.M.; Gronwald, J.W.; Wyse, D.L.; Kochian, L.V.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Nov.Plant physiology v. 103 (3): p. 919-924; 1993 Nov.  Includes references.
Language:  English
Descriptors: Zea mays; Lines; Herbicides; Tolerance; Susceptibility; Membranepotential; Soil ph
Abstract:  Herbicidal activity of aryloxyphenoxypropionate andcyclohexanedione herbicides (graminicides) has been proposed to involve twomechanisms: inhibition of acetyl-coenzyme A carboxylase (ACCase) anddepolarization of cell membrane potential. We examined the effect ofaryloxyphenoxypropionates (diclofop and haloxyfop) and cyclohexanediones(sethoxydim and clethodim) on root cortical cell membrane potential ofgraminicide-susceptible and -tolerant corn (Zea mays L.) lines. Thegraminicide-tolerant corn line contained a herbicide-insensitive form ofACCase. The effect of the herbicides on membrane potential was similar in bothcorn lines. At a concentration of 50micromolar, the cyclohexanediones hadlittle or no effect on the membrane potential of root cells. At pH 6, 50micromolar diclofop, but not haloxyfop, depolarized membrane potential,whereas both herbicides (50 micromolar) dramatically depolarized membranepotential at pH 5. Repolarization of membrane potential after removal ofhaloxyfop and diclofop from the treatment solution was incomplete at pH 5.However, at pH 6 nearly complete repolarization of membrane potential occurredafter removal of diclofop. In graminicide-susceptible corn, root growth wassignificantly inhibited by a 24-h exposure to 1 micromolar haloxyfop orsethoxydim, but cell membrane potential was unaffected. In gramincide-tolerantcorn, sethoxydim treatment (1 micromolar, 48 h) had no effect on root growth,whereas haloxyfop (1 micromolar, 48 h) inhibited root growth by 78%. However,membrane potential was the same in roots treated with 1 micromolar haloxyfopor sethoxydim. The results of this study indicate that graminicide tolerancein the corn line used in this investigation is not related to an alteredresponse at the cell membrane level as has been demonstrated with otherresistant species.
92                                                    NAL Call. No.: SB951.P49Effects of isoxaben on sensitive ant tolerant plant cell cultures. I.Metabolic fate of isoxaben.Corio-Costet, M.F.; Dall'Agnese, M.; Scalla, R.Orlando, Fla. : Academic Press; 1991 Jul.Pesticide biochemistry and physiology v. 40 (3): p. 246-254; 1991 Jul.Includes references.
Language:  English
Descriptors: Triticum aestivum; Glycine max; Cell suspensions; Cell cultures;Isoxaben; Phytotoxicity; Herbicide resistance; Susceptibility; Linedifferences; Metabolic detoxification; Metabolites
Abstract:  A soybean cell line tolerance to isoxaben was isolated by callusselection in herbicide-containing medium. The growth of tolerant suspensioncells was not affected by 10 micromoles isoxaben, which prevented the growthof wild-type cultures. The growth of a wheat cell culture was little affectedby isoxaben, in accordance to the tolerance of wheat plants to the herbicide.The metabolic fate of labeled isoxaben in the three types of cultures wasexamined. By comparison with the sensitive, wild-type soybean cell culture,the tolerance of the selected soybean cell culture and that of wheat cellculture cannot be explained by either quantitative or qualitative differencesof herbicide metabolism. These results favor the hypothesis that thesensitivity or tolerance of the cell cultures is determined at the level ofthe cellular target of the herbicide.
93                                                    NAL Call. No.: SB951.P49Effects of isoxaben on senstitive and tolerant plant cell cultures. II.Cellular alterations and inhibition on the synthesis of acid-insoluble cellwall material.Corio-Costet, M.F.; Lherminier, J.; Scalla, R.Orlando, Fla. : Academic Press; 1991 Jul.Pesticide biochemistry and physiology v. 40 (3): p. 255-265; 1991 Jul.Includes references.
Language:  English
Descriptors: Triticum aestivum; Glycine max; Cell suspensions; Cell cultures;Lines; Line differences; Susceptibility; Herbicide resistance; Phytotoxicity;Isoxaben; Dichlobenil; Mode of action; Cell walls; Biosynthesis; Metabolicinhibitors; Cell wall components; Cellulose; Glucose; Plasma membranes; Cellultrastructure
Abstract:  The herbicide isoxaben is selectively phytotoxic to dicotyledonousplants, whereas most monocots are tolerant. We previously selected a soybeancell culture tolerant to isoxaben. Some effects of the herbicide on wild-typesoybean cells, tolerant soybean cells, and wheat cells were compared.Cytological observations showed that isoxaben induced some disorganization ofsensitive soybean cells, especially at the plasma membrane-cell wallinterface. Tolerant soybean cells appeared normal in the presence of isoxaben.The growth of wild-type soybean cells was roughly equally sensitive toisoxaben as to dichlobenil, a cellulose synthesis inhibitor. By comparison,the selected soybean line and a wheat cell culture were less sensitive toisoxaben than to dichlobenil. Glucose incorporation into acid-insoluble cellwall material was more inhibited by isoxaben than by dichlobenil in thewild-type soybean cell culture. In the tolerant soybean cell culture, theincorporation was slightly inhibited by isoxaben, but remained sensitive todichlobenil. In the wheat cell culture, dichlobenil was also more inhibitorybut only at high concentrations. Other compounds, inhibitors of cellulosebiosynthesis, of glycosylation of lipids or protein, or of cell division,either had no effect on the synthesis of acid-insoluble cell wall material orexerted apparently unspecific inhibitions. The results are consistent withisoxaben inhibiting the synthesis of a cell wall polysaccharide, which couldbe cellulose.
94                                                      NAL Call. No.: 450 AN7Effects of mecoprop (an auxin analogue) on ethylene evolution and epinasty intwo biotypes of Stellaria media.Coupland, D.; Jackson, M.B.London : Academic Press; 1991 Aug.Annals of botany v. 68 (2): p. 167-172; 1991 Aug.  Includes references.
Language:  English
Descriptors: Stellaria media; Lycopersicon esculentum; Mecoprop; Herbicideresistance; Phytotoxicity; Ethylene production; Epinasty; Biotypes; Geneticvariation
Abstract:  Petiolar epinasty and the production of ethylene (ethene) werestudied in chickweed biotypes, Stellaria media, treated with the herbicide andauxin analogue (RS)-2-(4-chloro-o-tolyloxy)propionic acid, potassium salt,common name mecoprop. This compound caused severe epinasty and stimulated theproduction of ethylene from shoot explants. However, when intact plants weretreated with ethylene, the leaves became only slightly epinastic. The ethyleneprecursor, 1-aminocyclopropane-1-carboxylic acid (ACC), at concentrationswhich stimulated the release of ethylene, was equally ineffective in causingepinasty. Furthermore, 2,5-norbornadiene, a specific, competitive inhibitor ofethylene action, only partly alleviated mecoprop-induced epinasty. Theresponses observed in chickweed were compared with those produced in tomatoplants. ACC induced epinasty in tomato within 2 h and these symptoms werecompletely inhibited by norbornadiene. However, as in chickweed, the inhibitorgave only partial reversal of mecoprop-induced epinasty, implying that theepinastic response caused by the herbicide was not attributable to ethylenealone. We therefore suggest that mecoprop-induced epinasty is a result of thecombined ethylene-stimulating and growth-promoting properties of theherbicide. Mecoprop-stimulated ethylene evolution was initially significantlygreater in a herbicide-resistant, compared with a more susceptible biotype ofchickweed. The significance of this finding is discussed in relation to themechanism of mecoprop resistance in chickweed.
95                                                     NAL Call. No.: 450 P692Effects on photosystem II function, photoinhibition, and plant performance ofthe spontaneous mutation of serine-264 in the photosystem II reaction centerD1 protein in triazine-resistant Brassica napus L.Sundby, C.; Chow, W.S.; Anderson, J.M.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Sep.Plant physiology v. 103 (1): p. 105-113; 1993 Sep.  Includes references.
Language:  English
Descriptors: Brassica napus; Mutations; Photoinhibition; Photosystem ii;Serine; Triazine herbicides; Weed control; Yield losses; Herbicide resistance
Abstract:  Wild-type and an atrazine-resistant biotype of Brassica napus, inwhich a glycine is substituted for the serine-264 of the D1 protein, weregrown over a wide range of constant irradiances in a growth cabinet. In theabsence of serine-264, the function of photosystem II (PSII) was changed asreflected by changes in chlorophyll fluorescence parameters and inphotosynthetic oxygen-evolving activity. The photochemical quenchingcoefficient was lower, showing that a larger proportion of the primary quinoneacceptor is reduced at all irradiances. At low actinic irradiances, thenonphotochemical quenching coefficient was higher, showing a greater tendencyfor heat emission. Decreased rates of light-limited photosynthesis (quantumyield) and lower oxygen yields per single-turnover flash were also observed.These changes were observed even when the plants had been grown under lowirradiances, indicating that the changes in PSII function are direct and notconsequences of photoinhibition. In spite of the lowered PSII efficiency underlight-limiting conditions, the light-saturated photosynthesis rate of theatrazine-resistant mutant was similar to that of the wild type. An enhancedsusceptibility to photoinhibition was observed for the atrazine-resistantbiotype compared to the wild type when plants were grown under high andintermediate, but not low, irradiance. We conclude that the replacement ofserine by glycine in the D1 protein has a direct effect on PSII function,which in turn causes increased photoinhibitory damage and increased rates ofturnover of the D1 protein. Both the intrinsic lowering of light-limitedphotosynthetic efficiency and the increased sensitivity to photoinhibitionprobably contribute to reduced crop yields in the field, to different extents,depending on growth conditions.
96                                                     NAL Call. No.: 442.8 Z8Engineering 2,4-D resistance into cotton.Bayley, C.; Trolinder, N.; Ray, C.; Morgan, M.; Quesenberry, J.E.; Ow, D.W.Berlin, W. Ger. : Springer International; 1992.Theoretical and applied genetics v. 83 (5): p. 645-649; 1992.  Includesreferences.
Language:  English
Descriptors: Gossypium hirsutum; Nicotiana tabacum; Agrobacterium tumefaciens;Alcaligenes; Genetic transformation; Transgenics; Gene transfer; Genes;Oxidoreductases; 2,4-d; Herbicide resistance; Inheritance; Enzyme activity
Abstract:  To reduce damage by drift-levels of the herbicide2,4-dichlorophenoxyacetic acid, we have engineered the 2,4-D resistance traitinto cotton (Gossypium hirsutum L.). The 2,4-D monooxygenase gene tfdA fromAlcaligenes eutrophus plasmid pJP5 was isolated, modified and expressed intransgenic tobacco and cotton plants. Analyses of the transgenic progenyshowed stable transmission of the chimeric tfdA gene and production of active2,4-D monooxygenase. Cotton plants obtained were tolerant to 3 times the fieldlevel of 2,4-D used for wheat, corn, sorghum and pasture crops.
97                                                      NAL Call. No.: QD1.A45Engineering crop resistance to the naturally occurring glutamine synthetaseinhibitor phophinothricin.Mullner, H.; Eckes, P.; Donn, G.Washington, D.C. : The Society; 1993.ACS Symposium series - American Chemical Society (524): p. 38-47; 1993.  Inthe series analytic: Pest control with enhanced environmental safety / editedby S.O. Duke, J.J. Menn, and J.R. Plimmer.  Includes references.
Language:  English
Descriptors: Weed control; Herbicide resistance; Genetic engineering; Genetransfer; Glufosinate
Abstract:  Chemical plant protection will be always needed, but theapplication of gene technology can reduce the impact of agriculture to theenvironment and offer new attractive systems for weed control to the farmer.The non-selective herbicide glufosinate exhibit desirable properties, whichmakes it suitable for weed control in crops. By transferring a microbialresistance gene from the producer of the active principle of glufosinate,sensitive crops like corn, oilseed-rape, soy bean and sugarbeet could be maderesistant. In comparison to present, on soil herbicides based weed controlsystems, the flexibility in the application of the post-emergent foliarherbicide glufosinate in resistant crops comes closer to an ideal system. Theintroduction of this new system will be another important step towards anagriculture with reduced impact on the environment.
98                                                 NAL Call. No.: SB123.57.M64Engineering microbial herbicide detoxification genes in higher plants.Lyon, B.R.Molecular approaches to crop improvement / edited by E.S. Dennis and D.J.Llewellyn. p. 79-108; 1991. (Plant gene research).  Literature review.Includes references.
Language:  English
Descriptors: Crops; Nicotiana tabacum; Genetic engineering; Transgenics;Genetic transformation; Herbicide resistance; Herbicides; 2,4-d; Enzymes;Microbial degradation; Oxygenases; Genes; Alcaligenes; Literature reviews
99                                                     NAL Call. No.: 442.8 Z8Enhanced oxidative-stress defense in transgenic potato expressing tomato Cu,Znsuperoxide dismutases.Perl, A.; Perl-Treves, R.; Galili, S.; Aviv, D.; Shalgi, E.; Malkin, S.;Galun, E.Berlin, W. Ger. : Springer International; 1993 Jan.Theoretical and applied genetics v. 85 (5): p. 568-576; 1993 Jan.  Includesreferences.
Language:  English
Descriptors: Solanum tuberosum; Lycopersicon esculentum; Genetictransformation; Transgenics; Gene transfer; Dna; Superoxide dismutase; Copper;Zinc; Gene expression; Enzyme activity; Herbicide resistance; Paraquat;Oxygen; Phototoxicity; Photosynthesis; Stress; Roots; Shoots; Organ culture
Abstract:  The two cDNAs coding for the cytosolic (cyt) and thechloroplast-located (chl) Cu,Zn superoxide dismutases (SODs) of tomato(Perl-Treves et al. 1988) were cloned into respective binary vectors andmobilized into Agrobacterium strains. Potato tuber discs were infected witheither of the two agrobacterial strains and cultured on selective mediumcontaining kanaymcin. The integration of either of the cyt or the chl SODtransgenes was verified by Southern-blot hybridization. The enzymatic activityof the additional tomato chl Cu,Zn SOD could be distinguished from endogenousSOD activity since the latter isozyme migrated faster on SOD-activity gels.Several transgenic potato lines harboring either the cyt or the chl SOD genesof tomato showed elevated tolerance to the superoxide-generating herbicideparaquat (methyl viologen). After exposure of shoots to paraquat, tolerancewas recorded either by scoring symptoms visually or by measurements ofphotosynthesis using the photoacoustic method. Root cultures from transgeniclines that harbored the additional cyt Cu,Zn SOD gene of tomato were tolerantto methyl viologen up to 10(-5) M; a lower tolerance was recorded in roots oftransgenic lines that expressed the additional chl Cu,Zn SOD of tomato.
100                                                   NAL Call. No.: SB610.W39Environmental concerns with the development of herbicide-tolerant plants.Goldburg, R.J.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 647-652; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Forest trees; Herbicide resistance;Herbicides; Weed control; Environmental impact; Groundwater pollution; Publichealth; Food safety; Nontarget effects; Private sector; Public sector; Policy
101                                                   NAL Call. No.: SB610.W39EPA's response to resistance management and herbicide--tolerant crop issues.Horne, D.M.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 657-661; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: U.S.A.; Transgenic plants; Herbicide resistance; Public agencies;Biotechnology; Regulation; Legislation
102                                                   NAL Call. No.: HT401.A36Ethical and environmental consideration in the release of herbicide resistantcrops.Dekker, J.; Comstock, G.Gainesville, Fla. : Agriculture and Human Values, Inc; 1992.Agriculture and human values v. 9 (3): p. 31-43; 1992.  Includes references.
Language:  English
Descriptors: Herbicide resistance; Ethics; Risk; Crop production; Economicviability
103                                                   NAL Call. No.: SB951.P49Ethylene biosynthesis following foliar application of picloram to biotypes ofwild mustard (Sinapis arvensis L.) susceptible or resistant to auxinicherbicides.Hall, J.C.; Alam, S.M.M.; Murr, D.P.Orlando, Fla. : Academic Press; 1993 Sep.Pesticide biochemistry and physiology v. 47 (1): p. 36-43; 1993 Sep.  Includesreferences.
Language:  English
Descriptors: Sinapis arvensis; Biotypes; Herbicide resistance; Susceptibility;Picloram; Biosynthesis; Ethylene production; Acc; Growth regulators; Enzymes;Enzyme activity; Epinasty
Abstract:  Following foliar application of picloram (100 g a.i. ha(-1)) tobiotypes of wild mustard (Sinapis arvensis L.) resistant (R) or susceptible(S) to auxinic herbicides, ethylene and its precursors, ACC(1-aminocyclopropane-1-carboxylic acid) and MAAC(1-malonylaminocyclopropane-1-carboxylic acid), as well as ACC synthase werequantified. Severe epinasty occurred within 24 hr after picloram was appliedto the S biotype with concomitant increases in ACC synthase, ACC, MACC, andethylene. No epinasty occurred in the R biotype, nor was there an increaseabove basal levels of ACC synthase, ACC, MACC, and ethylene in this biotype.Both biotypes became epinastic when fumigated with 120 microliter liter(-1) ofethylene. Furthermore, when the tissues from both biotypes were supplied withexogenous ACC (1 millimole) after pretreatment with aminooxyacetic acid (1millimole), an inhibitor of ACC synthase, both biotypes produced ethylenethereby indicating that ethylene-forming enzyme was not impaired in theresistant biotype. These results suggest that picloram-induced ethylenebiosynthesis in the S biotype of wild mustard results from de novo synthesisof ACC synthase; however, this is not the case in the R biotype. Furthermore,sensitivity differences between the two biotypes are related to regulation ofpicloram-induced ethylene biosynthesis and resistance may be due to adifferent interaction of the herbicide with primary target site(s) such as theauxin-binding protein(s).
104                                                    NAL Call. No.: 79.9 W52Evaluating wild oat seed collections for herbicide resistance.Trunkle, P.A.; Fay, P.K.; Dyer, W.E.; Davis, E.S.Reno, Nev. : The Society; 1992.Proceedings - Western Society of Weed Science v. 45: p. 53-54; 1992.  Meetingheld March 10-12, 1992, in Salt Lake City, Utah.
Language:  English
Descriptors: Avena sativa; Herbicide resistance
105                                                     NAL Call. No.: 450 C16Evaluation of oat germplasm for resistance to diclofop-methyl.Kibite, S.; Harker, K.N.Ottawa : Agricultural Institute of Canada; 1991 Apr.Canadian journal of plant science; Revue canadienne de phytotechnie v. 71 (2):p. 491-495; 1991 Apr.  Includes references.
Language:  English
Descriptors: Alberta; Australia; Avena sativa; Avena fatua; Genotypes; Varietytrials; Germplasm; Selection; Diclofop; Herbicide resistance; Plant breeding
106                                                   NAL Call. No.: SB951.P49Evaluation of paraquat resistance mechanisms in Conyza.Norman, M.A.; Fuerst, E.P.; Smeda, R.J.; Vaughn, K.C.Orlando, Fla. : Academic Press; 1993 Jul.Pesticide biochemistry and physiology v. 46 (3): p. 236-249; 1993 Jul.Includes references.
Language:  English
Descriptors: Conyza bonariensis; Biotypes; Herbicide resistance;Susceptibility; Paraquat; Resistance mechanisms; Enzymes; Glutathionereductase (nad(p)h); Superoxide dismutase; Enzyme activity; Metabolicdetoxification; Photosystem i
Abstract:  Experiments were conducted to determine the mechanism(s) ofparaquat 1,1'-dimethyl-4, 4'-bipyridinium ion) resistance in a biotype ofhairy fleabane (Conyza bonariensis (L.) Cronq.). Thin-layer chromatographicanalysis of leaf extracts indicated that paraquat is not metabolized in eitherthe resistant (R) or the sensitive (S) biotype. Three in vitro studiesdemonstrated that electron transfer from the photosystem I (PSI) donor FA/FB)to paraquat is similar in both biotypes as was the amount and character of thetwo FA/FB iron-sulfur clusters. The relative activities of the stromal enzymessuperoxide dismutase, ascorbate peroxidase, and glutathione reductase, whichcan detoxify paraquat-generated noxious oxygen species, were determinedfollowing separation by polyacrylamide gel electrophoresis. Of these enzymes,only an increase in ascorbate peroxidase activity (28%) was observed instromal extracts of the R (relative to S) biotype. These data indicate thatthe 100-fold level of paraquat resistance observed in leaves of the R biotypeof Conyza is not due to metabolic detoxification, an altered insensitive) siteof action. and/or enhanced activities of stromal enzymes. Paraquat-inducedchlorosis (an indicator of sensitivity) was similar in illuminated chloroplastpreparations of both biotypes indicating that the resistance factor is locatedoutside of the chloroplast's envelope. Similar rates of paraquat-inducedchlorosis were also observed in illuminated protoplast preparations of bothbiotypes; however, leaf sections (1 mm width) of the R biotype exhibited adegree of paraquat resistance (81-fold) very similar to that exhibited bywhole leaves. These data suggest that resistance is due to a sequestrationmechanism that prevents paraquat from diffusing to PSI, the site of paraquataction. The sequestration mechanism appears to require a structurally intactcell wall to be functional.
107                                                   NAL Call. No.: QH301.A76Evaluation of post-emergence herbicides for forestry seedbeds.Clay, D.V.; Goodall, J.S.; Williamson, D.R.Wellesbourne, Warwick : The Association of Applied Biologists; 1992.Aspects of applied biology (29): p. 139-148; 1992.  In the series analytic:Vegetation management in forestry, amenity and conservation areas. Paperpresented at the conference of the Association, April 7-9, 1992, University ofYork, England.  Includes references.
Language:  English
Descriptors: England; Betula pendula; Larix leptolepis; Picea sitchensis;Alnus glutinosa; Forest nurseries; Seedbeds; Field experimentation; Herbicideresistance; Herbicides; Injuries; Phytotoxicity; Pot experimentation
108                                                      NAL Call. No.: SB1.H6Evaluations and correlated responses for resistance to chloramben herbicide incucumber.Staub, J.E.; Knerr, L.D.; Weston, L.A.Alexandria, Va. : American Society for Horticultural Science; 1991 Jul.HortScience v. 26 (7): p. 905-908; 1991 Jul.  Includes references.
Language:  English
Descriptors: Wisconsin; Cucumis sativus; Germplasm; Collections; Screening;Herbicide resistance; Chloramben; Crop damage; Phytotoxicity
Abstract:  The U.S. cucumber germplasm collection (753 accessions) and U.S.adapted processing cucumber (Cucumis sativus L.) inbreds and hybrids weresurveyed for response to 6.7 kg ae/ha of chloramben. Nine plant introductions(PI 165952, 173892, 179676, 275411, 277741, 279464, 279465, 436609, and482464) were classified as tolerant to chloramben, based on percentage andrate of field emergence and seedling vigor. All adapted strains evaluated weresusceptible to chloramben injury. The chloramben-tolerant accessions (C0) weresubjected to two cycles of recurrent half-sib family selection that resultedin 11 C2 families. These families, a susceptible adapted line (WI 2870), andthe resistant PI 436609 were evaluated in the field (6.7 kg ae/ha) andlaboratory (0.0, 0.01, and 0.0001 M) for response to chloramben challenge.Significant (P = 0.05) differences between families were observed forpercentage emergence and phytotoxicity ratings. Correlations between emergenceand phytotoxicity ratings at two dates were low (r2 = -0.32 and -0.05).Significant (P = 0.05) interfamily differences were also recorded forpercentage germination, hypocotyl length, primary root length, and number oflateral roots in the laboratory. Correlated responses between these growthvariables were high (r2 = 0.78 to 0.84), but correlations between field andlaboratory observations were low (r2 = - 0.31 to 0.24). We hypothesize thatthe genetic response to chloramben challenge under laboratory conditionsdepends on the concentration of the chemical administered. Chemical name used:3-amino-2, 5-dichlorobenzoic acid (chloramben).
109                                                   NAL Call. No.: QK710.P62Expression and stability of amplified genes encoding5-enolpyruvylshikimate-3-phosphate synthase in glyphosate-tolerant tobaccocells.Wang, Y.; Jones, J.D.; Weller, S.C.; Goldsbrough, P.B.Dordrecht : Kluwer Academic Publishers; 1991 Dec.Plant molecular biology : an international journal on molecular biology,biochemistry and genetic engineering v. 17 (6): p. 1127-1138; 1991 Dec.Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Genes; Ligases; Nucleotide sequences; Aminoacid sequences; Amplification; Glyphosate; Herbicide resistance; Geneexpression; Messenger  RNA; Cell lines; Regeneration
Abstract:  Two distinct cDNAs for 5-enolpyruvylshikimate-3-phosphate synthase(EPSPS) were obtained from a glyphosate-tolerant tobacco cell line. The cDNAswere 89% identical and the predicted sequences of the mature proteins weregreater than 83% identical with EPSPS proteins from other plants. TobaccoEPSPS proteins were more similar to those from tomato and petunia thanArabidopsis. One cDNA clone, EPSPS-1, represented a gene that was amplified inglyphosate-tolerant cells, while the gene for EPSPS-2 was unaltered in thesecells. Consequently, EPSPS-1 mRNA was more abundant in tolerant thanunselected cells, whereas EPSPS-2 mRNA was at relatively constant levels inthese cell lines. Exposure of unselected cells and tobacco leaves toglyphosate produced a transient increase in EPSPS mRNA. However,glyphosate-tolerant cells containing amplified copies of EPSPS genes did notshow a similar response following exposure to glyphosate. A significantproportion of the EPSPS gene amplification was maintained when tolerant cellswere grown in the absence of glyphosate for eight months. Plants regeneratedfrom these cells also contained amplified EPSPS genes.
110                                                    NAL Call. No.: 450 P692Expression of Erwinia uredovora phytoene desaturase in Synechococcus PCC7942leading to resistance against a bleaching herbicide.Windhovel, U.; Geiges, B.; Sandmann, G.; Boger, P.Rockville, MD : American Society of Plant Physiologists, 1926-; 1994 Jan.Plant physiology v. 104 (1): p. 119-125; 1994 Jan.  Includes references.
Language:  English
Descriptors: Synechococcus; Erwinia uredovora; Genetic transformation;Structural genes; Oxygenases; Recombinant  DNA; Promoters; Gene expression;Herbicide resistance; Norflurazon; Carotenoids; Biosynthesis; Phytoene
Abstract:  The gene coding for phytoene desaturase of the bacterium Erwiniauredovora (crtI) was inserted into the chromosome of the cyanobacteriumSynechococcus PCC7942 strain R2-PIM8. For expression of crtI in theheterologous host, two constructs with different promoters were introducedinto Synechococcus. In the first, crtI was fused to the 5' region of the psbAgene of the xanthophycean microalga Bumilleriopsis filiformis. The secondconstruct carried crtI inserted downstream of the neomycin phosphotransferaseII gene (nptII) from the transposon Tn5. Expression of crtI under the controlof the respective promoter was shown by immunodetection of the gene product.The functionality of the heterologously expressed phytoene desaturase CRTI inthe transformants was demonstrated by enzymic assays. The transformantsacquired very strong resistance toward the bleaching herbicide norflurazon.
111                                                   NAL Call. No.: 442.8 G28Expression of the maize MnSod (Sod3) gene in MnSOD-deficient yeast rescues themutant yeast under oxidative stress.Zhu, D.; Scandalios, J.G.Baltimore, Md. : Genetics Society of America; 1992 Aug.Genetics v. 131 (4): p. 803-809; 1992 Aug.  Includes references.
Language:  English
Descriptors: Zea mays; Saccharomyces cerevisiae; Structural genes; Superoxidedismutase; Manganese; Genetic transformation; Gene transfer; Gene expression;Mitochondria; Enzyme activity; Oxygen; Free radicals; Paraquat; Herbicideresistance; Stress; Mutants; Induced mutations; Complementation
Abstract:  Superoxide dismutases (SOD) are ubiquitous in aerobic organisms andare believed to play a significant role in protecting cells against the toxic,often lethal, effect of oxygen free radicals. However, direct evidence thatSOD does in fact participate in such a protective role is scant. TheMnSOD-deficient yeast strain (Sod2d) offered an opportunity to test thefunctional role of one of several SOD isozymes from the higher plant maize inhopes of establishing a functional bioassay for other SODs. Herein, we presentevidence that MnSOD functions to protect cells from oxidative stress and thatthis function is conserved between species. The maize Sod3 gene was introducedinto the yeast strain Sod2d where it was properly expressed and its productprocessed into the yeast mitochondrial matrix and assembled into thefunctional homotetramer. Most significantly, expression of the maize Sod3transgene in yeast rendered the transformed yeast cells resistant toparaquat-induced oxidative stress by complementing the MnSOD deficiency.Furthermore, analyses with various deletion mutants of the maize SOD-3 transitpeptide in the MnSOD-deficient yeast strain indicate that the initial portion(about 8 amino acids) of the maize transit peptide is required to direct theprotein into the yeast mitochondrial matrix in vivo to function properly.These findings indicate that the functional role of maize MnSOD is conservedand dependent on its proper subcellular location in the mitochondria of aheterologous system.
112                                                    NAL Call. No.: QH442.B5Fertile, transgenic oat plants.Somers, D.A.; Rines, H.W.; Gu, W.; Kaeppler, H.F.; Bushnell, W.R.New York, N.Y. : Nature Publishing Company; 1992 Dec.Bio/technology v. 10 (12): p. 1589-1594; 1992 Dec.  Includes references.
Language:  English
Descriptors: Avena sativa; Transgenics; Genetic transformation; Callus; Direct DNAuptake; Reporter genes; Beta-glucuronidase; Phosphotransferases;Glufosinate; Herbicide resistance; Regenerative ability; Fertility;Inheritance; Histoenzymology
113                                                   NAL Call. No.: 470 SCI24First gene-splice wheat.Washington, D.C. : Science Service :.; 1992 Jun06.Science news v. 141 (23): p. 379; 1992 Jun06.
Language:  English
Descriptors: Triticum aestivum; Genetic engineering; Herbicide resistance
114                                                   NAL Call. No.: SB610.W39Flurtamone for wild mustard (Sinapis arvensis) control in canola (Brassicanapus and B. campestris).Wall, D.A.Champaign, Ill. : The Weed Science Society of America; 1992 Oct.Weed technology : a journal of the Weed Science Society of America v. 6 (4):p. 878-883; 1992 Oct.  Includes references.
Language:  English
Descriptors: Canada; Cabt; Brassica napus; Brassica campestris; Cultivars;Herbicide resistance; Flurtamone; Application rates; Crop density; Crop yield;Sinapis arvensis; Weed control; Chemical control
115                                                     NAL Call. No.: SB1.J66Frequency of iron application influences bermudagrass tolerance to herbicides.Carrow, R.N.; Johnson, B.J.Washington, D.C. : Horticultural Research Institute; 1992 Dec.Journal of environmental horticulture v. 10 (4): p. 228-231; 1992 Dec.Includes references.
Language:  English
Descriptors: Cynodon dactylon; Cynodon; Hybrids; Iron fertilizers; Lawns andturf; Crop damage; Weed control; Chemical control; Herbicide resistance;Imazaquin; Metribuzin; Msma
116                                                    NAL Call. No.: 79.8 W41Fun with mutants: applying genetic methods to problems of weed physiology.Christianson, M.L.Champaign, Ill. : Weed Science Society of America; 1991 Jul.Weed science v. 39 (3): p. 489-496; 1991 Jul.  Paper presented at the"Symposium on New Techniques adn Advances in Weed Physiology and MolecularBiology," February 6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Weeds; Weed biology; Mutants; Herbicide resistance; Mode ofaction; Chlorsulfuron; Mutagens; Induced mutations; Mutagenesis; Pollen;Seeds; Screening; Selection criteria; Molecular genetics
Abstract:  Genetics can be a powerful adjunct to just about any kind ofphysiological study, including weed physiology or weed/herbicide interactions.Making, mapping, and reverting mutations is simple and straightforward. Makingmutants can be as simple as isolating variant individuals from the "wild", asuncomplicated as doing seed mutagenesis in your laboratory, or as sneaky asrecovering mutants as sectors in whole plants. The overall principles forsuccessful development of a protocol for seed mutagenesis of weeds aredescribed and potential problem areas noted. These generalities areillustrated with a specific case history, that of chlorsulfuron. Althoughchlorsulfuron is accurately described as an inhibitor of the synthesis ofbranched chain amino acids, careful physiological examination suggests that itkills plant cells, not by starvation for amino acids, but by active toxicityof a metabolite, alpha-amino butyric acid, produced from a precursor availablefor diversion in cells with inhibited acetolactate synthase (EC 4.1.3.18,ALS). The story of dominant resistance due to an altered ALS enzyme is wellknown; analysis using additional mutants fleshes out the story of howchlorsulfuron works. Such analysis has the potential to help unravel otherproblems in weed physiology.
117                                                   NAL Call. No.: QK710.P62Functional analysis of the two homologous psbA gene copies in SynechocystisPCC 6714 and PCC 6803.Bouyoub, A.; Vernotte, C.; Astier, C.Dordrecht : Kluwer Academic Publishers; 1993 Jan.Plant molecular biology : an international journal on molecular biology,biochemistry and genetic engineering v. 21 (2): p. 249-258; 1993 Jan.Includes references.
Language:  English
Descriptors: Cyanobacteria; Multiple genes; Structural genes; Proteins;Photosystem ii; Mutations; Herbicide resistance; Thylakoids; Photosynthesis;Gene mapping; Restriction mapping; Light intensity
Abstract:  The cyanobacteria Synechocystis 6803 and 6714 contain three genes(psbA) coding for the D1 protein. This protein is an essential subunit ofphotosystem II (PSII) and is the target for herbicides. We have usedherbicide-resistant mutants to study the role of the two homologous copies ofthe psbA genes in both strains (the third copy is not expressed). Severalherbicide resistance mutations map within the psbAI gene in Synechocystis 6714(G. Ajlani et al., Plant Mol. Biol. 13 (1989): 469-479). We have looked formutations in copy II. Results show that in Synechocystis 6714, only psbAIcontains herbicide resistance mutations. Relative expression of psbAI andpsbAII has been measured by analysing the proportions of resistant andsensitive D1 in the thylakoid membranes of the mutants. In normal growthconditions, 95% resistant D1 and 5% sensitive D1 were found. In high lightconditions, expression of psbAII was enhanced, producing 15% sensitive D1.This enhancement is specifically due to high light and not to the decrease ofD1 concentration caused by photoinhibition. Copy I of Synechocystis 6714corresponds to copy 2 of Synechocystis 6803 since it was always psbA2 whichwas recombined in Synechocystis 6803 transformants. PSII of the transformantstrains was found to be 95% resistant to herbicides as in resistant mutants ofSynechocystis 6714.
118                                                   NAL Call. No.: QK710.P68Functional expression of the Erwinia uredovora carotenoid biosynthesis genecrtl in transgenic plants showing an increase of beta-carotene biosynthesisactivity and resistance to the bleaching herbicide norflurazon.Misawa, N.; Yamano, S.; Linden, H.; Felipe, M.R. de; Lucas, M.; Ikenaga, H.;Sandmann, G.Oxford : Blackwell Scientific Publishers and BIOS Scientific Publishers inassociation with the Society for Experimental Biology, c1991-; 1993 Nov.The Plant journal : for cell and molecular biology v. 4 (5): p. 833-840; 1993Nov.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Transgenics; Biosynthesis; Carotenoids;Herbicide resistance; Norflurazon
119                                                   NAL Call. No.: SB610.W39Future impact of crops with modified herbicide resistance.Wyse, D.L.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 665-668; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Herbicide resistance; Biotechnology;Weed control; Development plans
120                                                  NAL Call. No.: QD341.A2N8Gene rescue in plants by direct gene transfer of total genomic DNA intoprotoplasts.Gallois, P.; Lindsey, K.; Malone, R.; Kreis, M.; Jones, M.G.K.Oxford : IRL Press; 1992 Aug11.Nucleic acids research v. 20 (15): p. 3977-3982; 1992 Aug11.  Includesreferences.
Language:  English
Descriptors: Nicotiana tabacum; Arabidopsis thaliana; Beta vulgaris; Genetransfer; Protoplasts; Genes; Isolation; Mutants; Herbicide resistance;Chlorsulfuron; In vitro selection; Electroporation; Genetic transformation;Plasmids; Kanamycin; Drug resistance; Direct  DNAuptake; Transgenic plants;Segregation
Abstract:  To study the possibility of gene rescue in plants by direct genetransfer we chose the Arabidopsis mutant GH50 as a source of donor DNA. GH50is tolerant of chlorsulfuron, a herbicide of the sulfonylurea class. Tobaccoprotoplasts were cotransfected with genomic DNA and the plasmid pHP23 whichconfers kanamycin resistance. A high frequency of cointegration of the plasmidand the genomic DNA was expected, which would allow the tagging of the plantselectable trait with the plasmid DNA. After transfection by electroporationthe protoplasts were cultivated on regeneration medium supplemented witheither chlorsulfuron or kanamycin as a selective agent. Selection on kanamycinyielded resistant calluses at an absolute transformation frequency (ATF) of0.8 X 10(-3). Selection on chlorsulfuron yielded resistant calluses at an ATFof 4.7 X 10(-6). When a selection on chlorsulfuron was subsequently applied tothe kanamycin resistant calluses, 8% of them showed resistance to thisherbicide. Southern analysis carried out on the herbicide resistanttransformants detected the presence of the herbicide resistance gene ofArabidopsis into the genome of the transformed tobacco. Segregation analysisshowed the presence of the resistance gene and the marker gene in the progenyof the five analysed transformants. 3 transformants showed evidence of geneticlinkage between the two genes. In addition we show that using the sametechnique a kanamycine resistance gene from a transgenic tobacco could betransferred into sugar beet protoplasts at a frequency of 0.17% of thetransformants.
121                                                   NAL Call. No.: 442.8 Z34Gene SNQ2 of Saccharomyces cerevisiae, which confers resistance to4-nitroquinoline-N-oxide and other chemicals, encodes a 169 kDa proteinhomologous to ATP-dependent permeases.Servos, J.; Haase, E.; Brendel, M.Berlin, W. Ger. : Springer International; 1993 Jan.M G G : Molecular and general genetics v. 236 (2/3): p. 214-218; 1993 Jan.The accession number 66732 does not conform to standard format.  Includesreferences.
Language:  English
Descriptors: Saccharomyces cerevisiae; Structural genes; Plant proteins;Resistance; Mutagens; Quinolines; Aromatic compounds; Sulfometuron; Herbicideresistance; Nucleotide sequences; Amino acid sequences; Gene expression; Atp;Binding site
Abstract:  The yeast gene SNQ2 confers hyper-resistance to the mutagens4-nitroquinoline-N-oxide (4-NQO) and Triaziquone, as well as to the chemicalssulphomethuron methyl and phenanthroline when present in multiple copies intransformants of Saccharomyces cerevisiae. Subcloning and sequencing of a 5.5kb yeast DNA fragment revealed that SNQ2 has an open reading frame of 4.5 kb.The putative encoded polypeptide of 1501 amino acids has a predicted molecularweight of 169 kDa and has several hydrophobic regions. Northern analysisshowed a transcript of 5.5 kb. Haploid cells with a disrupted SNQ2 readingframe are viable. The SNQ2-encoded protein has domains believed to be involvedin ATP binding and is likely to be membrane associated. It most probablyserves as an ATP-dependent permease.
122                                                   NAL Call. No.: TA166.T72Genes of jeans: biotechnological advances in cotton.John, M.E.; Stewart, J.M.New York, N.Y. : Elsevier Science Publishing Co; 1992 May.Trends in biotechnology v. 10 (5): p. 165-170; 1992 May.  Includes references.
Language:  English
Descriptors: Gossypium; Biotechnology; Genetic engineering; Selectioncriteria; Agronomic characteristics; Crop management; Improvement; Fiberquality; Modification; Genes
Abstract:  Cotton is a crop of global economic importance. The impact ofadvances in cotton genetic engineering will therefore go beyond just alteringthe patterns of agronomic practice to have a major effect on both economic andsocial structures. Although the majority of characteristics currently beingengineered into cotton (i.e. insect- and herbicide-tolerance) relate toimproved crop management, the longer-term goals of modifying fiber are toimprove and develop novel properties for the product.
123                                                   NAL Call. No.: 442.8 G28Genetic interactions among Chlamydomonas reinhardtii mutations that conferresistance to anti-microtubule herbicides.James, S.W.; Lefebvre, P.A.Baltimore, Md. : Genetics Society of America; 1992 Feb.Genetics v. 130 (2): p. 305-314; 1992 Feb.  Includes references.
Language:  English
Descriptors: Chlamydomonas reinhardtii; Loci; Recessive genes; Alleles;Mutations; Herbicide resistance; Amiprofos-methyl; Oryzalin; Microtubules;Complementation; Gene interaction; Flagella; Deuterium oxide; Genetic change
Abstract:  We previously described two types of genetic interactions amongrecessive mutations in the APM1 and APM2 loci of Chlamydomonas reinhardtiithat may reflect a physical association of the gene products or theirinvolvement in a common structure/process: (1) allele-specific syntheticlethality, and (2) unlinked noncomplementation, or dominant enhancement. Tofurther investigate these interactions, we isolated revertants in which theheat sensitivity caused by the apm2-1 mutation is lost. The heat-insensitiverevertants were either fully or partially suppressed for the drug-resistancecaused by the apm2-1 allele, In recombination tests the revertants behaved asif the suppressing mutation mapped within the APM2 locus; the partialsuppressors of apm2-1 herbicide resistance failed to complement apm2-1,leading to the conclusion that they were likely to be intragenicpseudorevertants. The apm2-1 partial suppressor mutations reversed apm1-apm2-1synthetic lethality in an allele-specific manner with respect both to apm1-alleles and apm2-1 suppressor mutations. Those apm1- apm2-1rev strains thatregained viability also regained heat sensitivity characteristic of theoriginal apm2-1 mutation, even though the apm2-1 suppressor strains were fullyheat-insensitive. The Hs+ phenotypes of apm2-1 partial suppressors were alsoreversed by treatment with the microtubule-stabilizing agent deuterium oxide(D2O). In addition to the above interactions, we observed interalleliccomplementation and phenotypic enhancement of temperature conditionality amongapm1- alleles. Evidence of a role for the products of the two genes inmicrotubule-based processes was obtained from studying flagellar assembly inapm1- and apm2- mutants.
124                                                   NAL Call. No.: 442.8 G28Genetic interactions at the FLA10 locus: suppressors and synthetic phenotypesthat affect the cell cycle and flagellar function in Chlamydomonasreinhardtii.Lax, F.G. III; Dutcher, S.K.Baltimore, Md. : Genetics Society of America; 1991 Jul.Genetics v. 128 (3): p. 549-561; 1991 Jul.  Includes references.
Language:  English
Descriptors: Chlamydomonas reinhardtii; Induced mutations; Mutants; Loci; Geneinteraction; Flagella; Motility; Temperature; Inhibitor genes; Cell division;Phenotypes; Herbicide resistance; Amiprofos-methyl; Oryzalin; Alleles
Abstract:  Through the isolation of suppressors of temperature-sensitiveflagellar assembly mutations at the FLA10 locus of Chlamydomonas reinhardtii,we have identified six other genes involved in flagellar assembly. Mutationsat these suppressor loci, termed SUF1-SUF6, display allele specificity withrespect to which fla10- mutant alleles they suppress. An additional mutation,apm1-122, which confers resistance to the plant herbicides amiprophos-methyland oryzalin, was also found to interact with mutations at the FLA10 locus.The apm1-122 mutation in combination with three fla10- mutant alleles resultsin synthetic cold-sensitive cell division defects, and in combination with anadditional pseudo-wild-type fla10- allele yields a synthetictemperature-sensitive flagellar motility phenotype. Based upon the geneticinteractions of these loci, we propose that the FLA10 gene product interactswith multiple components of the flagellar apparatus and plays a role both inflagellar assembly and in the cell cycle.
125                                                   NAL Call. No.: QH442.J69Genetic manipulation of crop plants.Lindsey, K.Amsterdam : Elsevier Science Publishers B.V.; 1992 Oct.Journal of Biotechnology v. 26 (1): p. 1-28; 1992 Oct.  In the special issue:Plant cell culture / edited by A.H. Scragg.  Literature review.  Includesreferences.
Language:  English
Descriptors: Crops; Genetic engineering; Genetic transformation; Geneticresistance; Plant development; Herbicide resistance; Literature reviews; Pestresistance
126                                                   NAL Call. No.: 442.8 Z34Genetic study and further biochemical characterization of a tobacco mutantthat overproduces sterols.Maillot-Vernier, P.; Gondet, L.; Schaller, H.; Benveniste, P.; Belliard, G.Berlin, W. Ger. : Springer International; 1991 Dec.M G G : Molecular and general genetics v. 231 (1): p. 33-40; 1991 Dec.Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Mutants; Mutations; Dominance; Segregation;Phytosterols; Sterol esters; Lipogenesis; Lipids; Droplets; Cytoplasm;Herbicide resistance; Triazole herbicides; Callus
Abstract:  A genetic and biochemical characterization is presented of atobacco mutant that was previously shown to have an increased sterol contentwith an accumulation of biosynthetic intermediates. We first show that aprecise regulation of the membrane sterol composition occurs in this mutant,via a selective esterification process. Indeed, sterols representing the usualend-products of the biosynthetic pathway are preferably integrated into themembranes as free sterols, whereas most of the intermediates pool isesterified and stored in cytoplasmic lipid droplets. It is furtherdemonstrated that overproduction of sterols by the LAB1-4 mutant is due to asingle nuclear and semi-dominant mutation. Finally, increase of biosynthesisand esterification of unusual sterols are shown to be responsible for theresistance of LAB1-4 calli to LAB170 250F, the triazole pesticide used toselect this mutant. However, differentiated LAB1-4 tissues do not express theresistance trait, suggesting that sterol biosynthesis might not be the onlysite of action for the triazole at the plant level.
127                                                     NAL Call. No.: 472 N42Genetic weeding and feeding for tobacco plants.Bradley, D.London, Eng. : New Science Publications; 1992 Jan04.New scientist v. 133 (1802): p. 11; 1992 Jan04.
Language:  English
Descriptors: Nicotiana tabacum; Myrothecium verrucaria; Genetic engineering;Herbicide resistance
128                                                   NAL Call. No.: 61.8 SE52Genetically altered seed & how it will be distributed.Grooms, L.Des Plains, Ill. : Scranton Gillette Communications, Inc; 1992 Nov.Seed world v. 130 (12): p. 8-9, 11-13; 1992 Nov.
Language:  English
Descriptors: Seeds; Genetic engineering; Distribution; Herbicide resistance;Pest resistance
129                                             NAL Call. No.: S494.5.B563B554Genetically engineered plants for herbicide resistance.Mullineaux, P.M.Wallingford, Oxford, UK : CAB International; 1992.Biotechnology in agriculture v. 7: p. 75-107; 1992.  In the series analytic:Plant genetic manipulation for crop protection / edited by A.M.R. Gatehouse,V.A. Hilder and Boulter, D.  Includes references.
Language:  English
Descriptors: Crops; Herbicides; Herbicide resistance; Gene expression; Geneticengineering; Genetic transformation; Vectors; Biochemical pathways; Amino acidmetabolism; Protein synthesis; Enzyme activity; Genes; Amplification;Structure activity relationships; Detoxification; Glutathione transferase;Herbicide safeners; Chimerism; Plant protection; Amino acid sequences;Mutations
130                                             NAL Call. No.: S494.5.B563A382Genetically-engineered herbicide-resistant crops--a moral imperative for worldfood production.Gressel, J.Milan, Italy : Teknoscienze,; 1992 Nov.Agrofoodindustry hi-tech v. 3 (6): p. 3-7; 1992 Nov.  Includes references.
Language:  English
Descriptors: Crops; Herbicide resistance; Genetic engineering; Weed control;Herbicides
131                                                   NAL Call. No.: 442.8 Z34Glyphosate selected amplification of the 5-enolpyruvylshikimate-3-phosphatesynthase gene in cultured carrot cells.Shyr, Y.Y.J.; Hepburn, A.G.; Widholm, J.M.Berlin, W. Ger. : Springer International; 1992 Apr.M G G : Molecular and general genetics v. 232 (3): p. 377-382; 1992 Apr.Includes references.
Language:  English
Descriptors: Daucus carota; Structural genes; Transferases; In vitroselection; Glyphosate; Herbicide resistance; Amplification; Gene expression;Messenger  RNA; Gene dosage; Tissue culture; Cell suspensions
Abstract:  CAR and C1, two carrot (Dacus carota L.) suspension cultures ofdifferent genotypes, were subjected to stepwise selection for tolerance to theherbicide glyphosate [(N-phosphonomethyl)glycine]. The specific activity ofthe target enzyme, 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), aswell as the mRNA level and copy number of the structural gene increased witheach glyphosate selection step. Therefore, the tolerance to glyphosate is dueto stepwise amplification of the EPSPS genes. During the amplificationprocess, DNA rearrangement did not occur within the EPSPS gene of the CAR cellline but did occur during the selection step from 28 to 35 mM glyphosate forthe C1 cell line, as determined by Southern hybridization of selected cell DNAfollowing EcoRI restriction endonuclease digestion. Two cell lines derivedfrom a previously selected glyphosate-tolerant cell line (PR), which also hadundergone EPSPS gene amplification but have been maintained in glyphosate-freemedium for 2 and 5 years, have lost 36 and 100% of the increased EPSPSactivity, respectively. Southern blot analysis of these lines confirms thatthe amplified DNA is relatively stable in the absence of selection. Thesestudies demonstrate that stepwise selection for glyphosate resistancereproducibly produces stepwise amplification of the EPSPS genes. The relativestability of this amplification indicates that the amplified genes are notextrachromosomal.
132                                                   NAL Call. No.: QK710.P62Glyphosate tolerance of cultured Corydalis sempervirens cell is acquired by anincreased rate of transcription of 5-enolpyruvylshikimate 3-phosphate synthaseas well as by a reduced turnover of the enzyme.Hollander-Czytko, H.; Sommer, I.; Amrheim, N.Dordrecht : Kluwer Academic Publishers; 1992 Dec.Plant molecular biology : an international journal on molecular biology,biochemistry and genetic engineering v. 20 (6): p. 1029-1036; 1992 Dec.Includes references.
Language:  English
Descriptors: Corydalis; Transcription; Gene expression; Ligases; Glyphosate;Herbicide resistance; Messenger  RNA; Enzyme activity; Genetic regulation;Cell culture
Abstract:  Cell cultures of Corydalis sempervirens, tolerant to the herbicideglyphosate, have a 30-40-fold increased level of the herbicide's target enzyme5-enolpyruvylshikimate 3-phosphate (EPSP) synthase, a ten-fold enhanced levelof the corresponding mRNA but no amplification of the gene (Hollander-Czytkoet al., Plant Mol Biol 11 (1988) 215-220). The increase at the transcriptionallevel is due to a higher rate of transcription of the gene, which was observedin run-off transcription assays with isolated nuclei. The furtheramplification at the protein level is the result of stabilization of theenzyme by the herbicide. In the presence of glyphosate the half-life of EPSPsynthase was doubled leading to higher levels of both protein and enzymeactivity. Overproduction of the enzyme in adapted cultures is stable at thetranscriptional level, as cells from adapted cultures grown in the absence ofglyphosate for three years still display an about ten-fold higher enzymeactivity and transcript level than non-adapted cultures.
133                                                 NAL Call. No.: SB610.2.B74Glyphosate-tolerant crops for the future: development, risks and benefits.Waters, S.Surrey : BCPC Registered Office; 1991.Brighton Crop Protection Conference-Weeds v. 1: p. 165-170; 1991.  Includesreferences.
Language:  English
Descriptors: Crops; Weed control; Herbicide resistance; Tolerance; Glyphosate
134                                                   NAL Call. No.: SB951.P49Graminicide resistance of acetyl-CoA carboxylase from ornamental grasses.Catanzaro, C.J.; Burton, J.D.; Skroch, W.A.Orlando, Fla. : Academic Press; 1993 Feb.Pesticide biochemistry and physiology v. 45 (2): p. 147-153; 1993 Feb.Includes references.
Language:  English
Descriptors: Festuca ovina; Festuca; Cultivars; Erianthus; Pennisetumalopecuroides; Panicum virgatum; Sethoxydim; Fluazifop; Herbicide resistance;Susceptibility; Acetyl-coa carboxylase; Enzyme activity; Atp; Weed control
Abstract:  Blue fescues [Festuca ovina var. glauca (Lam.) Koch. and F.amethystina L.] are resistant to graminicides, whereas fountain grass[Pennisetum alopecuroides (L.) Spreng.] and most other grasses are sensitive.Evidence suggests that selective control of grasses by the graminicidesfluazifop (an aryloxyphenoxypropionate) and sethoxydim (a cyclohexanedione) isoften due to differential resistance at the primary site of action, acetyl-CoAcarboxylase (ACCase). ACCase activity was obtained from fountain grass andfour cultivars of blue fescue to determine whether resistance at the wholeplant level correlated with ACCase resistance in vitro. ACCase activity wasrepresented by in vitro incorporation of radioactive bicarbonate into an acidand heat-stable product. Enzyme activity was dependent on acetyl-CoA and ATPand was inhibited in the presence of avidin, suggesting that activity was dueto ACCase. Compared to ACCase from fountain grass, ACCase from fescues was 70to 88 times more resistant to fluazifop and 216 to 422 times more resistant tosethoxydim. Differences of this magnitude at the enzyme level may besufficient to explain differential response between blue fescues (resistant)and fountain grass (sensitive) at the whole plant level.
135                                                   NAL Call. No.: 79.9 W52RGrass tolerance to imazethapyr.Ferrell, M.A.; Koch, D.W.; Ogg, P.J.; Hruby, F.S.l. : The Society; 1992.Research progress report - Western Society of Weed Science. p. III/97-III/98;1992.  Meeting held on March 9-12, 1992, Salt Lake City, Utah.
Language:  English
Descriptors: Wyoming; Grasses; Herbicide resistance; Imazethapyr
136                                                    NAL Call. No.: 79.8 W41Growth response of wheat (Triticum aestivum) callus to imazapyr and in vitroselection for resistance.Heering, D.C.; Guenzi, A.C.; Peeper, T.F.; Claypool, P.L.Champaign, Ill. : Weed Science Society of America; 1992 Apr.Weed science v. 40 (2): p. 174-179; 1992 Apr.  Includes references.
Language:  English
Descriptors: Triticum aestivum; Herbicide resistance; Mutations; Callus; Invitro selection; Imazapyr; Application rates; Growth rate; Isoleucine;Leucine; Valine; Amino acid metabolism; Enzyme inhibitors
Abstract:  Intact wheat plants and wheat calli responded similarly to varyingconcentrations of imazapyr. Fifty percent growth inhibition of wheat callusoccurred with 0.05 micromolar imazapyr after 70 d. As imazapyr concentrationincreased from 0 to 10 micromolar, the free isoleucine, leucine, and valinedecreased from 160 to 35, 260 to 49, and 310 to 59 pmol mg-1, respectively.Resistant calli, which had relative growth rates exceeding a calculated upperprediction interval, were obtained by in vitro selection at 2 and 5 micromolarimazapyr. Resistant calli growing on 2 micromolar imazapyr had freeisoleucine, leucine, and valine concentrations intermediate to the control andsusceptible callus.
137                                                     NAL Call. No.: 450 AN7Haploid culture and UV mutagenesis in rapid-cycling Brassica napus for thegeneration of resistance to chlorsulfuron and Alternaria brassicola.Ahmad, I.; Day, J.P.; MacDonald, M.V.; Ingram, D.S.London : Academic Press; 1991 Jun.Annals of botany v. 67 (6): p. 521-525; 1991 Jun.  Includes references.
Language:  English
Descriptors: Brassica napus; Plant breeding; Selection; Haploids; Mutagenesis;Ultraviolet radiation; Chlorsulfuron; Herbicide resistance; Alternariabrassicicola; Plant pathogenic fungi; Disease resistance
Abstract:  The effect of ultra violet (UV) irradiation on cultured isolatedmicrospores of rapid cycling Brassica napus was investigated. The microsporeswere highly sensitive to UV, with the calculated LD50 being an exposure of 20s. Viability tests suggested that death of the microspores was not immediate,but occurred during subsequent incubation (7 d). None of the embryos producedfollowing UV-irradiation of microspores showed gross morphological variation.A large number of regenerants was established from embryoids and grown toflowering. These plants set fertile seed after selfing. The progenies wereassessed for resistance to Alternaria brassicicola and a small number showedincreased resistance to the pathogen, suggesting the generation of novelheritable resistance to this pathogen. In vitro selection revealed heritableresistance to the herbicide 'Glean' (active ingredient chlorsulfuron).
138                                                  NAL Call. No.: 284.28 W15Hardy crops yield herbicide controversy.Nazario, S.L.New York, N.Y. : Dow Jones; 1991 Aug01.The Wall Street journal. p. B1, B4; 1991 Aug01.
Language:  English
Descriptors: U.S.A.; Herbicide resistance; Genetic engineering; Bromoxynil;Environmental impact
139                                                     NAL Call. No.: 450 C16Harovinton soybean.Buzzell, R.I.; Anderson, T.R.; Hamill, A.S.; Welacky, T.W.Ottawa : Agricultural Institute of Canada; 1991 Apr.Canadian journal of plant science; Revue canadienne de phytotechnie v. 71 (2):p. 525-526; 1991 Apr.  Includes references.
Language:  English
Descriptors: Ontario; Glycine max; Cultivars; Protein content; Tofu; Diseaseresistance; Phytophthora megasperma; Herbicide resistance; Metribuzin
140                                                     NAL Call. No.: S544.N6Herbicide mode of action and injury symptoms.Gunsolus, J.L.; Curran, W.S.East Lansing, Mich. : The Service; 1992.North Central regional extension publication, Cooperative Extension Servicev.): 17 p.; 1992.
Language:  English
Descriptors: Herbicides; Mode of action; Application methods; Herbicideresistant weeds; Phototoxicity; Injuries; Symptoms
141                                             NAL Call. No.: S494.5.B563A382Herbicide resistance.Howard, J.; Baszczynski, C.Milan, Italy : Teknoscienze; 1992 Sep.Agrofoodindustry hi-tech v. 3 (5): p. 3-6; 1992 Sep.  Includes references.
Language:  English
Descriptors: Crops; Herbicide resistance; Biotechnology; Uses; Applications
142                                                     NAL Call. No.: S79.E37Herbicide resistance confirmed in johnsongrass biotypes.Barrentine, W.L.; Snipes, C.E.; Smeda, R.J.Mississippi State, Miss. : The Station; 1992 Aug.Research report - Mississippi Agricultural and Forestry Experiment Station v.17 (5): 5 p.; 1992 Aug.  Includes references.
Language:  English
Descriptors: Mississippi; Sorghum halepense; Herbicide resistant weeds;Biotypes; Herbicides; Weed control; Trails
143                                           NAL Call. No.: S397.M57 no.93/10Herbicide resistance coordination and communication in Western Australia.Martin, R. J.Western Australia : Dept. of Agriculture,; 1993.17 p. : ill., map ; 30 cm. (Miscellaneous publication (Western Australia.Dept. of Agriculture) ; no. 93/10.).  Cover title.  March 17, 1993.  Agdex640.
Language:  English
144                                                   NAL Call. No.: 442.8 Z34Herbicide resistance due to amplification of a mutant acetohydroxyacidsynthase gene.Harms, C.T.; Armour, S.L.; DiMaio, J.J.; Middlesteadt, L.A.; Murray, D.;Negrotto, D.V.; Thompson-Taylor, H.; Weymann, K.; Montoya, A.L.; Shillito,R.D.; Jen, G.C.Berlin, W. Ger. : Springer International; 1992 Jun.M G G : Molecular and general genetics v. 233 (3): p. 427-435; 1992 Jun.Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Amplification; Structural genes; Multiplegenes; Oxo-acid-lyases; Herbicide resistance; Sulfonylurea herbicides;Imazaquin; In vitro selection; Enzyme activity; Mutants; Mutations; Genetictransformation; Transgenics; Protoplasts; Cell suspensions
Abstract:  We have selected a tobacco cell line, SU-27D5, that is highlyresistant to sulfonylurea and imidazolinone herbicides. This line wasdeveloped by selection first on a lethal concentration of cinosulfuron andthen on increasing concentrations of primisulfuron, both sulfonylureaherbicides. SU-27D5 was tested against five sulfonylureas and oneimidazolinone herbicide and was shown, in every case, to be two to threeorders of magnitude more resistant than wild-type cells. The acetohydroxyacidsynthase (AHAS) of SU-27D5 was 50- to 780-fold less sensitive than that ofwild-type cells to herbicide inhibition. The specific activity of AHAS in theSU-27D5 cell lysate was 6 to 7 times greater than that in wild-type cells.Using Southern analysis, we showed that cell line SU-27D5 had amplified itsSuRB AHAS gene about 20-fold while maintaining a normal diploid complement ofthe SuRA AHAS gene. Genomic clones of both AHAS genes were isolated and usedto transform wild-type tobacco protoplasts. SuRB clones gave rise toherbicide-resistant transformants, whereas SuRA clones did not. DNA sequencingshowed that all SuRB clones contained a point mutation at nucleotide 588 thatconverted amino acid 196 of AHAS from proline to serine. In contrast, nomutations were found in the SuRA clones. The stability of SuRB geneamplification was variable in the absence of selection. In one experiment, thewithdrawal of selection reduced the copy number of the amplified SuRB gene tothe normal level within 30 days. In another experiment, amplification remainedstable after extended cultivation on herbicide-free medium. This is the firstreport of amplification of a mutant herbicide target gene that resulted inbroad and strong herbicide resistance.
145                                                    NAL Call. No.: 450 P692Herbicide resistance in Datura innoxia. Kinetic characterization ofacetolactate synthase from wild-type and sulfonylurea-resistant cell variants.Rathinasabapathi, B.; King, J.Rockville, Md. : American Society of Plant Physiologists; 1991 May.Plant physiology v. 96 (1): p. 255-261; 1991 May.  Includes references.
Language:  English
Descriptors: Datura fastuosa; Cell cultures; Mutants; Sulfonylurea herbicides;Herbicide resistance; Imidazolinone herbicides; Ligases; Genetic variation;Cross resistance; Binding site; Amino acids; Biosynthesis
Abstract:  Acetolactate synthase (ALS, EC 4.1.3.18), the first enzyme in thebiosynthesis of branched-chain amino acids, was isolated from wild-type andsulfonylurea-resistant Datura innoxia cell variants and characterized.Apparent Km values of the ALS for pyruvate from three sulfonylurea-resistantvariants (CSR2, CSR6, and CSR10) were manyfold greater than that of the wildtype. The inhibition of wild-type and herbicide-resistant ALS activity bychlorsulfuron (CS), a sulfonylurea herbicide, and L-leucine (L-Leu), one ofthe feedback inhibitors of the enzyme, was examined. ALS from two CS-resistantvariants exhibited severalfold greater resistance to CS than did the wild-typeenzyme. Inhibition of ALS by L-Leu fitted a partially competitive pattern mostclosely. It is proposed that the herbicide resistance mutation accentuated thepartial inhibition characteristics of ALS by L-Leu. ALS from one of the twoCS-resistant variants (CSR6) had a Ki for L-Leu an order of magnitude greaterthan that of the wild-type enzyme. The alterations in kinetic propertiesobserved in the ALS from sulfonylurea-resistant variants are discussed inrelation to the possible evolutionary significance of the herbicide bindingsite of this enzyme, the physiological effects of such biochemicalalterations, and their practical utility in genetic studies.
146                                                   NAL Call. No.: SB951.P49Herbicide resistance in Setaria viridis conferred by a less sensitive form ofacetyl coenzyme A carboxylase.Marles, M.A.S.; Devine, M.D.; Hall, J.C.Orlando, Fla. : Academic Press; 1993 May.Pesticide biochemistry and physiology v. 46 (1): p. 7-14; 1993 May.  Includesreferences.
Language:  English
Descriptors: Manitoba; Setaria viridis; Biotypes; Herbicide resistance;Susceptibility; Aryloxyphenoxypropionic herbicides; Cyclohexene oximeherbicides; Mode of action; Uptake; Metabolism; Acetyl-coa carboxylase; Enzymeactivity; Inhibition
Abstract:  The mechanism of resistance was investigated in a biotype ofSetaria viridis resistant to aryloxyphenoxypropanoate and cyclohexanedioneherbicides. Uptake of fenoxaprop-ethyl and diclofop-methyl was equal in theresistant and susceptible biotypes. In addition, metabolism of these twoherbicides was similar in the resistant and susceptible biotypes, indicatingthat resistance is not based on altered herbicide metabolism. Fenoxaprop,diclofop, quizalofop, clethodim, sethoxydim, and tralkoxydim inhibitedacetyl-coenzyme A carboxylase (ACCase) extracted from the susceptible biotype,with I(50) values ranging from 0.078 to 1.7 micromolar. ACCase from theresistant biotype was much less sensitive to all herbicides, with I(50) values31 to 60 times higher than for the susceptible biotype. These results indicatethat herbicide resistance in this S. viridis biotype is conferred by analtered form of ACCase that is much less sensitive to a wide range ofaryloxyphenoxypropanoate and cyclohexanedione herbicides.
147                                           NAL Call. No.: SB951.4.H443 1991Herbicide resistance in weeds and crops.Caseley, J. C.; Cussans, G. W.; Atkin, R. K.Long Ashton International Symposium 11th : 1989.Oxford ; Boston : Butterworth-Heinemann,; 1991.xii, 513 p. : ill. ; 24 cm.  "Papers and poster abstracts presented at theEleventh Long Ashton International Symposium in September 1989"--Pref.Includes bibliographical references and index.
Language:  English
Descriptors: Herbicide resistance; Herbicide-resistant crops
148                                                   NAL Call. No.: QH540.A55Herbicide resistance in weedy plants: physiology and population biology.Warwick, S.I.Palo Alto, Calif. : Annual Reviews, Inc; 1991.Annual review of ecology and systematics v. 22: p. 95-114; 1991.  Literaturereview.  Includes references.
Language:  English
Descriptors: Weeds; Herbicide resistant weeds; Herbicide resistance; Geneflow; Genetic variation; Selection pressure; Natural selection; Triazines;Metabolic detoxification; Plant ecology; Reviews
149                                               NAL Call. No.: 275.29 M68ExtHerbicide resistance: prevention and detection.Byrd, J.D. Jr; Barrentine, W.L.; Shaw, D.R.State College, Miss. : Cooperative Extension Service, Mississippi StateUniversity; 1993 Sep.Publication / (1907): 4 p.; 1993 Sep.
Language:  English
Descriptors: Mississippi; Cabt; Crops; Weed control; Herbicides; Herbicideresistance; Susceptibility; Mode of action
150                                             NAL Call. No.: SB950.9.C44 v.7Herbicide resistance--brassinosteroids, gibberellins, plant growth regulators.Adam, G.Berlin ; New York : Springer-Verlag,; 1991.176 p. : ill. ; 24 cm. (Chemistry of plant protection ; 7).  Includesbibliographical references and index.
Language:  English
Descriptors: Herbicide resistance; Gibberellins; Brassinolide; Plantregulators
151                                                   NAL Call. No.: aZ5071.N3Herbicide resistance--January 1989-March 1991.Schneider, K.Beltsville, Md. : The Library; 1991 May.Quick bibliography series - U.S. Department of Agriculture, NationalAgricultural Library (U.S.). (91-104): 41 p.; 1991 May.  Updates QB 86-51.Bibliography.
Language:  English
Descriptors: Herbicide resistance; Bibliographies
152                                                    NAL Call. No.: QH442.B5Herbicide resistant fertile transgenic wheat plants obtained bymicroprojectile bombardment of regenerable embryogenic callus.Vasil, V.; Castillo, A.M.; Fromm, M.E.; Vasil, I.K.New York, N.Y. : Nature Publishing Company; 1992 Jun.Bio/technology v. 10 (6): p. 662-674; 1992 Jun.  Includes references.
Language:  English
Descriptors: Triticum aestivum; Genetic transformation; Direct  DNAuptake;Transgenics; Gene transfer; Structural genes; Acyltransferases; Plasmids;Herbicide resistance; Glufosinate; Callus; Regenerative ability;Embryogenesis; Reporter genes
153                                                   NAL Call. No.: 79.9 C122Herbicide resistant in weeds current status and future perspectives.Saari, L.L.Fremont, Calif. : California Weed Conference; 1991.Proceedings - California Weed Conference (43rd): p. 37-40; 1991.  Meeting heldJanuary 21-23, 1991, Santa Barbara, California.  Includes references.
Language:  English
Descriptors: Herbicide resistant weeds; Weed control; Chemical control
154                                                   NAL Call. No.: 443.8 H42Herbicide response polymorphism in wild populations of emmer wheat.Snape, J.W.; Nevo, E.; Parker, B.B.; Leckie, D.; Morgunov, A.Oxford : Blackwell Scientific Publications; 1991 Apr.Heredity v. 66 (pt.2): p. 251-257; 1991 Apr.  Includes references.
Language:  English
Descriptors: Israel; Triticum dicoccoides; Genes; Genetic resources;Evolution; Herbicide resistance; Difenzoquat; Metoxuron; Genetic polymorphism;Geographical distribution; Wild plants
Abstract:  The responses of wild populations of emmer wheat (Triticumdicoccoides), from different ecogeographical areas of Israel, to threeherbicides, difenzoquat, chlortoluron and metoxuron, commonly used oncultivated wheats, were studied. Although cultivated wheats are polymorphicfor a response to difenzoquat, all families of all populations of the wildspecies were resistant. The species was, however, polymorphic for response toboth chlortoluron and metoxuron. In addition, there appeared to bedifferentiation between populations in the frequencies of resistant andsusceptible morphs for these herbicides. There was also a close correspondencebetween the responses of individual families to chlortoluron and metoxuron,which suggests a common genetic control. The implications of these findingsfor understanding the evolution of herbicide resistance, and for developingstrategies for breeding for resistance in the cultivated species arediscussed.
155                                                    NAL Call. No.: 442.8 Z8Herbicide response polymorphisms in wild emmer wheat: ecological and isozymecorrelations.Nevo, E.; Snape, J.W.; Lavie, B.; Beiles, A.Berlin, W. Ger. : Springer International; 1992.Theoretical and applied genetics v. 84 (1/2): p. 209-216; 1992.  Includesreferences.
Language:  English
Descriptors: Israel; Triticum dicoccoides; Genetic resources; Herbicideresistance; Polymorphism; Metoxuron; Chlorotoluron; Phenotypes; Marker genes;Genotypes; Isoenzymes; Alloenzymes; Enzyme polymorphism; Genetic markers;Ecotypes; Geographical distribution; Gene frequency; Photosynthesis; Plantecology
Abstract:  We demonstrate that the scores and frequencies of chlortoluron (CT)and metoxuron (MX) resistance and susceptible phenotypes of wild emmer wheat,Triticum dicoccoides, are correlated with ecological factors and allozymemarkers. Some isozyme markers located on chromosome 6B (e.g. Adh, Est-4 andGot), which also harbours the CT and MX resistance gene, provide good geneticmarkers for herbicide resistance breeding. Significant correlations betweenherbicide and photosynthetic characters suggest that the evolution ofherbicide resistance polymorphisms may be related to the process ofphotosynthesis in nature and predated domestication of cultivated wheat.
156                                              NAL Call. No.: S494.5.B563N33Herbicide tolerance in crops. 1.Fehr, W.R.Ithaca, N.Y. : National Agricultural Biotechnology Council; 1991.NABC report / (3): p. 179-198; 1991.  In the series analytic: Agriculturalbiotechnology at the crossroads: biological, social and institutionalconcerns.  Proceedings of the National Agricultural Biotechnology Council'sthird annual meeting, May 1991.  Includes references.
Language:  English
Descriptors: Herbicides; Tolerance; Biotechnology
157                                              NAL Call. No.: QK658.A54 1992Herbicide tolerance in maize--genetics and pollen selection.Gorla, M.S.; Ferrario, S.; Gianfranceschi, L.; Villa, M.New York : Springer-Verlag; 1992.Angiosperm pollen and ovules / E. Ottaviano ... [et al., editors]. p. 364-369;1992.  Includes references.
Language:  English
Descriptors: Maize; Plant breeding; Selective breeding; Genetic resistance;Herbicides
158                                                 NAL Call. No.: SB610.2.B74Herbicide tolerance in winter oilseed rape.Lutman, P.J.W.; Dixon, F.L.Surrey : BCPC Registered Office; 1991.Brighton Crop Protection Conference-Weeds v. 1: p. 195-202; 1991.  Includesreferences.
Language:  English
Descriptors: Brassica napus; Weed control; Metazachlor; Tolerance; Pyridate;Fluroxypyr
159                                                   NAL Call. No.: 79.9 W52RHerbicide tolerance of seedling grasses for erosion control in a spottedknapweed infested parkland.Lass, L.W.; Callihan, R.H.S.l. : The Society; 1991.Research progress report - Western Society of Weed Science. p. 24-26; 1991.Meeting held March 12-14, 1991, Seattle, Washington.
Language:  English
Descriptors: Centaurea repens; Gramineae; Stand establishment; Weed control;Herbicides
160                                                     NAL Call. No.: SB1.J66Herbicide tolerance of selected ericaceous species.Skroch, W.A.; Warren, S.L.; Gallitano, L.B.Washington, D.C. : Horticultural Research Institute; 1991 Dec.Journal of environmental horticulture v. 9 (4): p. 196-198; 1991 Dec.Includes references.
Language:  English
Descriptors: Ornamental woody plants; Kalmia latifolia; Leucothoe walteri;Oxydendrum arboreum; Rhododendron; Rhododendron catawbiense; Rhododendronobtusum; Herbicide resistance; Herbicide mixtures; Phytotoxicity
161                                                NAL Call. No.: SB950.2.I3I4Herbicide tolerant crops.Graham, J.Urbana, Ill. : Cooperative Extension Service, Univ of Illinois atUrbana-Champaign; 1991.Illinois Agricultural Pesticides Conference summaries of presentations January8, 9, 10, 1991, Urbana, Illinois / Univ of Illinois at Urbana-Champaign, CoopExt Serv, in coop with the Illinois Natural History Survey. p. 167-169; 1991."Proceedings of the 1991 Illinois Agricultural Pesticides Conference," January8-10, 1991, Urbana, Illinois.
Language:  English
Descriptors: Crops; Herbicide resistance; Genetic engineering
162                                                   NAL Call. No.: SB951.P49Herbicide-insecticide interaction in maize: malathion inhibits cytochromeP450-dependent primisulfuron metabolism.Kreuz, K.; Fonne-Pfister, R.Orlando, Fla. : Academic Press; 1992 Jul.Pesticide biochemistry and physiology v. 43 (3): p. 232-240; 1992 Jul.Includes references.
Language:  English
Descriptors: Zea mays; Herbicide resistance; Sulfonylurea herbicides;Interactions; Organophosphorus insecticides; Phytotoxicity; Antagonism;Malathion; Metabolism; Metabolic detoxification; Cytochrome p-450; Enzymeactivity; Microsomes; Herbicide mixtures; Pharmacokinetics
Abstract:  Tolerance of maize to sulfonylurea herbicides such as primisulfuronhas recently been reported to be impaired by the use of some organophosphorusinsecticides. In an effort to elucidate the mechanism of this interaction, theeffect of the insecticide, malathion, on the metabolism of primisulfuron wasstudied in whole plants, in excised leaves, and in a microsomal in vitrosystem from maize. Foliar application of malathion to 7-day-old plants had noinfluence on leaf uptake and translocation of primisulfuron, but caused adecrease in the rate of herbicide metabolism. In excised leaves, malathionincreased the metabolic half-life of primisulfuron. In microsomalpreparations, malathion inhibited cytochrome P450-dependent primisulfuronphenyl- and pyrimidinering hydroxylation. Loss of primisulfuron phenyl-ringhydroxylase activity was time-dependent, saturable with respect to malathionconcentration, and attenuated in the absence of NADPH. The kinetic datasuggest a mechanism-based cytochrome P450 inactivation by malathion. Theoxoanalogue of malathion, malaoxon, did not influence the metabolic half-lifeof primisulfuron in excised leaves and was a poor inhibitor of microsomalprimisulfuron hydroxylation. Neither insecticide had any effect in vitro ontotal microsomal cytochrome P450 content. From the present results it may beconcluded that malathion affects primisulfuron tolerance of maize due to theinhibition of cytochrome P450 monooxygenases involved in herbicide metabolism.
163                                                   NAL Call. No.: 381 J825NHerbicide-resistant crops focus of biotechnology debate.Baum, R.M.Washington, D.C. : American Chemical Society; 1993 Mar08.Chemical and engineering news v. 71 (10): p. 38-41; 1993 Mar08.
Language:  English
Descriptors: U.S.A.; Herbicide resistance; Crops; Genetic engineering; Usda;Public opinion
164                                                   NAL Call. No.: QK710.P62Herbicide-resistant Indica rice plants from IRRI breeding line IR72 afterPEG-mediated transformation of protoplasts.Datta, S.K.; Datta, K.; Soltanifar, N.; Donn, G.; Potrykus, I.Dordrecht : Kluwer Academic Publishers; 1992 Nov.Plant molecular biology : an international journal on molecular biology,biochemistry and genetic engineering v. 20 (4): p. 619-629; 1992 Nov.Includes references.
Language:  English
Descriptors: Oryza sativa; Genetic transformation; Protoplasts; DirectDNAuptake; Polyethylene glycol; Gene transfer; Transgenics;Phosphotransferases; Drug resistance; Hygromycin b; Acyltransferases;Herbicide resistance; Glufosinate; Regenerative ability; Enzyme activity
Abstract:  The commercially important Indica rice cultivar Oryza sativa cv.IR72 has been transformed using direct gene transfer to protoplasts.PEG-mediated transformation was done with two plasmid constructs containingeither a CaMV 35S promoter/HPH chimaeric gene conferring resistance tohygromycin (Hg) or a CaMV 35S promoter/BAR chimaeric gene conferringresistance to a commercial herbicide (Basta) containing phosphinothricin(PPT). We have obtained so far 92 Hg(r) and 170 PPT(r) IR72 plants fromprotoplasts through selection. 31 Hg(r) and 70 PPT(r) plants are being grownin the greenhouse to maturity. Data from Southern analysis and enzyme assaysproved that the transgene was stably integrated into the host genome andexpressed. Transgenic plants showed complete resistance to high doses of thecommercial formulations of PPT.
165                                                   NAL Call. No.: 450 P5622Herbicide-resistant lines of microalgae: growth and fatty acid composition.Cohen, Z.; Reungjitchachawali, M.; Siangdung, W.; Tanticharoen, M.; Heimer,Y.M.Oxford ; New York : Pergamon Press, 1961-; 1993 Nov.Phytochemistry v. 34 (4): p. 973-978; 1993 Nov.  Includes references.
Language:  English
Descriptors: Rhodophyta; Spirulina; Algae; Eicosapentaenoic acid; Fatty acids;Growth; Herbicide resistance; Lines; Linolenic acid
Abstract:  Cell lines of Spirulina platensis and Porphyridium cruentumresistant to growth inhibition by the herbicide SAN 9785 had a significantlyhigher growth rate than their respective wild-type strains. These lines werealso shown to overproduce gamma-linolenic acid (GLA) and eicosapentaenoic acid(EPA), respectively, in the presence and absence of the inhibitor, as comparedwith wild-type cultures under similar conditions. The effect was mostconspicuous in polar lipids. Thus, the proportion of GLA in the galactolipid(GL) fraction of the SAN 9785-resistant strain of S. platensis, SRS-1,increased in the absence of the inhibitor from 33.3% in the wild-type to39.0%. Similarly, the proportion of EPA in the GL fraction of the resistantstrain of P. cruentum, SRP, increased in the presence of the inhibitor from29.1 to 45.4%.
166                                                     NAL Call. No.: 10 J822Herbicide-resistant weeds: a worldwide perspective.Moss, S.R.; Rubin, B.Cambridge : Cambridge University Press; 1993 Apr.The Journal of agricultural science v. 120 (pt.2): p. 141-148; 1993 Apr.Literature review.  Includes references.
Language:  English
Descriptors: Herbicide resistant weeds; Incidence; Literature reviews; Models;Resistance mechanisms; Herbicides
167                                                NAL Call. No.: 275.29 W27PnHerbicide-resistant weeds and their management.Mallory-Smith, C.; Thill, D.; Morishita, D.Corvallis, Or. : Washington, Oregon, and Idaho State Universities, CooperativeExtension Service; 1993.PNW [1993?] (437): 4 p.; 1993.
Language:  English
Descriptors: Herbicide resistant weeds; Biotypes; Weed control; Herbicides
168                                                    NAL Call. No.: 79.8 W41Herbicides that inhibit acetohydroxyacid synthase.Stidham, M.A.Champaign, Ill. : Weed Science Society of America; 1991 Jul.Weed science v. 39 (3): p. 428-434; 1991 Jul.  Paper presented at the"Symposium on Herbicide Mechanism of Action," February 7, 1990, Montreal,Canada.  Includes references.
Language:  English
Descriptors: Sulfonylurea herbicides; Imidazolinone herbicides; Mode ofaction; Enzyme inhibitors; Ligases; Herbicidal properties; Protein synthesisinhibitors; Structure activity relationships; Herbicide resistance; Zea mays;Resistance mechanisms
Abstract:  Acetohydroxyacid synthase was discovered as the site of action ofimidazolinone and sulfonylurea herbicides over 6 yr ago. In recent years,advances have been made in the understanding of this enzyme as a herbicidetarget site. Derivatives of both imidazolinones and sulfonylureas have yieldednew herbicide chemistry. All of the herbicides display unusual "slow-binding"behavior with the enzyme, and this behavior may help explain efficacy of theherbicides. Resistance to these herbicides has been developed through a numberof different procedures, and the mechanism of resistance is through changes insensitivity of the enzyme to the herbicides. The changes are either selectiveto only one class of chemistry, or broad to a number of classes of chemistry.These data support the idea that binding sites for the herbicides on theenzyme are only partially overlapping. Progress in purification of AHAS fromcorn includes discovery of the existence of the enzyme in monomer and oligomeraggregation states. The interaction of the enzyme with the herbicides isaffected by enzyme aggregation state.
169                                                      NAL Call. No.: A00109Herbicide-tolerant crops dominate testing in the industrialized world.Washington, DC : National Biotechnology Policy Center of the National WildlifeFederation; 1993 May.The gene exchange v. 4 (1): p. 3; 1993 May.
Language:  English
Descriptors: Herbicide resistance; Field tests
170                                                   NAL Call. No.: 442.8 Z34High frequency, heat treatment-induced inactivation of the phosphinothricinresistance gene in transgenic single cell suspension cultures of Medicagosativa.Walter, C.; Broer, I.; Hillemann, D.; Puhler, A.Berlin, W. Ger. : Springer International; 1992 Nov.M G G : Molecular and general genetics v. 235 (2/3): p. 189-196; 1992 Nov.Includes references.
Language:  English
Descriptors: Medicago sativa; Genetic transformation; Transgenics; Structuralgenes; Acyltransferases; Glufosinate; Herbicide resistance; Gene expression;Cell suspensions; Genetic regulation; Heat; Callus; Regenerative ability;Enzyme activity
Abstract:  One descendant of the Medicago sativa Ra-3 transformant T304 wasanalysed with respect to the somatic stability of the syntheticphosphinothricin-N-acetyltransferase (pat) gene which was used as a selectivemarker and was under the control of the 5'/3' expression signals of thecauliflower mosaic virus (CaMV) gene VI. In order to quantify geneinstability, we developed a system for culturing and regenerating individualcells. Single cell suspension cultures derived from T304 and the ancestralnon-transgenic M. sativa cultivar Ra-3, were established. The cells wereregenerated into monoclonal calli. In transgenic calli, the phosphinothricin(Pt)-resistance phenotype was retained after more than 2 months ofnon-selective growth. In contrast, up to 12% of the suspension culture cellsgrown under non-selective conditions and at constant temperature (25 degreesC) lost the herbicide-resistance phenotype within 150 days. Surprisingly, aheat treatment (37 degrees C), lasting for 10 days, during the culture periodresulted in an almost complete (95%) loss of the Pt resistance of thesuspension culture cells. However, the frequency of cell division wasidentical in cultures grown under normal and heat treatment conditions. Abiochemical test revealed that no phosphinothricin-N-acetyltransferaseactivity was present in heat treated, Pt-sensitive cells. The resistance levelof the Pt-sensitive transgenic cells was equivalent to that of the wild-typecells. A PCR analysis confirmed the presence of the pat gene in heat treated,Pt-sensitive cells. From these results it is concluded that the Pt resistancegene was heat-inactivated at a high frequency in the M. sativa suspensioncultures.
171                                                   NAL Call. No.: SB610.W39History of herbicide--tolerant crops, methods of development and current stateof the art--emphasis on glyphosate tolerance.Kishore, G.M.; Padgette, S.R.; Fraley, R.T.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 626-634; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Literature review.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Herbicide resistance; Glyphosate; Weedcontrol; Chemical control; Gene transfer; Biotechnology; Research; Literaturereviews
172                                                   NAL Call. No.: SB610.W39History of identification of herbicide-resistant weeds.Holt, J.S.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America. p.615-620; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Herbicide resistant weeds; Herbicide resistance; Detection;Biotypes; Cross resistance; Resistance mechanisms; Weed control; Chemicalcontrol; History
173                                                      NAL Call. No.: SB1.H6ID-BR1: sulfonylurea herbicide-resistant lettuce germplasm.Mallory-Smith, C.; Thill, D.C.; Dial, M.J.Alexandria, Va. : American Society for Horticultural Science; 1993 Jan.HortScience v. 28 (1): p. 63-64; 1993 Jan.  Includes references.
Language:  English
Descriptors: Lactuca sativa; Lactuca serriola; Germplasm; Herbicideresistance; Sulfonylurea herbicides; Plant breeding
174                                                   NAL Call. No.: 64.8 C883Identification and inheritance of metribuzin tolerance in wild soybean.Kilen, T.C.; He, G.Madison, Wis. : Crop Science Society of America; 1992 May.Crop science v. 32 (3): p. 684-685; 1992 May.  Includes references.
Language:  English
Descriptors: Glycine max; Wild plants; Metribuzin; Herbicide resistance;Germplasm; Diversity; Genetic regulation; Alleles; Loci; Gene location;Inheritance; Plant breeding
Abstract:  An economically important agronomic trait that has not beenevaluated extensively in the wild soy (Glycine soja Sieb. & Zucc.) istolerance to herbicides. Identification and genetic characterization oftolerance to a widely used herbicide, metribuzin[4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4.triazin-5(4H)-one], in G.soja may help provide greater diversity in the gene pool for this trait. Thisstudy was conducted to identify tolerance to metribuzin in the wild soybeanand to determine the genetic control of the trait. Crosses were made frommetribuzin-tolerant G. soja selections and metribuzin-sensitive selections ofG. max (L.) Merr. The F1, F2, and F3 populations from these crosses were grownhydroponically, and evaluated for reaction to a concentration of 125 microgramL-1 metribuzin. The F1 plants were tolerant, the F2 population segregated in a3 tolerant: 1 sensitive ratio, and the F2 population segregated in 1 tolerant:2 segregating: 1 sensitive ratio, suggesting a single dominant genecontrolling tolerance. The F2 populations from crosses betweenmetribuzin-tolerant G. soja accessions and the metribuzin-tolerant cultivarTracy-M were all tolerant. This indicates that tolerance to metribuzin inthese two wild soybean accessions is controlled by alleles at the same locusas the Hm gene in Tracy-M. Therefore, the metribuzin tolerance in the wildsoybean is probably the same as that found in most of the cultivated soybeanaccessions and in most commercial cultivars. The significance of identifyingtolerance to a currently used herbicide in the wild soybean is the suggestionthat other useful traits needed in modern agriculture may be found in thisprimitive gene pool.
175                                                   NAL Call. No.: SB610.W39Imazaquin absorption, translocation, and metabolism in flue-cured tobacco.Walls, F.R. Jr; Corbin, F.T.; Collins, W.K.; Worsham, A.D.; Bradley, J.R. JrChampaign, Ill. : The Weed Science Society of America; 1993 Apr.Weed technology : a journal of the Weed Science Society of America v. 7 (2):p. 370-375; 1993 Apr.  Includes references.
Language:  English
Descriptors: North Carolina; Cabt; Nicotiana tabacum; Herbicide resistance;Imazaquin; Leaves; Absorption; Translocation; Metabolism; Seedling stage;Source sink relations; Roots; Shoots; Foliar application; Soil treatment; Weedcontrol; Chemical control; Phytotoxicity
176                                                   NAL Call. No.: SB951.P49Increased detoxification is a mechanism of simazine resistance in Loliumrigidum.Burnet, M.W.M.; Loveys, B.R.; Holtum, J.A.M.; Powles, S.B.Orlando, Fla. : Academic Press; 1993 Jul.Pesticide biochemistry and physiology v. 46 (3): p. 207-218; 1993 Jul.Includes references.
Language:  English
Descriptors: Lolium rigidum; Biotypes; Weeds; Herbicide resistance;Susceptibility; Simazine; Resistance mechanisms; Metabolic detoxification;Metabolism; Metabolites; Metabolic inhibitors; Thylakoids; Oxygen; Uptake;Translocation; Heritability
Abstract:  Biotypes of Lolium rigidum Gaud. (annual ryegrass) resistant to thetriazine herbicides were studied to determine the mechanism of resistance. Theresistant biotypes have different histories of exposure to the herbicideatrazine but both exhibit greater resistance to the structurally similartriazine herbicide simazine. Simazine resistance is not due to a change at thetarget site, as a similar concentration of simazine is required for a 50%reduction in electron transport by thylakoids isolated from resistant andsusceptible biotypes. Uptake of simazine from nutrient solution anddistribution of simazine between the roots and the shoots are similar inresistant and susceptible biotypes. Following application to the roots, morethan 95% of the absorbed simazine was translocated to the shoots in bothresistant and susceptible biotypes. Resistant biotypes metabolized[14C)simazine at a greater rate than susceptible plants when simazine wassupplied as either a 12-hr pulse or continuously over 7 days. Over a 7-dayexposure to simazine (3 micromolar), susceptible plants accumulated simazinein their shoot tissues, whereas resistant plants maintained a low and stableamount of simazine by metabolizing simazine at a greater rate than thesusceptible plants. The primary products of simazine metabolism weretentatively identified as N-de-ethyl derivatives. Up to eight other minormetabolites were also observed. The cytochrome P450 inhibitor1-aminobenzotriazole (ABT) (70 micromolar) in combination with simazine (3micromolar) for 7 days caused a greater reduction in dry weight of resistantplants than simazine applied alone. ABT inhibited the metabolism of simazineby all biotypes whether applied as a 12-hr pulse or over a 7-day period. Inthe presence of ABT the amount of simazine in the resistant shoot tissue wassimilar to that in susceptible plants treated with simazine alone. The natureof the metabolites and the inhibition of metabolism by ABT suggest theinvolvement of oxidative enzymes in the mechanism of resistance to simazine.
177                                                    NAL Call. No.: 500 N21PIncreased resistance to oxidation stress in transgenic plants that overexpresschloroplastic Cu/Zn superoxide dismutase.Gupta, A.S.; Heinen, J.L.; Holaday, A.S.; Burke, J.J.; Allen, R.D.Washington, D.C. : The Academy; 1993 Feb15.Proceedings of the National Academy of Sciences of the United States ofAmerica v. 90 (4): p. 1629-1633; 1993 Feb15.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Transgenics; Chloroplasts; Gene expression;Genetic code; Oxidation; Photoinhibition; Stress; Superoxide dismutase;Herbicide resistance
Abstract:  Transgenic tobacco plants that express a chimeric gene that encodeschloroplast-localized Cu/Zn superoxide dismutase (SOD) from pea have beendeveloped. To investigate whether increased expression of chloroplast-targetedSOD could after the resistance of photosynthesis to environmental stress,these plants were subjected to chilling temperatures and moderate (500micromole of quanta per m2 per s) or high (1500 micromole of quanta per m2 pers) light intensity. During exposure to moderate stress, transgenic SOD plantsretained rates of photosynthesis approximately 20% higher than untransformedtobacco plants, implicating active oxygen species in the reduction ofphotosynthesis during chilling. Unlike untransformed plants, transgenic SODplants were capable of maintaining nearly 90% of their photosynthetic capacity(determined by their photosynthetic rates at 25 degrees C) following exposureto chilling at high light intensity for 4 hr. These plants also showed reducedlevels of light-mediated cellular damage from the superoxide-generatingherbicide methyl viologen. These results demonstrate that SOD is a criticalcomponent of the active-oxygen-scavenging system of plant chloroplasts andindicate that modification of SOD expression in transgenic plants can improveplant stress tolerance.
178                                                    NAL Call. No.: 450 P693Increased sterol biosynthesis in tobacco calli resistant to a triazoleherbicide which inhibits demethylation of 14alpha-methyl sterols.Schaller, H.; Maillot-Vernier, P.; Belliard, G.; Benveniste, P.Berlin : Springer-Verlag; 1992.Planta v. 187 (3): p. 315-321; 1992.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Callus; Sterols; Biosynthesis; Triazoleherbicides; Herbicide resistance; Biochemical pathways; Methylation
Abstract:  The gamma-keto triazole derivative4,4-dimethyl-1-(2-methoxyphenyl)-1-(1,2,4-triazol-1-yl)-1-penten-3-one istoxic to Nicotiana tabacum L. cv. Xanthi plants or cell cultures. Analysis ofthe sterol composition of treated wild-type plant material demonstrates thatthis herbicide is an inhibitor of the C-14 alpha-methyl demethylation processin sterol biosynthesis. Selection experiments, consisting of screening largepopulations of microcalli derived from UV-mutagenized tobacco protoplasts forresistance to a lethal dose (1 mg.l-1) of the gamma-keto triazole, haveresulted in the recovery of two groups of resistant calli. In the first group,selected calli show a sterol composition in the absence or presence of theinhibitor very similar to that of wild-type sensitive calli, whereas in thesecond group the main feature of the selected calli is a new sterol profile.These calli present an overproduction of sterols with a concomitantesterification of overproduced metabolites, just as it was demonstrated forcalli previously selected in our laboratory for resistance to LAB 170250F, atriazole fungicide (Maillot-Vernier et al., 1991, Mol. Gen. Genet. 231,33-40).
179                                                   NAL Call. No.: TA166.T72Indiscriminate use of selectable markers--sowing wild oats?.Gressel, J.New York, N.Y. : Elsevier Science Publishing Co; 1992 Nov.Trends in biotechnology v. 10 (11): p. 382; 1992 Nov.  Includes references.
Language:  English
Descriptors: Avena fatua; Genetic markers; Marker genes; Herbicide resistance;Glufosinate; Gene transfer; Avena sativa; Transgenics; Biotechnology
180                                                   NAL Call. No.: SB951.P49Induced microsomal oxidation of diclofop, triasulfuron, chlorsulfuron, andlinuron in wheat.Frear, D.S.; Swanson, H.R.; Thalacker, F.W.Orlando, Fla. : Academic Press; 1991 Nov.Pesticide biochemistry and physiology v. 41 (3): p. 274-287; 1991 Nov.Includes references.
Language:  English
Descriptors: Triticum aestivum; Seedlings; Shoots; Metabolic detoxification;Diclofop; Chlorsulfuron; Triasulfuron; Linuron; Herbicide resistance;Phytotoxicity; Selectivity; Oxidation; Microsomes; Enzyme activity; Monophenolmonooxygenase; Nadh dehydrogenase; Cytochrome p-450; Oxygenases;Characterization; Pharmacokinetics
Abstract:  Microsomal fractions from shoot tissues of etiolated wheatseedlings catalyzed the oxidation of diclofop, chlorsulfuron, triasulfuron,chlortoluron, and linuron. Microsomal oxidation products of chlorsulfuron,triasulfuron, and linuron were isolated and identified by mass spectrometryand cochromatography with reference standards. Oxidation was dependent onNADPH and molecular oxygen and was inhibited by CO in the presence of oxygen.Triasulfuron hydroxylation was inhibited to varying degrees by other knowninhibitors of cytochrome P-450 enzymes and by several different postemergenceherbicides. Enzyme activity was increased 2- to 3-fold by the removal ofendogenous inhibitors and stimulated an additional 5- to 20-fold by thetreatment of germinating seedlings with naphthalic anhydride, ethanol, orphenobarbital. In contrast to marked increases in monooxygenase activitiesfollowing induction, microsomal cytochrome P-450 levels and NADPH cytochrome creductase activities were not increased to a significant extent. Ethanol andphenobarbital were more effective than naphthalic anhydride as inducers ofmicrosomal hydroxylase activity. The combined effect of naphthalic anhydrideand ethanol as inducers of diclofop and triasulfuron hydroxylases wasadditive. Apparent Km values for triasulfuron, chlorsulfuron, and diclofopwith constitutive and induced microsomal hydroxylases were compared.Differences in the response of herbicide monooxygenases to selectedinhibitors, inducers, and substrates support the hypothesis that wheatmicrosomes contain a number of distinct cytochrome P-450-dependentmonooxygenases with different substrate specificities and kinetic properties.These enzymes serve as important factors in the tolerance and selectivity of abroad spectrum of herbicides used in wheat production systems.
181                                              NAL Call. No.: SB349.D44 1992Induced plant cell modifications analysis of herbicide-resistant tomato cellspossessing altered cell wall composition..  Induces plant cell wallmodificationsDelmer, Deborah P.; Lamport, D. T. A.United States-Israel Binational Agricultural Research and Development FundBet Dagan, Israel : BARD,; 1992.1 v. (various pagings) : ill. ; 29 cm.  Cover title: Induces plant cell wallmodifications.  Final report.  Project no. IS-1386-87.  Includesbibliographical references.
Language:  English
Descriptors: Tomatoes; Plant cell walls
182                        NAL Call. No.: MdULD3231.M70d Bandaranayake, H.A.D.Induction, transformation and characterization of herbicide resistance inNicotiana.Bandaranayake, Hema Anura DivaleUniversity of Maryland at College Park, Dept. of Botany1992; 1992.vii, 84 leaves : ill. ; 29 cm.  Thesis research directed by Dept. of Botany.Includes bibliographical references (leaves 70-84).
Language:  English
Descriptors: Tobacco; Plants, Effect of herbicides on
183                                                   NAL Call. No.: SB610.W39An industry perspective on herbicide-tolerant crops.Giaquinta, R.T.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 653-656; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Herbicide resistance; Biotechnology;Industry; Weed control
184                                                   NAL Call. No.: 79.8 W412Influence of light intensity on growth of triazine-resistant rapeseed(Brassica napus).Hart, J.J.; Radosevich, S.R.; Stemler, A.Oxford : Blackwell Scientific Publications; 1992 Oct.Weed research v. 32 (5): p. 349-356; 1992 Oct.  Includes references.
Language:  English
Descriptors: Brassica napus; Lines; Selection criteria; Herbicide resistance;Triazines; Crossing; Light intensity; Growth; Dry matter accumulation;Responses; Greenhouse culture; Growth chambers; Photosynthesis; Performance
185                                                    NAL Call. No.: 23 AU783Influence of rainfall and temperature on sensitivity of barley (Hordeumvulgare) to Chlorsulfuron.Lemerle, D.Melbourne : Commonwealth Scientific and Industrial Research Organization;1993.Australian journal of agricultural research v. 44 (1): p. 23-32; 1993.Includes references.
Language:  English
Descriptors: New South Wales; Hordeum vulgare; Cultivars; Crop damage;Herbicide resistance; Phytotoxicity; Chlorsulfuron; Rain; Temperature
186                                                    NAL Call. No.: 442.8 Z8Inheritance of bipyridyl herbicide resistance in Arctotheca calendula andHordeum leporinum.Purba, E.; Preston, C.; Powles, S.B.Berlin, W. Ger. : Springer International; 1993 Dec.Theoretical and applied genetics v. 87 (5): p. 598-602; 1993 Dec.  Includesreferences.
Language:  English
Descriptors: Arctotheca calendula; Hordeum murinum subsp. leporinum;Inheritance; Herbicide resistance; Paraquat; Diquat; Segregation; Biotypes;Genes; Dominance; Herbicide resistant weeds
Abstract:  The mode of inheritance of resistance to bipyridyl herbicides inbipyridyl-resistant biotypes of Arctotheca calendula and of Hordeum leporinumwas investigated. F1 plants from reciprocal crosses between diquat-resistantand -susceptible plants of A. calendula showed an intermediate response todiquat application that was nuclearly inherited. Treatment of F2 plants with100 g ai ha-1 of diquat or 800 g ai ha-1 of paraquat killed allhomozygous-susceptible plants, caused severe injury to heterozygous plants butonly slight or no injury to homozygous-resistant plants. Back crosses of F1 tosusceptible plants exhibited intermediate and susceptible phenotypes. Theobserved segregation ratios in F2 and test-cross populations fitted predictedsegregation ratios, 1:2:1 (R:I:S) and 1:1 (I:S) respectively, showing thatbipyridyl resistance is conferred by a single incompletely-dominant gene.Biotypes of paraquat-resistant and -susceptible H. leporinum were crossedreciprocally. F1 plants from reciprocal crosses showed an intermediateresponse to paraquat application. The F2 progeny showed segregation ratiosthat fitted the predicted segregation ratio of 1:2:1 (R:I:S) for inheritanceof resistance being governed by a single partially-dominant gene.
187                                                    NAL Call. No.: 470 C16CInheritance of two mutations conferring glyphosate tolerance in the fernCeratopteris richardii.Chun, P.T.; Hickok, L.G.Ottawa, Ont. : National Research Council of Canada; 1992 May.Canadian journal of botany; Journal canadien de botanique v. 70 (5): p.1097-1099; 1992 May.  Includes references.
Language:  English
Descriptors: Ceratopteris; Genotypes; Herbicide resistance; Inheritance;Mutations; Glyphosate
188                                                   NAL Call. No.: SB951.P47Inhibition of acetolactate synthase in susceptible and resistant biotypes ofStellaria media.Devine, M.D.; Marles, M.A.S.; Hall, L.M.Essex : Elsevier Applied Science Publishers; 1991.Pesticide science v. 31 (3): p. 273-280; 1991.  Includes references.
Language:  English
Descriptors: Alberta; Stellaria media; Lyases; Biotypes; Cross resistance;Enzyme inhibitors; Herbicide resistance; Susceptibility; Chlorsulfuron;Sulfonylurea herbicides; Weed control
Abstract:  Acetolactate synthase (ALS) from one susceptible and twochlorsulfuron-resistant biotypes of Stellaria media (L.) Vill. was assayed inthe presence of eight known ALS inhibitors. As expected, ALS from thechlorsulfuron-resistant biotypes (R1 and R2) showed reduced sensitivity tochlorsulfuron and other sulfonylurea herbicides. The patterns ofcross-resistance varied, however, indicating that the alteration in ALS thatconfers chlorsulfuron resistance does not confer the same level of resistanceto other sulfonylurea herbicides. The resistant biotypes were highlycross-resistant to sulfometuron-methyl and DPX-A7881, but less cross-resistantto triasulfuron. Both R1 and R2 were highly cross-resistant to DTPS(N-[2,6-dichlorophenyl]-5,7-dimethyl-1,2,4-triazolo[1,5a]pyrimidine-2-sulfonamide), but only slightly cross-resistant to imazamethabenz, animidazolinone herbicide. The differences in the patterns of cross-resistanceobserved presumably reflect differences in the binding affinity of theherbicides for the altered ALS. The data presented suggest, but do notconfirm, that R1 and R2 contain the same ALS mutation.
189                                           NAL Call. No.: SB123.57.I55 1992Instability of herbicide resistance in transgenic suspension cultures andplants.Broer, I.; Droge, W.; Hillemann, D.; Neumann, K.; Walter, C.; Puhler, A.Braunschweig, Germany : Biologische Bundesanstalt fur Land- undForstwirtschaft; 1992.Proceedings of the 2nd International Symposium on the Biosafety Results ofField Tests of Genetically Modified Plants and Microorganisms : May 11-14,1992, Goslar, Germany : edited by R. Casper and J. Landsmann. p. 230-238;1992.  Includes references.
Language:  English
Descriptors: Plants; Transgenics; Genetic engineering; Herbicide resistance
190                                                   NAL Call. No.: SB610.W39International organization for resistant pest management (IOPRM)-- a steptoward rational resistance management recommendations.Lebaron, H.M.; Gressel, J.; Smale, B.C.; Horne, D.M.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 765-770; 1992 Jul.  Includes references.
Language:  English
Descriptors: International organizations; Herbicide resistant weeds; Weedcontrol; Pest management; Pest resistance
191                                                  NAL Call. No.: QH431.G452Interspecific hybrids between a transgenic rapeseed (Brassica napus) andrelated species: cytogenetical characterization and detection of thetransgene.Kerlan, M.C.; Chevre, A.M.; Eber, F.Ottawa, Ontario, Canada : National Research Council Canada; 1993 Dec.Genome / v. 36 (6): p. 1099-1106; 1993 Dec.  Includes references.
Language:  English
Descriptors: Brassica napus; Brassica oleracea; Brassica oleracea var.capitata; Brassica; Brassica nigra; Sinapis arvensis; Raphanus raphanistrum;Interspecific hybridization; Hybrids; Transgenic plants; Introgression;Reporter genes; Acyltransferases; Cytogenetics; Chromosome pairing; Meiosis;Glufosinate; Herbicide resistance
Abstract:  In interspecific hybrids produced between a transgenic rapeseed, anallotetraploid species, resistant to herbicide, phosphinotricin, and fivediploid related species. the risk for gene introgression in weed genomes wasexplored through cytogenetic and bar gene characterizations. Among the 75hybrids studied, most had the expected triploid structure, with the exceptionof B. napus--B. oleracea amphidiploid plants and one B. napus--S. arvensisamphidiploid plant. In triploid hybrid plants, the reciprocal hybrids did notexhibit any difference in their meiotic behavior. The comparison of thepercentage of chromosome pairing in the hybrids with that of haploid rapeseedpermit to conclude that allosyndesis between AC genomes and related speciesgenomes took place. This possibility of recombination was confirmed by thepresence of multivalent associations in all the interspecific hybrids.Nevertheless, in B. napus--B. adpressa hybrids a control of chromosome pairingseemed to exist. The possibility of amphidiploid plant production directlyobtained in the F1 generation increased the risk of gene dispersal. The B.napus--B. oleracea amphidiploid plant presented a meiotic behavior moreregular than that of the B. napus--S. arvensis amphidiploid plant. Concerningthe herbicide bar gene characterization, the presence of the gene detected byDNA amplification was correlated with herbicide resistance, except for twoplants. Different hypotheses were proposed to explain these results. Aclassification of the diploid species was established regarding their genedispersal risk based on the rate of allosyndesis between chromosomes of ACgenomes of rapeseed and the genomes of the related species.
192                                       NAL Call. No.: Videocassette no.1003Introduction to genetics and biotechnology DNA technology by Paul J. Bottino ;directed/recorded by Ron Young..  NAL genetics lecture DNA technologyBottino, P. J.National Agricultural Library (U.S.)Beltsville, Md.? : National Agricultural Library,; 1991.2 videocassettes (190 min.) : sd., col. ; 1/2 in. (NAL lecture series ; seriesno. 1).  VHS.  June 17, 1991.  Title on cassette label: NAL genetics lecture.Susan McCarthy, Coordinator, Plant Genome Data and Information Center.
Language:  English
Descriptors: Genetics; Restriction enzymes, DNA; Plant genetic engineering
Abstract:  Discusses restriction enzymes and how they are used to cut DNA,restriction sites, enzyme recognition, bacterial plasmids, use ofcomplementary base pairing, enzymology, and gel electrophoresis. Alsodiscusses how DNA technology is use for plant disease, virus and herbicideresistance and for gene therapy.
193                                                   NAL Call. No.: SB951.P49Investigation of the mechanism of diclofop resistance in two biotypes of Avenafatua.Devine, M.D.; MacIsaac, S.A.; Romano, M.L.; Hall, J.C.Orlando, Fla. : Academic Press; 1992 Jan.Pesticide biochemistry and physiology v. 42 (1): p. 88-96; 1992 Jan.  Includesreferences.
Language:  English
Descriptors: Avena fatua; Biotypes; Physiological races; Herbicide resistance;Diclofop; Absorption; Translocation; Metabolism; Metabolic detoxification;Pharmacokinetics; Metabolites; Phytotoxicity; Enzyme activity; Acetyl-coacarboxylase
Abstract:  The mechanism of diclofop resistance was investigated in twobiotypes of wild oat (Avena fatua L.) that show approximately 12-foldresistance to diclofop compared to a typical susceptible biotype. Absorptionand translocation of 14C following application of [14C]diclofop-methyl did notdiffer among the three biotypes; approximately 95% of the applieddiclofop-methyl was absorbed into the foliage 48 hr after application, andmost of this (> 80%) was retained in the treated area in all biotypes.Metabolism of diclofop-methyl, examined by TLC and HPLC, did not differ amongthe three biotypes. Although results of the TLC and HPLC analyses differedslightly, the amount of free diclofop (acid) was generally consistent amongthe three biotypes. There were no apparent differences in the nature of thepolar metabolites formed in the susceptible and tolerant biotypes. Wheat,which is tolerant of diclofop-methyl, metabolized the herbicide considerablyfaster than the three wild oat biotypes. Acetyl-coenzyme A carboxylaseextracted from the resistance and susceptible biotypes was equally sensitiveto diclofop in the range 10(-7) to 10(-4) M, indicating that diclofopresistance is not due to differences at the herbicide target site. Furtherresearch is required to explain diclofop resistance in these wild oatbiotypes.
194                                                     NAL Call. No.: S79 .E3Kenaf tolerance to various postemergence herbicides registered for other cropsgrown in the delta of Mississippi.Kurtz, M.E.; Weill, S.W.State College, Miss. : Mississippi State University, Agricultural and ForestryExperiment Station, 1970-; 1993 May.Bulletin (997): 7 p.; 1993 May.  Includes references.
Language:  English
Descriptors: Mississippi; Cabt; Hibiscus cannabinus; Herbicide resistance;Herbicides; Weed control; Phytotoxicity; Growth effects; Field tests
195                                                 NAL Call. No.: SB610.2.B74Kinetics of chlorophyll fluorescence decay in triazine-resistant and-susceptibile weeds.Benyamini, Y.; Schonfeld, M.; Rubin, B.Surrey : BCPC Registered Office; 1991.Brighton Crop Protection Conference-Weeds v. 3: p. 1103-1110; 1991.  Meetingheld November 18-21, 1991, Brighton, England.  Includes references.
Language:  English
Descriptors: Weeds; Chlorophyll; Fluorescence; Herbicide resistance;Susceptibility; Weed biology
196                                                    NAL Call. No.: 450 P692Lack of cross-resistance of imazaquin-resistant Xanthium strumariumacetolactate synthase to flumetsulam and chlorimuron.Schmitzer, P.R.; Eilers, R.J.; Cseke, C.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Sep.Plant physiology v. 103 (1): p. 281-283; 1993 Sep.  Includes references.
Language:  English
Descriptors: Xanthium strumarium; Cross resistance; Herbicide resistant weeds;Imazaquin; Lyases; Weed control; Chlorimuron; Herbicides
Abstract:  Acetolactate synthase (ALS) was isolated from a field population ofcocklebur (Xanthium strumarium) that developed resistance to the herbicideScepter following three consecutive years of application. The activeingredient of Scepter, imazaquin, gave an inhibitor concentration required toproduce 50% inhibition of the enzyme activity that was more than 300 timesgreater for the resistant enzyme than for the wild-type cocklebur ALS. Testswith flumetsulam and chlorimuron show that the resistant ALS was notcross-resistant to these two other classes of ALS inhibitors.
197                                                      NAL Call. No.: A00109The latest on transgenic herbicide-tolerant crops.Washington, DC : National Biotechnology Policy Center of the National WildlifeFederation; 1991 Jun.The gene exchange v. 2 (2): p. 10; 1991 Jun.
Language:  English
Descriptors: U.S.A.; Herbicide resistance; Transgenics; Crops; Usda; Fieldtests
198                                                     NAL Call. No.: 10 J822The location and effects of genes modifying the response of wheat to theherbicide difenzoquat.Leckie, D.; Snape, J.W.Cambridge : Cambridge University Press; 1992 Feb.The Journal of agricultural science v. 118 (pt.1): p. 9-15; 1992 Feb.Includes references.
Language:  English
Descriptors: Triticum; Polyploidy; Gene transfer; Genotypes; Herbicideresistance; Susceptibility; Difenzoquat
199                                                   NAL Call. No.: QK710.P55Magnesium deficiency enhances resistance to paraquat toxicity in bean leaves.Cakmak, I.; Marschner, H.Oxford : Blackwell Scientific Publications; 1992 Oct.Plant, cell and environment v. 15 (8): p. 955-960; 1992 Oct.  Includesreferences.
Language:  English
Descriptors: Phaseolus vulgaris; Paraquat; Phytotoxicity; Magnesium; Mineraldeficiencies; Herbicide resistance; Leaves; Light intensity; Oxygen; Freeradicals; Chlorophyll; Degradation
200                                                   NAL Call. No.: SB951.P49Mechanism of diclofop resistance in an Italian ryegrass (Lolium multiflorumLam.) biotype.Gronwald, J.W.; Eberlein, C.V.; Betts, K.J.; Baerg, R.J.; Ehlke, N.J.; Wyse,D.L.Orlando, Fla. : Academic Press; 1992 Oct.Pesticide biochemistry and physiology v. 44 (2): p. 126-139; 1992 Oct.Includes references.
Language:  English
Descriptors: Oregon; Lolium multiflorum; Biotypes; Herbicide resistance;Diclofop; Haloxyfop; Sethoxydim; Quizalofop; Cyclohexene oxime herbicides;Herbicide resistant weeds; Enzyme activity; Acetyl-coa carboxylase; Resistancemechanisms; Pharmacokinetics; Translocation; Metabolism
Abstract:  The biochemical basis for diclofop resistance in an Italianryegrass (Lolium multiflorum Lam.) biotype discovered in Oregon was examined.Herbicide rates that inhibited shoot growth by 50% (GR50 values) weredetermined for two aryloxyphenoxypropionic acid herbicides (diclofop,haloxyfop) and one cyclohexanedione herbicide (sethoxydim). As compared to awild type Italian ryegrass biotype, the GR50 values for diclofop, haloxyfop,and sethoxydim were approximately 130-, 22-, and 2-fold greater, respectively,for the resistant biotype. There were little or no differences in theretention, absorption, translocation, or metabolism of diclofop-methyl inresistant and susceptible biotypes. The susceptibility of acetyl-CoAcarboxylase (ACCase) to inhibition by selected graminicide herbicides wasevaluated in extracts from etiolated shoots of both resistant and susceptiblebiotypes. The herbicide concentrations that inhibited ACCase activity by 50%(I50 values) for diclofop, haloxyfop, and quizalofop were approximately 28-,9-, and 10-fold greater, respectively, for the enzyme from the resistantbiotype. For the cyclohexanedione herbicides, sethoxydim and clethodim, theI50 values for ACCase were similar for both biotypes. It is concluded thatresistance to diclofop and other aryloxyphenoxypropionic acid herbicides inthe Italian ryegrass biotype from Oregon is due to the presence of a tolerantform of ACCase. This modification confers tolerance to thearyloxyphenoxypropionic acids but little or no tolerance to thecyclohexanediones.
201                                                    NAL Call. No.: 79.8 W41Mechanism of inheritance of diclofop resistance in Italian ryegrass (Loliummultiflorum).Betts, K.J.; Ehlke, N.J.; Wyse, D.L.; Gronwald, J.W.; Somers, D.A.Champaign, Ill. : Weed Science Society of America; 1992 Apr.Weed science v. 40 (2): p. 184-189; 1992 Apr.  Includes references.
Language:  English
Descriptors: Oregon; Lolium multiflorum; Herbicide resistance; Herbicideresistant weeds; Diclofop; Biotypes; Inheritance; Maternal effects;Phenotypes; Susceptibility; Enzyme activity; Acetyl-coa carboxylase
Abstract:  A diclofop-methyl-resistant biotype of Italian ryegrass wascharacterized to determine the expression and inheritance of herbicideresistance and whether this trait was due to the presence of adiclofop-insensitive form of acetyl-coenzyme A carboxylase (ACCase). At thewhole plant level, the resistant biotype was > 93-fold more resistant todiclofop-methyl than the susceptible biotype. Crosses of diclofop-resistantand -susceptible plants were performed to produce F1 plants. No maternaleffects were evident in responses of reciprocal F1 plants to diclofop. GR50diclofop rates determined for resistant, F1, and susceptible plants were 15,6.3, and 0.16 kg ha-1, respectively. F2 populations treated with a 7.5 kg ha-1rate of diclofop exhibited three injury response phenotypes 3 wk aftertreatment: a susceptible (S) phenotype which was killed, an intermediateresistance (I) phenotype with severe injury, and a resistant (R) phenotypewith little or no injury. Testcross progeny exhibited only I and S phenotypes.Observed segregation of phenotypes in F2 and testcross populations conformedto segregation ratios predicted for a trait with inheritance controlled by asingle partially dominant nuclear gene. ACCase activity determined in crudecell-free extracts of resistant, F1, and susceptible biotypes exhibited I50values of 50, 20, and 0.7 micromolar diclofop, respectively. A positiverelationship between the injury response phenotype and site of action (ACCase)response to diclofop was evident in both F1 and F2 populations. In extractsfrom R, I, and S phenotype F2 plants, 20 micromolar diclofop acid inhibitedACCase-mediated incorporation of 14C by 27.1, 45.1, and 78.9%, respectively.The ACCase data are consistent with the hypothesis that diclofop resistance inItalian ryegrass is conferred by a diclofop-insensitive form of ACCase.
202                                                   NAL Call. No.: 450 J8224Mechanism of isoxaben tolerance in Agrostis palustris var. Penncross.Heim, D.R.; Bjelk, L.A.; James, J.; Schneegurt, M.A.; Larrinua, I.M.Oxford : Oxford University Press; 1993 Jul.Journal of experimental botany v. 264 (44): p. 1185-1189; 1993 Jul.  Includesreferences.
Language:  English
Descriptors: Agrostis stolonifera var. palustris; Arabidopsis thaliana;Isoxaben; Herbicide resistance; Cellulose; Carbohydrate metabolism; Uptake;Binding site; Interactions; Metabolism; Cell wall components
Abstract:  Previous work has demonstrated that isoxaben tolerant mutants ofArabidopsis thaliana var. Columbia are most likely altered at the site ofisoxaben binding. The salient question becomes whether or not speciesselectivity to this herbicide might also be a result of differential targetsite binding. Grasses are generally more tolerant to isoxaben than dicots. Inthis communication we show that Agrostis palustris var. Penncross, a grass, is83-fold more tolerant in a soil incorporation test and 170-fold more tolerantto inhibition of glucose incorporation into cellulose than is Arabidopsis, adicot. Cell wall fractionation of Agrostis shows a specific effect oncellulose biosynthesis. At most, 5-fold of the 170-fold tolerance exhibited byAgrostis in terms of cellulose biosynthesis can be attributed to decreasedisoxaben uptake under the test conditions. Furthermore, Agrostis is unable tometabolize isoxaben to any significant degree. Therefore, we suggest that themajor portion of the tolerance in Agrostis might be due to differences inisoxaben binding.
203                                                     NAL Call. No.: QK1.A57Mechanisms and agronomic aspects of herbicide resistance.Holt, J.S.; Powles, S.B.; Holtum, J.A.M.Palo Alto, Calif. : Annual Reviews, Inc; 1993.Annual review of plant physiology and plant molecular biology v. 44: p.203-209; 1993.  Literature review.  Includes references.
Language:  English
Descriptors: Crops; Herbicide resistance; Herbicide resistant weeds; Reviews;Plant physiology
204                                                    NAL Call. No.: SB249.N6Mechanisms for resistance of weeds to herbicides.Duke, S.O.Memphis, Tenn. : National Cotton Council of America, 1991-; 1993.Proceedings / v. 3: p. 1509-1511; 1993.  Meeting held January 10-14, 1993, NewOrleans, Louisiana.  Includes references.
Language:  English
Descriptors: Weeds; Herbicide resistance
205                                                    NAL Call. No.: 79.9 W52Mechanisms of resistance to acetolactate synthase/acetohydroxyacid synthaseinhibitors.Shaner, D.L.Reno, Nev. : The Society; 1991.Proceedings - Western Society of Weed Science v. 44: p. 122-125; 1991.Meeting held March 12-14, 1991, Seattle Washington.  Includes references.
Language:  English
Descriptors: Herbicide resistance; Herbicides; Mode of action; Enzymeinhibitors; Ligases; Resistance mechanisms
206                                             NAL Call. No.: SB957.R474 1991Mechanisms of resistance to herbicides.Dodge, A.D.London : Published for SCI by Elsevier Applied Science; 1991.Resistance '91, Achievement and Developments in Combating Pesticide Resistance/ edited by Ian Denholm, Alan L. Devonshire, and Derek W. Hollomon. p.203-217; 1991.  Proceedings of the SCI Symposium "Resistance '91: Achievementsand Developments in Combating Pesticide Resistance," 15-17 July 1991,Rothamsted Experimental Station, Harpenden, UK.  Includes references.
Language:  English
Descriptors: Weed control; Herbicide resistance; Metabolism
207                                                    NAL Call. No.: 450 P692Membrane response to diclofop acid is pH dependent and is regulated by theprotonated form of the herbicide in roots of pea and resistant and susceptiblerigid ryegrass.DiTomaso, J.M.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Aug.Plant physiology v. 102 (4): p. 1331-1336; 1993 Aug.  Includes references.
Language:  English
Descriptors: Pisum sativum; Lolium rigidum; Diclofop; Organic acids;Herbicidal properties; Ph; Electrophysiology; Plasma membranes; Membranepotential; Roots; Cell walls; Herbicide resistance; Biotypes
Abstract:  Electrophysiological studies in roots of pea (Pisum sativum L.) andrigid ryegrass (Lolium rigidum Gaud.) seedlings were conducted to elucidatethe mechanism involved in the membrane response to the herbicide diclofop. Inpea, a dicotyledonous plant insensitive to diclofop, membrane depolarizationat varying pH values and herbicide concentrations increased at higherconcentrations of the protonated form of diclofop acid (pKa 3.57). Inunbuffered nutrient solution (pH 5.7), diclofop acid (50 micromolars)depolarized the membrane potential (Em) in roots of both resistant andsusceptible biotypes of rigid ryegrass, whereas recovery of Em occurred onlyin the resistant biotype following removal of the herbicide. This differentialresponse was correlated with an increase (450%) in the rate of acidificationof the external solution by the susceptible biotype, and the Em differencesbetween biotypes were eliminated in solutions buffered at pH 5.0 or 6.0. Inaddition, p-chloromercuribenzene-sulfonic acid did not prevent thedepolarization of Em by 50 micromolars diclofop acid. It is concluded that thedifferential membrane response to diclofop acid in herbicide-resistant and-susceptible biotypes of rigid ryegrass is due to pH differences at the cellwall/plasmalemma interface. Although the membrane response is probably notinvolved in the primary inhibitory effect of diclofop on plant growth, itcould reduce the concentration of the permeant protonated form of theherbicide and possibly could contribute to increased tolerance to diclofop andother weak acid herbicides.
208                                                    NAL Call. No.: 500 N813Metabolism of metribuzin in somaclonal variants of tomato.Breiland, K.; Davis, D.G.; Swanson, H.R.; Frear, D.S.; Secor, G.Grand Forks, N.D. : The Academy; 1991 Apr.Proceedings of the North Dakota Academy of Science v. 45: p. 36; 1991 Apr.Paper presented at the 83rd Annual Meeting, April 25-26, 1991, Minot, NorthDakota.  Includes references.
Language:  English
Descriptors: Lycopersicon esculentum; Somaclonal variation; Cultivars;Herbicide resistance; Metribuzin
209                                                   NAL Call. No.: 381 J8223Metabolism of sulfometuron-methyl in wheat and its possible role in wheatintolerance.Anderson, J.J.; Swain, R.S.Washington, D.C. : American Chemical Society; 1992 Nov.Journal of agricultural and food chemistry v. 40 (11): p. 2279-2283; 1992 Nov. Includes references.
Language:  English
Descriptors: Triticum aestivum; Sulfonylurea herbicides; Metabolism; Metabolicdetoxification; Herbicide resistance
Abstract:  [phenyl-(U)-(14)C]Sulfometuron-methyl was metabolized in excisedwheat (sensitive to sulfometuron-methyl) to [(14)C]methyl2-[[[[(4-(hydroxymethyl)-6-methylpyrimindin-2-yl)amino]carbonyl]amino]sulfonyl]benzoate (HM-SM) and its carbohydrate conjugate. Thismetabolic pathway is consistent with sulfometuron-methyl metabolism intolerant species such as Bermuda grass. Sulfometuron-methyl was metabolized ata slower rate than metsulfuron-methyl in wheat. When plantswere exposed to[(14)C]methyl 4-hydroxy-2-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]amino] sulfonyl]benzoate (HP-MM) and [(14)C]HM-SM the primaryhydroxylated wheat metabolites of metsulfuron-methyl and sulfometuron-methyl,respectively), the rate of glucose conjugation of HP-MM was much faster thanthe rate of glucose conjugation of HM-SM. Along with their parent compounds,both HM-SM and HP-MM are potent inhibitors of wild mustard acetolactatesynthase. These results indicate that wheat intolerance to sulfometuron-methylbut tolerance to the structurally closely related (metsulfuron-methyl)reflects not only a reduced ability to hydroxylate the parent molecule butalso a reduced ability to conjugate the primary toxic metabolite to a nontoxicmoiety.
210                                                   NAL Call. No.: QK710.P55Mode of action of paraquat in leaves of paraquat-resistant Conyza canadensis(L.) Cronq.Lehoczki, E.; Laskay, G.; Gaal, I.; Szigeti, Z.Oxford : Blackwell Scientific Publications; 1992 Jun.Plant, cell and environment v. 15 (5): p. 531-539; 1992 Jun.  Includesreferences.
Language:  English
Descriptors: Conyza canadensis; Paraquat; Herbicidal properties; Herbicideresistance; Herbicide resistant weeds; Biotypes; Phytotoxicity;Photosynthesis; Chlorophyll; Fluorescence; Ethanol production; Oxygen; Gasproduction; Light; Leaves; Light intensity
211                                             NAL Call. No.: SB957.R474 1991Modelling herbicide resistance--a study of ecological fitness.Mortimer, A.M.; Ulf-Hansen, P.F.; Putwain, P.D.London : Published for SCI by Elsevier Applied Science; 1991.Resistance '91, Achievement and Developments in Combating Pesticide Resistance/ edited by Ian Denholm, Alan L. Devonshire, and Derek W. Hollomon. p.148-164; 1991.  Proceedings of the SCI Symposium "Resistance '91: Achievementsand Developments in Combating Pesticide Resistance," 15-17 July 1991,Rothamsted Experimental Station, Harpenden, UK.  Includes references.
Language:  English
Descriptors: Alopecurus myosuroides; Herbicide resistance
212                                                     NAL Call. No.: 472 N42Modified wheat paves the way to bumper harvest.Coghlan, A.London, Eng. : New Science Publications; 1992 Jul27.New scientist v. 134 (1827): p. 19; 1992 Jul27.
Language:  English
Descriptors: Florida; Triticum aestivum; Genetic engineering; Herbicideresistance
213                                    NAL Call. No.: LU378.76 L930d 1991 sathThe molecular basis of imidazolinone herbicide resistance in arabidopsisthalian var. columbia.Sathasivan, Kanagasabapathi,1991; 1991.x, 67 leaves : ill. ; 29 cm.  Vita.  Abstract.  Includes bibliographicalreferences (leaves 60-62).
Language:  English
Descriptors: Plants, Effect of herbicides on; Herbicides; Imidazoline
214                                                    NAL Call. No.: 450 P692Molecular basis of imidazolinone herbicide resistance in Arabidopsis thalianavar Columbia.Sathasivan, K.; Haughn, G.W.; Murai, N.Rockville, Md. : American Society of Plant Physiologists; 1991 Nov.Plant physiology v. 97 (3): p. 1044-1050; 1991 Nov.  Includes references.
Language:  English
Descriptors: Arabidopsis thaliana; Imidazolinone herbicides; Herbicideresistance; Plant breeding; Genetic transformation; Gene transfer; Mutants;Genetic variation
Abstract:  Acetolactate synthase (ALS), the first enzyme in the biosyntheticpathway of leucine, isoleucine, and valine, is inhibited by imidazolinoneherbicides. To understand the molecular basis of imidazolinone resistance, weisolated the ALS gene from an imazapyr-resistant mutant GH90 of Arabidopsisthaliana. DNA sequence analysis of the mutant ALS gene demonstrated asingle-point mutation from G to A at nucleotide 1958 of the ALS-codingsequence. This would result in Ser to Asn substitution at residue 653 near thecarboxyl terminal of the matured ALS. The mutant ALS gene was introduced intotobacco using Agrobacterium-mediated transformation. Imidazolinone-resistantgrowth of transformed calli and leaves of transgenic plants was 100-foldgreater than that of nontransformed control plants. The relative levels ofimidazolinone-resistant ALS activity correlated with the amount ofherbicide-resistant growth in the leaves of transgenic plants. Southernhybridization analysis confirmed the existence of transferred ALS gene in thetransformant showing high imazapyr resistance. The results demonstrate thatthe mutant ALS gene confers resistance to imidazolinone herbicides. This isthe first report, to our knowledge, of the molecular basis of imidazolinoneresistance in plants.
215                                                   NAL Call. No.: QK710.P62The molecular basis of resistance to the herbicide norflurazon.Chamovitz, D.; Pecker, I.; Hirschberg, J.Dordrecht : Kluwer Academic Publishers; 1991 Jun.Plant molecular biology : an international journal on fundamental research andgenetic engineering v. 16 (6): p. 967-974; 1991 Jun.  Includes references.
Language:  English
Descriptors: Synechococcus; Genes; Cloning; Nucleotide sequences; Enzymes;Norflurazon; Herbicide resistance; Amino acid sequences; Models; Plants;Restriction mapping; Mutations
Abstract:  We have cloned and sequenced a gene, pds, from the cyanobacteriumSynechococcus PCC7942 that is responsible for resistance to the bleachingherbicide norflurazon. A point mutation in that gene, leading to an amino acidsubstitution from valine to glycine in its polypeptide product, was found toconfer this resistance. Previous studies with herbicide-resistant mutants haveindicated that this gene encodes phytoene desaturase (PDS), a key enzyme inthe biosynthesis of carotenoids. A short amino acid sequence that ishomologous to conserved motifs in the binding sites for NAD(H) and NADP(H) wasidentified in PDS, suggesting the involvement of these dinucleotides ascofactors in phytoene desaturation.
216                                                   NAL Call. No.: SB610.W39Monitoring the occurrence of sulfonylurea-resistant prickly lettuce (Lactucaserriola).Alcocer-Ruthling, M.; Thill, D.C.; Mallory-Smith, C.Champaign, Ill. : The Society; 1992 Apr.Weed technology : a journal of the Weed Science Society of America v. 6 (2):p. 437-440; 1992 Apr.  Includes references.
Language:  English
Descriptors: Idaho; Lactuca serriola; Herbicide resistant weeds; Sulfonylureaherbicides; Herbicide resistance; Metsulfuron; Sulfometuron; Surveys;Biotypes; Population dynamics
217                                                   NAL Call. No.: 64.8 C883Monogenic dominant sulfonylurea resistance in sugarbeet from somatic cellselection.Saunders, J.W.; Acquaah, G.; Renner, K.A.; Doley, W.P.Madison, Wis. : Crop Science Society of America; 1992 Nov.Crop science v. 32 (6): p. 1357-1360; 1992 Nov.  Includes references.
Language:  English
Descriptors: Beta vulgaris; Herbicide resistance; Chlorsulfuron; Inheritance;Cell culture; Culture media; Somatic mutations; Dominance; Genes; Somaclonalvariation
Abstract:  Injury to sugarbeet, Beta vulgaris L., from sulfonylurea herbicideresidues from preceding cropping years has kindled interest in developingresistant cultivars. This study was conducted to obtain chlorsulfuron(2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide) resistance from cell cultures and to determine itsinheritance and magnitude. Utilizing annual diploid sugarbeet clone REL-1,dispersed suspension cultures were initiated from callus induced on leaf diskscultured on a modified Murashige and Skoog (MS) agar medium + 1.0 mg L-1N6-benzyladenine (BA) and placed in the liquid form of the same medium.Unmutagenized cell clusters were plated on solid medium containing 2.8micromolar chlorsulfuron in MS + 1.0 mg L-1 BA. A single colony arose, fromwhich shoots were regenerated. Shoots were resistant to 28 nM chlorsulfuron, aconcentration that killed similar shoots of REL-1. Resistance (designated Sur)was inherited as a monogenic dominant. In vitro shoot resistance tochlorsulfuron was 300 to 1000-fold greater than in REL-1. Resistance was alsoexpressed in leaf disk expansion in vitro with MS + 1.0 mg L-1 BA.
218                                                   NAL Call. No.: 442.8 Z34Multiple resistance to sulfonylureas and imidazolinones conferred by anacetohydroxyacid synthase gene with separate mutations for selectiveresistance.Hattori, J.; Rutledge, R.; Labbe, H.; Brown, D.; Sunohara, G.; Miki, B.Berlin, W. Ger. : Springer International; 1992 Mar.M G G : Molecular and general genetics v. 232 (2): p. 167-173; 1992 Mar.Includes references.
Language:  English
Descriptors: Arabidopsis thaliana; Nicotiana tabacum; Genetic transformation;Transgenics; Genes; Oxo-acid-lyases; Alleles; Mutants; Herbicide resistance;Chlorsulfuron; Imidazolinone herbicides; Nucleotide sequences; Enzymeactivity; Amino acid sequences; Induced mutations
Abstract:  The acetohydroxyacid synthase (AHAS) gene from the Arabidopsisthaliana mutant line GH90 carrying the imidazolinone resistance allele imr1was cloned. Expression of the AHAS gene under the control of the CaMV 35Spromoter in transgenic tobacco resulted in selective imidazolinone resistance,confirming that the single base-pair change found near the 3' end of thecoding region of this gene is responsible for imidazolinone resistance. Achimeric AHAS gene containing both the imr1 mutation and the csr1 mutation,responsible for selective resistance to sulfonylurea herbicides, wasconstructed. It conferred on transgenic tobacco plants resistance to bothsulfonylurea and imidazolinone herbicides. The data illustrate that amultiple-resistance phenotype can be achieved in an AHAS gene throughcombinations of separate mutations, each of which individually confersresistance to only one class of herbicides.
219                                                     NAL Call. No.: Q11.J68Mutant weeds of Iowa. V. S-triazine resistant Setaria faberi Herrm.Thornhill, R.; Dekker, J.Cedar Falls, Iowa : The Academy; 1993 Mar.The Journal of the Iowa Academy of Science : JIAS v. 100 (1): p. 13-14; 1993Mar.  Includes references.
Language:  English
Descriptors: Iowa; Setaria faberi; Herbicide resistant weeds; Mutants;Triazine herbicides
220                                                    NAL Call. No.: QH301.J6A mutation in the alpha 1-tubulin gene of Chlamydomonas reinhardtii confersresistance to anti-microtubule herbicides.James, S.W.; Silflow, C.D.; Stroom, P.; Lefebvre, P.A.Cambridge : The Company of Biologists Limited; 1993 Sep.Journal of cell science v. 106 (pt.1): p. 209-218; 1993 Sep.  Includesreferences.
Language:  English
Descriptors: Chlamydomonas reinhardtii; Induced mutations; Tubulin; Structuralgenes; Alleles; Gene mapping; Linkage groups; Herbicide resistance;Amiprofos-methyl; Oryzalin; Microtubules; Semidominance; Segregation;Nucleotide sequences
221                                                    NAL Call. No.: 442.8 Z8Mutations in corn (Zea mays L.) conferring resistance to imidazolinoneherbicides.Newhouse, K.; Singh, B.; Shaner, D.; Stidham, M.Berlin, W. Ger. : Springer International; 1991.Theoretical and applied genetics v. 83 (1): p. 65-70; 1991.  Includesreferences.
Language:  English
Descriptors: Zea mays; Induced mutations; Oxo-acid-lyases; Alleles;Semidominant genes; Enzyme activity; Herbicide resistance; Imazethapyr;Imazaquin; Sulfometuron; Inheritance; Crossing; Inbred lines
Abstract:  Three corn (Zea mays L.) lines resistant to imidazolinoneherbicides were developed by in vitro selection and plant regeneration. Forall three lines, resistance is inherited as a single semidominant allele. Theresistance alleles from resistant lines XA17, XI12, and QJ22 have been crossedinto the inbred line B73, and in each case homozygotes are tolerant ofcommercial use rates of imidazolinone herbicides. All resistant selectionshave herbicide-resistant forms of acetohydroxyacid synthase (AHAS), the knownsite of action of imidazolinone herbicides. The herbicide-resistant phenotypesdisplayed at the whole plant level correlate directly with herbicideinsensitivity of the AHAS activities of the selections. The AHAS activitiesfrom all three selections have normal feedback regulation by valine andleucine, and plants containing the mutations display a normal phenotype.
222                                                     NAL Call. No.: 450 N42Natural tolerance of cyanobacteria to the herbicide glyphosate.Powell, H.A.; Kerby, N.W.; Rowell, P.Cambridge : Cambridge University Press; 1991 Nov.The New phytologist v. 119 (3): p. 421-426; 1991 Nov.  Includes references.
Language:  English
Descriptors: Anabaena variabilis; Glyphosate; Phytotoxicity; Herbicideresistance
223                                             NAL Call. No.: SB957.R474 1991The needs for new herbicide-resistant crops.Gressel, J.London : Published for SCI by Elsevier Applied Science; 1991.Resistance '91, Achievement and Developments in Combating Pesticide Resistance/ edited by Ian Denholm, Alan L. Devonshire, and Derek W. Hollomon. p.283-294; 1991.  Proceedings of the SCI Symposium "Resistance '91: Achievementsand Developments in Combating Pesticide Resistance," 15-17 July 1991,Rothamsted Experimental Station, Harpenden, UK.  Includes references.
Language:  English
Descriptors: Plant breeding; Genetic resistance; Herbicide resistance
224                                                   NAL Call. No.: SB951.P47Negative cross-resistance to bentazone and pyridate in atrazine-resistantAmaranthus cruentus and Amaranthus hybridus biotypes.Prado, R. de; Sanchez, M.; Jorrin, J.; Dominguez, C.Essex : Elsevier Applied Science Publishers; 1992.Pesticide science v. 35 (2): p. 131-136; 1992.  Includes references.
Language:  English
Descriptors: Spain; Amaranthus cruentus; Amaranthus hybridus; Herbicideresistance; Cross resistance; Atrazine; Cyanazine; Acetochlor; Alachlor;Bentazone; Propachlor; Pyridate; Mcpa; Phytotoxicity; Photosynthesis;Inhibition; Chloroplasts; Chlorophyll
Abstract:  Plants of Amaranthus cruentus and Amaranthus hybridus resistant toatrazine and cyanazine were found in maize fields in north-eastern Spain. Bothresistant biotypes survived doses of 5 kg ha-1 of atrazine and 2-4 kg ha-1 ofcyanazine but were controlled by lower doses of bentazone and pyridate thanwere susceptible biotypes. Such a negative cross-resistance was not found forchloroacetamides and MCPA. Chlorophyll fluorescence studies revealed thatatrazine, bentazone, cyanazine and pyridate (10 mg litre-1) caused inhibitionof photosynthetic electron transport in susceptible leaves, while in resistantplants, atrazine and cyanazine had no effect. Conversely, bentazone andpyridate inhibited photosynthesis to a greater extent in resistant than insusceptible biotypes. Isolated chloroplast membranes from resistant biotypesshowed resistance factors of 366 and 501 to atrazine and 39 and 60 tocyanazine for A. hybridus and A. cruentus, respectively. Bentazone andpyridate were found to be more effective in chloroplasts of the resistantbiotypes than those of the susceptible plants. It is suggested that enhancedsusceptibility to bentazone and pyridate in triazine-resistant A. cruentus and-  hybridus biotypes may be associated with the alteration of the D-1polypeptide subunit of photosystem II, as found in triazine-resistant plants.  225                                                 NAL Call. No.: SB610.2.B74Nitrodiphenyl ether and phenylimide resistance of a tobacco biotype is due toenhanced inducibility of its antioxidant systems.Gullner, G.; Kiraly, L.; Komives, T.Surrey : BCPC Registered Office; 1991.Brighton Crop Protection Conference-Weeds v. 3: p. 1111-1118; 1991.  Meetingheld November 18-21, 1991, Brighton, England.  Includes references.
Language:  English
Descriptors: Nicotiana; Antioxidants; Biotypes; Herbicide resistance
226                                                   NAL Call. No.: SB951.P49A novel pattern of herbicide cross-resistance in a trifluralin-resistantbiotype of green foxtail [Setaria viridis (L.) Beauv.].Smeda, R.J.; Vaughn, K.C.; Morrison, I.N.Orlando, Fla. : Academic Press; 1992 Mar.Pesticide biochemistry and physiology v. 42 (3): p. 227-241; 1992 Mar.Includes references.
Language:  English
Descriptors: Manitoba; Setaria viridis; Biotypes; Herbicide resistance;Herbicide resistant weeds; Cross resistance; Trifluralin; Herbicides;Dinitroaniline herbicides; Resistance mechanisms; Propyzamide; Terbucarb;Amiprofos-methyl; Propham; Chlorthal-dimethyl; Barban; Chlorpropham
Abstract:  A trifluralin-resistant (R) biotype of Setaria viridis is found inareas of Manitoba, Canada where trifluralin is utilized its the principal orsole herbicide. In this study, we examine the cross-resistance pattern of thisbiotype to other mitotic disrupter herbicides utilizing growth measurementsand electron microscopy to monitor the resistance. Compared to atrifluralin-susceptible (S) biotype, the R biotype is cross-resistant to alldinitroaniline herbicides tested, with I50 R/S ratios [the concentration ofherbicide required to inhibit root growth of the R biotype by 50% divided bythe concentration which induces the same effect for the S biotype] rangingfrom 1.6 to 14.8. This R biotype is also cross-resistant at about the samelevel to amiprophosmethyl and dithiopyr, but exhibits no resistance topronamide, sindone B, barban, or the microtubule stabilizer taxol. The highestlevel of resistance is to the structurally unrelated herbicides DCPA (I50, R/S> 50) and terbutol (I50 R/S = 13.4). This is the first reported incidence ofresistance to these two herbicides. Ultrastructural observations showherbicide-induced abnormalities are either reduced or absent in the R biotype.The S biotype is actually less susceptible to chlorpropham and propham (R/SI50) = 0.7) than the R biotype. The high level of resistance to thephragmoplast-disrupting microtubule herbicide DCPA, as well as terbutol, and alower level of resistance to a number of other tubulin-interacting microtubuledisrupters, indicate that the R biotype may contain an alteration in acytoskeletal protein that stabilizes phragmoplast microtubule arrays.
227                                                   NAL Call. No.: QD435.D57Nucleotide sequence of a 2kb plasmid from Pseudomonas cepacia implicated inthe degradation of phenylcarbamate herbicides.Gaubier, P.; Vega, D.; Cooke, R.Chur ; New York : Harwood Academic Publishers, 1990-; 1992.DNA sequence : the journal of DNA sequencing and mapping v. 2 (4): p. 269-271;1992.  Includes references.
Language:  English
Descriptors: Pseudomonas cepacia; Plasmids; Nucleotide sequences; Herbicideresistance; Carbamate herbicides; Microbial degradation; Amino acid sequences
Abstract:  The complete nucleotide sequence of a very small plasmid whosepresence and level in Pseudomonas cepacia have been linked to herbicideresistance is presented. The structural features of the plasmid are discussed.
228                                                   NAL Call. No.: QK710.P62Nucleotide sequence of the phytoene desaturase gene from Synechocystis sp. PCC6803 and characterization of a new mutation which confers resistance to theherbicide norflurazon.Martinez-Ferez, I.M.; Vioque, A.Dordrecht : Kluwer Academic Publishers; 1992 Mar.Plant molecular biology : an international journal on molecular biology,biochemistry and genetic engineering v. 18 (5): p. 981-983; 1992 Mar.Includes references.
Language:  English
Descriptors: Cyanobacteria; Genes; Enzymes; Nucleotide sequences; Mutations;Herbicide resistance; Norflurazon; Amino acid sequences
229                                                    NAL Call. No.: 450 P692On the mechanism of resistance to paraquat in Hordeum glaucum and H.leporinum: Delayed inhibition of photosynthetic O2 evolution after paraquatapplication.Preston, C.; Holtum, J.A.M.; Powles, S.B.Rockville, MD : American Society of Plant Physiologists, 1926-; 1992 Oct.Plant physiology v. 100 (2): p. 630-636; 1992 Oct.  Includes references.
Language:  English
Descriptors: Hordeum glaucum; Hordeum murinum subsp. leporinum; Paraquat;Herbicide resistance; Herbicide resistant weeds; Photosynthesis; Oxygen; Gasproduction; Biotypes; Translocation; Leaves; Diquat
Abstract:  The mechanism of resistance to paraquat was investigated inbiotypes of Hordeum glaucum Steud. and H. leporinum Link. with high levels ofresistance. Inhibition of photosynthetic O2 evolution after herbicideapplication was used to monitor the presence of paraquat at the active site.Inhibition of photosynthetic O2 evolution after paraquat application wasdelayed in both resistant biotypes compared with the susceptible biotypes;however, this differential was more pronounced in the case of H. glaucum thanin H. leporinum. Similar results could be obtained with the related herbicidediquat. Examination of the concentration dependence of paraquat-inducedinhibition of evolution showed that the resistant H. glaucum biotype was lessaffected by herbicide compared with the susceptible biotype 3 h aftertreatment at most rates. The resistant H. leporinum biotype, in contrast, wasas inhibited as the susceptible biotype except at the higher rates. In allcases photosynthetic evolution was dramatically inhibited 24 h aftertreatment. Measurement of the amount of paraquat transported to the youngtissue of these plants 24 h after treatment showed 57% and 53% reductions inthe amount of herbicide transported in the case of the resistant H. glaucumand H. leporinum biotypes, respectively, compared with the susceptiblebiotypes. This was associated with 62% and 66% decreases in photosyntheticevolution of young leaves in the susceptible H. glaucum and H. leporinumbiotypes, respectively, a 39% decrease in activity for the resistant H.leporinum biotype, but no change in the resistant H. glaucum biotype.Photosynthetic evolution of leaf slices from resistant H. glaucum was not asinhibited by paraquat compared with the susceptible biotype; however, those ofresistant and susceptible biotypes of H. leporinum were equally inhibited byparaquat. Paraquat resistance in these two biotypes appears to be aconsequence of reduced movement of the herbicide in the resistant plants;however, the mechanism involved is not the same in H. glaucum as in H.leporinum.
230                                                    NAL Call. No.: 442.8 Z8The origin and evolution of weed beets: consequences for the breeding andrelease of herbicide-resistant transgenic sugar beets.Boudry, P.; Morchen, M.; Saumitou-Laprade, P.; Vernet, P.; Van Dijk, H.Berlin, W. Ger. : Springer International; 1993 Dec.Theoretical and applied genetics v. 87 (4): p. 477-478; 1993 Dec.  Includesreferences.
Language:  English
Descriptors: France; Cabt; Beta vulgaris; Beta vulgaris var. saccharifera;Weeds; Biotypes; Evolution; Mitochondrial  DNA; Chloroplasts; Dna; Restrictionfragment length polymorphism; Annual habit; Alleles; Dominance; Pollination;Hybridization; Cultivars; Life cycle; Weed biology; Maternal effects;Chloroplast genetics; Genotypes; Mitochondrial genetics; Cytoplasmic malesterility
Abstract:  Populations of weed beets have expanded into European sugar beetproduction areas since the 1970s, thereby forming a serious new weed problemfor this crop. We sampled seeds in different French populations and studiedmitochondrial DNA, chloroplast DNA and life-cycle variability. Given thematernal inheritance of the mitochondrial and chloroplastic genomes and thenuclear determinism of the annual habit, we were able to determine thematernal origin and evolution of these weed beet populations. Our study showsthat they carry the dominant allele "B" for annual habit at high frequency.The main cytoplasmic DNA type found in northern weed beet populations is thecytoplasmic male-sterile type characteristic of sugar beets. We were able todetermine that these populations arise from seeds originating from theaccidental pollinations of cultivated beets by adventitious beets in the seedproduction area, which have been transported to the regions where sugar beetsare cultivated. These seeds are supposedly the origin of the weed forms and afrequently disturbed cultivated environment has selected for annual habit andearly flowering genotypes. We discuss the consequences of the weed beetpopulations for the breeding, seed production and release ofherbicide-resistant transgenic sugar beets.
231                                                      NAL Call. No.: SB1.H6Ornamental grass tolerance to postemergence grass herbicides.Hubbard, J.; Whitwell, T.Alexandria, Va. : The American Society for Horticultural Science; 1991 Dec.HortScience : a publication of the American Society for Horticultural Sciencev. 26 (12): p. 1507-1509; 1991 Dec.  Includes references.
Language:  English
Descriptors: Grasses; Ornamental herbaceous plants; Herbicide resistance;Calamagrostis; Cortaderia; Eragrostis; Erianthus; Miscanthus; Sorghastrum;Spartina; Panicum; Sethoxydim; Fenoxaprop; Fluazifop-p; Phytotoxicity;Application rates; Abiotic injuries
Abstract:  Twelve ornamental grasses from the genera Calamagrostis,Cortaderia, Eragrostis, Erianthus, Miscanthus, Sorghastrum, Spartina, Panicum,and Pennisetum were evaluated for tolerance to the postemergence herbicidesfenoxaprop-ethyl, fluazifop-P, and sethoxydim at 0.4 kg a.i./ha. Calamagrostiswas uninjured by fenoxaprop-ethyl as measured by visual injury ratings,height, and foliage dry weight. Greenhouse studies evaluated the tolerance ofthree Calamagrostis cultivars to fenoxaprop-ethyl rates of 0.4 to 3.2 kga.i./ha with no observed visual injury from any treatment. However, theexpansion rate of the youngest Calamagrostis leaf was reduced linearly withincreasing herbicide rates each day after application. The highest rate (3.2kg a.i./ha) reduced the leaf expansion rate by 1 day and all other rates by 3days after treatment. Leaf expansion rate differed between Calamagrostiscultivars at different times after herbicide treatment. Dry weight ofCalamagrostis arundinacea 'Karl Foerster' was reduced at 4 weeks aftertreatment but not at 10 weeks after treatment.
232                                                   NAL Call. No.: 442.8 Z34Overproduction by gene amplification of the multifunctional arom proteinconfers glyphosate tolerance to a plastid-free mutant of Euglena gracilis.Reinbothe, S.; Ortel, B.; Parthier, B.Berlin, W. Ger. : Springer International; 1993 Jun.Molecular & general genetics : MGG v. 239 (3): p. 416-424; 1993 Jun.  Includesreferences.
Language:  English
Descriptors: Euglena gracilis; Amplification; Genes; Plant proteins;Glyphosate; Herbicide resistance; Enzyme activity; Alkyl (aryl) transferases;Alcohol oxidoreductases; Kinases; Messenger  RNA; Plastids; Mutants; Aminoacid metabolism; Amino acids
Abstract:  Cells of the plastid-free mutant line of Euglena gracilis var.bacillaris, W10BSmL, can be adapted to glyphosate [N-(phosphonomethyl)glycine]by gradually increasing the concentration of the herbicide in the culturemedium. The molecular basis of glyphosate tolerance is the selective ca.ten-fold overproduction of the multifunctional arom protein catalyzing steps2-6 in the pre-chorismate pathway. Determination of 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase (E.C.2.5.1.19), shikimate:NADP+oxidoreductase (E.C.1.1.1.25) and shikimate kinase (E.C.2.7.1.71) activitiesafter non-denaturing gel electrophoresis, in combination with two-dimensionalseparations, revealed an increase in all three enzyme activities associatedwith overproduction of a 165 kDa protein in cells adapted to 6 mM glyphosate.Further evidence for an involvement of the multifunctional arom protein inaromatic amino acid synthesis in the plastid-free W10BSmL cells was obtainedby Northern hybridization with ARO1-, aroA-, aroL- and aroE-specificSaccharomyces cerevisiae gene probes encoding the entire arom protein or partsof the EPSP synthase, shikimate: NADP+ oxidoreductase and shikimate kinasedomains, respectively. Overproduction in adapted relative to control cells ofa 5.3 kb transcript that cross-hybridized with all of the different probescould be demonstrated. The elevated content of the arom transcript correlatedwith a selective amplification of two out of five genomic sequences thathybridized with the S. cerevisiae ARO1 gene probe in Southern blots. One ofthe amplified genomic fragments is assumed to encode the previously identifiedmonofunctional 59 kDa EPSP synthase, which is thought to be an organellarprotein, that accumulates to a certain extent in its enzymatically activeprecursor form of 64.5 kDa in the plastid-free W10BSmL cells.
233                                                    NAL Call. No.: 450 P692Overproduction of gamma-linolenic and eicosapentaenoic acids by algae.Cohen, Z.; Didi, S.; Heimer, Y.M.Rockville, Md. : American Society of Plant Physiologists; 1992 Feb.Plant physiology v. 98 (2): p. 569-572; 1992 Feb.  Includes references.
Language:  English
Descriptors: Spirulina; Algae; Biosynthesis; Linolenic acid; Eicosapentaenoicacid; Genetic regulation; Cell lines; Herbicide resistance; Plant breeding;Selection; High yielding varieties
Abstract:  The pharmaceutical interest and limited availability ofgamma-linolenic acid (GLA) and eicosapentaenoic acid (EPA) prompted the searchfor genetic means for increasing the production of these fatty acids fromalgal sources. Cell lines of Spirulina platensis and Porphyridium cruentumresistant to the growth inhibition of the herbicide Sandoz 9785 were selectedby serial transfers of the culture in the presence of increasingconcentrations of the herbicide. The resistant cell lines of S. platensisoverproduced GLA and those of P. cruentum overproduced EPA and were stable forat least 50 generations in the absence of the inhibitor.
234                                                    NAL Call. No.: 100 L939Overtop applications of Buctril controls broadleaf weeds in transgenic cotton.Crawford, S.H.Baton Rouge, La. : The Station; 1993.Louisiana agriculture - Louisiana Agricultural Experiment Station v. 36 (1):p. 23; 1993.
Language:  English
Descriptors: Louisiana; Gossypium hirsutum; Weed control; Bromoxynil;Transgenics; Herbicide resistance; Field tests
235                                                  NAL Call. No.: SB950.A1P3Oxyflurofen tolerance and weed control in young papaya.Nishimoto, R.K.London : Taylor & Francis Ltd., 1993-; 1993 Jul.International journal of pest management v. 39 (3): p. 366-369; 1993 Jul.Includes references.
Language:  English
Descriptors: Hawaii; Cabt; Carica papaya; Herbicide resistance; Age of trees;Plant height; Susceptibility; Chemical control; Weed control; Bidens pilosa;Oxyfluorfen; Phytotoxicity; Abiotic injuries
236                                                   NAL Call. No.: SB951.P49Paraquat resistance and its inheritance in seed germination of thefoliar-resistant biotypes of Erigeron canadensis L. and E. sumatrensis Retz.Yamasue, Y.; Kamiyama, K.; Hanioka, Y.; Kusanagi, T.Orlando, Fla. : Academic Press; 1992 Sep.Pesticide biochemistry and physiology v. 44 (1): p. 21-27; 1992 Sep.  Includesreferences.
Language:  English
Descriptors: Erigeron sumatrensis; Conyza canadensis; Biotypes; Herbicideresistant weeds; Paraquat; Herbicide resistance; Inheritance; Seedgermination; Foliar application; Genes; Pharmacokinetics
Abstract:  Seeds of the foliar-resistant biotypes of Erigeron canadensis L.and E. sumatrensis Retz. to paraquat (1,1'-dimethyl-4,4'-bipyridinium ion)were studied with respect to resistance at germination. Thresholdconcentrations of the herbicide in foliar susceptibility of seedlings were10(-4) and 10(-6) M for the resistant and susceptible biotypes of E.canadensis, respectively. The concentrations in seed susceptibility atgermination were 10(-5) and 10(-7) M for the respective biotypes. Seeds of theresistant biotype of E. sumatrensis showed less resistance at seed germinationthan those of E. canadensis. The resistant and susceptible biotypes of E.canadensis were reciprocally crossed to make a comparison in inheritancebetween the foliar resistance and seed resistance at germination. In the F2generation, the ratios of foliar-resistant and susceptible seedlings at 10(-5)M fitted well to a 3:1 ratio, indicating that the resistance was controlled bya single nuclear gene. In seed resistance, three-fourths of the F2 seeds wereresistant at 10(-5) M, suggesting that a single gene also controlled theresistance. These results suggested the possibility that a common mechanism ofparaquat resistance exists between the photosynthetic and nonphotosyntheticorgans.
237                                                   NAL Call. No.: QK725.P54Paraquat tolerance in a photomixotrophic culture of Chenopodium rubrum.Bhargava, S.Berlin, W. Ger. : Springer International; 1993.Plant cell reports v. 12 (4): p. 230-232; 1993.  Includes references.
Language:  English
Descriptors: Chenopodium rubrum; Cell cultures; Paraquat; Herbicideresistance; Weed biology; Growth; Chemical composition; Chlorophyll;Photosystem i; Enzyme activity; Superoxide dismutase; Peroxidase; Catalase;Lines; Genetic variation; Metabolic detoxification
Abstract:  A paraquat tolerant line of Chenopodium rubrum has been comparedwith paraquat susceptible cultures, in terms of growth, chlorophyll content,photosystem I partial reactions, and the activities of some enzymes involvedin detoxification of harmful oxygen radicals. Results indicate that paraquattolerance is manifested through increased activity of superoxide dismutase,peroxidase and catalase, in the tolerant line, only in the presence ofparaquat. The behaviour of the paraquat tolerant and susceptible cultures inthe absence of paraquat is quite similar.
238                                                    NAL Call. No.: 79.8 W41Photoacoustic spectroscopy as a tool for monitoring herbicide effects ontriazine-resistant and -susceptible biotypes of black nightshade (Solanumnigrum).Fuks, B.; Homble, F.; Van Eycken, F.; Figeys, H.; Lannoye, R.L.Champaign, Ill. : Weed Science Society of America; 1992 Jul.Weed science v. 40 (3): p. 371-377; 1992 Jul.  Includes references.
Language:  English
Descriptors: Solanum nigrum; Biotypes; Herbicide resistant weeds; Atrazine;Diuron; Herbicide resistance; Detection; Monitoring; Spectroscopy;Photosynthesis
Abstract:  Photoacoustic spectroscopy was used to study effects of atrazineand diuron on excised leaves of triazine-susceptible (S) and -resistant (R)biotypes of black nightshade. Changes of oxygen and photothermal componentswere compared to photochemical fluorescence quenching obtained by fluorimetry.After 1 h incubation in an aqueous solution of atrazine (0 to 200 micromole),oxygen component of the photoacoustic signal was strongly decreased in the Sbiotype while the R biotype was not affected. Also, reoxidation of the primaryquinone acceptor (QA(-1)) of photosystem (PS) II of the S biotype was lowerthan that of the R biotype. With diuron treatments, changes in thecharacteristics of these biophysical signals were the same in both R and Sbiotypes. Both oxygen component and photochemical fluorescence quenching weredecreased in treated leaves of the R and S biotypes. By using modulated oxygenand heat emissions, and the ratio of the initial inflection point (I) to thefluorescence maximum (P) as herbicide bioassay indicators, we showed that thephotoacoustic spectroscopy was also a reliable technique for whole plantstudies. Inhibition of photosynthesis was maximal 2 d after onset of treatmentwith atrazine (200 micromole). Inhibitors of PSII did not induce a significantincrease of heat emission in leaves which otherwise showed phytotoxic symptomsafter treatment. By using the photoacoustic technique, it was possible toobtain useful information on photosynthetic activity under herbicide stress,suggesting that pulsed oxygen emitted by leaves could be used to quantifysusceptibility or to detect resistance to many types of photosyntheticinhibitors in weeds and crop plants.
239                                                    NAL Call. No.: 450 P692Physiological basis for differential sensitivities of plant species toprotoporphyrinogen oxidase-inhibiting herbicides.Sherman, T.D.; Becerril, J.M.; Matsumoto, H.; Duke, M.V.; Jacobs, J.M.;Jacobs, N.J.; Duke, S.O.Rockville, Md. : American Society of Plant Physiologists; 1991 Sep.Plant physiology v. 97 (1): p. 280-287; 1991 Sep.  Includes references.
Language:  English
Descriptors: Abutilon theophrasti; Cucumis sativus; Brassica hirta;Chenopodium album; Amaranthus retroflexus; Medicago sativa; Fagopyrumtataricum; Ipomoea lacunosa; Cassia obtusifolia; Datura stramonium; Spinaciaoleracea; Herbicide resistance; Porphyrins; Biosynthesis; Acifluorfen;Phytotoxicity; Weed control; Herbicidal properties
Abstract:  With a leaf disc assay, 11 species were tested for effects of theherbicide acifluorfen on porphyrin accumulation in darkness and subsequentelectrolyte leakage and photobleaching of chlorophyll after exposure to light.Protoporphyrin IX (Proto IX) was the only porphyrin that was substantiallyincreased by the herbicide in any of the species. However, there was a widerange in the amount of Proto IX accumulation caused by 0.1 millimolaracifluorfen between species. Within species, there was a reduced effect of theherbicide in older tissues. Therefore, direct quantitative comparisons betweenspecies are difficult. Nevertheless, when data from different species and fromtissues of different age within a species were plotted, there was acurvilinear relationship between the amount of Proto IX caused to accumulateduring 20 hours of darkness and the amount of electrolyte leakage orchlorophyll photobleaching caused after 6 and 24 hours of light respectively,following the dark period. Herbicidal damage plateaued at about 10 nanomolesof Proto IX per gram of fresh weight. Little difference was found between invitro acifluorfen inhibition of protoporphyrinogen oxidase (Protox) of plastidpreparations of mustard, cucumber, and morning glory, three species with largedifferences in their susceptibility at the tissue level. Mustard, a highlytolerant species, produced little Proto IX in response to the herbicide,despite having a highly susceptible Protox. Acifluorfen blocked carbon flowfrom delta-aminolevulinic acid to protochlorophyllide in mustard, indicatingthat it inhibits Protox in vivo. Increasing delta-aminolevulinic acidconcentrations (33-333 micromolar) supplied to mustard with 0.1 millimolaracifluorfen increased Proto IX accumulation and herbicidal activity,demonstrating that mustard sensitivity to Proto IX was similar to otherspecies. Differential susceptibility to acifluorfen of the species examined inthis study appears to be due in large part to differences in Proto IXaccumulation in response to the herbicide.  In some cases, differences inProto IX accumlation appear to be due to differences in activity of theporphyrin pathway.
240                                                    NAL Call. No.: 79.8 W41Phytoene desaturase, the essential target for bleaching herbicides.Sandmann, G.; Schmidt, A.; Linden, H.; Boger, P.Champaign, Ill. : Weed Science Society of America; 1991 Jul.Weed science v. 39 (3): p. 474-479; 1991 Jul.  Paper presented at the"Symposium on Herbicide Mechanism of Action," February 7, 1990, Montreal,Canada.  Includes references.
Language:  English
Descriptors: Fluridone; Norflurazon; Flurtamone; Herbicides; Mode of action;Herbicidal properties; Enzyme inhibitors; Phytoene; Biosynthesis; Biochemicalpathways; Herbicide resistance; Molecular genetics; Genes; Cyanobacteria;Cloning; Mutants
Abstract:  Many bleaching herbicides with different core structures inhibitphytoene desaturase (PD), a membrane-bound enzyme in the carotenogenic pathwaycatalyzing the hydrogen abstraction step at the first C40 precursor ofbeta-carotene. Prospects are good that new PD-active herbicides will bediscovered by screening for bleaching activity. Accordingly, interest in PDenzymology and molecular genetics has increased. Although active carotenogeniccell-free systems are available, no isolation of PD has been achieved sincethe enzyme cannot be detected in its isolated form due to complete loss ofactivity. A portion of the Rhodobacter PD gene was incorporated into anappropriate plasmid which could be expressed in E. coli. This system was usedto produce an antibody specific against PD from higher plants as well asRhodobacter. All PDs assayed had an apparent molecular weight of 52 to 55 kDa.A Rhodobacter gene probe hybridized with a 3.1 kbBamHI fragment fromAphanocapsa which allowed us to sequence the PD gene from this cyanobacterium.Its DNA sequence matched with the apparent molecular weight of the PD band inthe western blot, and a fusion-gene product was found to be immunoreactivewith the Rhodobacter PD antibody, Anacystis mutants were produced exhibitingcross-resistance against nornurazon and fluorochloridone. Apparently, thisresistance is due to an altered PD with concurrent decrease of inhibitorbinding affinity. Cloning of the resistant gene into the wild type is inprogress.
241                                                    NAL Call. No.: 79.8 W41Plant cell and tissue culture techniques for weed science research.Smeda, R.J.; Weller, S.C.Champaign, Ill. : Weed Science Society of America; 1991 Jul.Weed science v. 39 (3): p. 497-504; 1991 Jul.  Paper presented at the"Symposium on New Techniques adn Advances in Weed Physiology and MolecularBiology," February 6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Weeds; Weed biology; Laboratory methods; Tissue culture; Cellculture; Screening; Herbicide resistance; Metabolism; Herbicides; Mode ofaction; Uptake; Translocation; In vitro selection
Abstract:  Tissue and cell culture offer weed scientists many opportunities toresearch herbicide effects on plants. This review will discuss examples inwhich plant cells grown in vitro have been used to study herbicide action.Plant cell and tissue culture have many advantages over the use of wholeplants; however, several disadvantages that exist are discussed. Cell culturescan be established for most plant species and provide a relatively homogeneoussystem for studying herbicide action. Responses of plant cells to herbicidesare usually correlated with responses at the whole plant level, and cells havethe advantage of posing fewer physical barriers to herbicide uptake andtranslocation. Cell culture techniques discussed include: screening candidateherbicide compounds; investigating herbicide efficacy, mechanism of action,metabolism, and uptake; and ascertaining mechanisms of herbicide resistance,selecting for resistance, and regenerating crops.
242                                                   NAL Call. No.: QK725.P54A plant selectable marker gene based on the detoxification of the herbicidedalapon.Buchanan-Wollaston, V.; Snape, A.; Cannon, F.Berlin, W. Ger. : Springer International; 1992.Plant cell reports v. 11 (12): p. 627-631; 1992.  Includes references.
Language:  English
Descriptors: Nicotiana plumbaginifolia; Leaves; Agrobacterium tumefaciens;Genetic transformation; Gene transfer; Marker genes; Selective breeding;Dalapon; Herbicide resistance; Phytotoxicity; Enzymes; Degradation; Plasmids;Pseudomonas putida
Abstract:  A gene from Pseudomonas putida coding for a dehalogenase capable ofdegrading 2,2 dichloropropionic acid (2,2DCPA). the active ingredient of theherbicide dalapon, has been isolated and characterised. In planttransformation experiments the gene was shown to confer resistance to 2,2DCPAat a tissue culture level where 2,2DCPA could be used to select fortransformants. At the whole plant level, transformed plants showed resistanceto 2,2DCPA at concentrations up to 5 times the recommended dose rate ofdalapon when it was sprayed on their leaves. At lower concentrations, theherbicide caused a non-lethal yellowing of sensitive plants which clearlydistinguished them from resistant plants. The mode of action of chlorinatedaliphatic acids is not known but they probably affect many enzyme pathways.The results described here are the first example of engineering a plantresistant to a herbicide that does not have one specific enzyme as its targetsite. This gene has several advantages as a marker in plant breeding andgenetic studies. For example, the herbicide is readily available and has lowtoxicity, transformants can be selected at both the tissue culture and thewhole plant level, a large number of transformed plants can easily be screenedeven in the field, and there is a very low probability of selectingspontaneous mutants.
243                                                    NAL Call. No.: 450 P692Pleiotropy in triazine-resistant Brassica napus. Ontogenetic and diurnalinfluences on photosynthesis.Dekker, J.H.; Burmester, R.G.Rockville, MD : American Society of Plant Physiologists, 1926-; 1992 Dec.Plant physiology v. 100 (4): p. 2052-2058; 1992 Dec.  Includes references.
Language:  English
Descriptors: Brassica napus; Pleiotropy; Mutations; Structural genes;Herbicide resistance; Triazine herbicides; Photosynthesis; Chloroplastgenetics; Diurnal variation; Crop growth stage; Biotypes
Abstract:  Studies were conducted that supported the hypothesis that themutation to the psbA plastid gene that confers S-triazine resistance (R) inBrassica napus also results in an altered diurnal pattern of photosyntheticcarbon assimilation (A) relative to that of the susceptible (S) wild type, andthat these patterns change over the ontogeny of a plant. Photosynthetic photonflux density, under closely controlled environmental conditions, wasincrementally increased and decreased on either side of the midday maxima of1150 to 1300 micromoles quanta m-2 s-1. In all experiments, A approximatelytracked the increasing and decreasing diurnal light levels. Younger (3- to4-leaf) R plants had greater photosynthetic rates early and late in thediurnal light period, whereas those of S plants were greater during midday aswell as during the photoperiod as a whole. These relative photosyntheticcharacteristics of R and S plants changed in several ways with ontogeny. Asthe plants aged during the vegetative phase of development, S plants graduallyassimilated more carbon in the early, and then in the late, part of the day.At the end of the vegetative phase of development, R plant carbon assimilationwas less relative to S plants at most times of the day, and was never greater.This relationship between the two biotypes dramatically changed with the onsetof the reproductive phase (8 1/2 to 9 1/2 leaf) of plant development: R plantsassimilated more carbon than S plants during all periods of the diurnal lightperiod with the exception of the late part of the day. In addition to thesedifferences in A, R plant stomatal function differed from that in S plants. Rplant leaves were always cooler than S plant leaves under the sameenvironmental and diurnal conditions. Correlated with this difference in leaftemperature were equal or greater total conductances to water vapor andintercellular CO2 partial pressures in R compared to S leaves in mostinstances. These studies indicate a more complex pattern of photosyntheticcarbon assimilation than previously observed. The photosynthetic superiorityof one biotype relative to the other was a function of the time of day and theage of the plant. These studies also suggest that R plants may have anadaptive advantage over S plants in certain unfavorable ecological nichesindependent of the presence of S-triazine herbicides, such as cool, low-lightenvironments early and late in the day, as well as late in the plants'development. This advantage could result in R biotypes appearing inpopulations of a species in greater numbers than plastidic mutation alonecould cause.
244                                                    NAL Call. No.: 450 P692Pollen expression of herbicide target site resistance genes in annual ryegrass(Lolium rigidum).Richter, J.; Powles, S.B.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Jul.Plant physiology v. 102(3): p. 1037-1041; 1993 Jul.  Includes references.
Language:  English
Descriptors: Lolium rigidum; Herbicide resistant weeds; Herbicide resistance;Sulfometuron; Triasulfuron; Imazapyr; Diclofop; Haloxyfop; Sethoxydim; Pollen;Screening; Gene expression; Structural genes; Oxo-acid-lyases; Acetyl-coacarboxylase; Bitypes; Pollen germination
Abstract:  Herbicide resistance can occur either through target-siteinsensitivity or by nontarget site-based mechanisms. Two herbicide-resistantbiotypes of Lolium rigidum Gaud., one resistant to acetolactate synthase(ALS)-inhibiting herbicides (biotype WLR1) and the other resistant to acetylCoA carboxylase (ACCase)-inhibiting herbicides (biotype WLR96) throughtarget-site insensitivity at the whole plant and enzymic levels, were found toexpress this resistance in the pollen. Pollen produced by resistant biotypesgrew uninhibited when challenged with herbicide, whereas that from asusceptible biotype was inhibited. A third biotype, SLR31, resistant toACCase-inhibiting and certain ALS-inhibiting herbicides at the whole plantlevel through nontarget site-based mechanisms, did not exhibit this expressionin the pollen. The technique described may form the basis for a rapid screenfor certain nuclear-encoded, target site-based herbicide-resistancemechanisms.
245                                                  NAL Call. No.: SB317.5.H6Potential benefits and risks of herbicide-resistant crops produced bybiotechnology.Dyer, W.E.; Hess, F.D.; Holt, J.S.; Duke, S.O.New York, NY : John Wiley & Sons, Inc. Press; 1993.Horticultural reviews v. 15: p. 367-408; 1993.  Includes references.
Language:  English
Descriptors: Herbicide resistance; Crops; Biotechnology; Detoxification;Selection; Screening; Hybridization; Gene transfer; Environmental protection;Economic impact; Reviews
246                                                    NAL Call. No.: 100 T31P'Prairie' buffalograss response to selected pre-and post-emergenceherbicides--update.Marcum, K.B.; Engelke, M.C.College Station, Tex. : The Station; 1992 Sep.PR - Texas Agricultural Experiment Station (5002): p. 65-66; 1992 Sep.  In theseries analytic: Texas turfgrass research--1992.
Language:  English
Descriptors: Texas; Buchloe dactyloides; Herbicide resistance; Herbicides;Application rates; Crop damage
247                                                   NAL Call. No.: QH301.N32Producing herbicide tolerant populus using genetic transformation mediated byAgrobacterium tumefaciens C58: a summary of recent research.Riemenschnedier, D.E.; Haissig, B.E.New York, N.Y. : Plenum Press; 1991.NATO ASI series : Series A : Life sciences v. 210: p. 247-263; 1991.  In theseries analytic: Woody plant biotechnology / edited by M.R. Ahuja. Proceedingsof a Workshop at the Institute of Forest Genetics, USDA Forest Service,October 15-19, 1989, Placerville, California.  Literature review.  Includesreferences.
Language:  English
Descriptors: Populus alba; Populus grandidentata; Crosses; Cultivars; Genetictransformation; Glyphosate; Herbicide resistance; Agrobacterium tumefaciens;Literature reviews
248                                                    NAL Call. No.: 442.8 Z8Production and characterization of asymmetric somatic hybrids betweenArabidopsis thaliana and Brassica napus.Bauer-Weston, B.; Keller, W.; Webb, J.; Gleddie, S.Berlin, W. Ger. : Springer International; 1993 Apr.Theoretical and applied genetics v. 86 (2/3): p. 150-158; 1993 Apr.  Includesreferences.
Language:  English
Descriptors: Arabidopsis thaliana; Brassica napus; Somatic hybridization;Intergeneric hybridization; Protoplast fusion; X radiation; Gene transfer; Invitro selection; Herbicide resistance; Chlorsulfuron; Hybrids; Plantmorphology; Plant breeding
Abstract:  Cell suspension-derived protoplasts of a chlorsulfuron-resistant(GH50) strain of Arabidopsis thaliana cv Columbia were X-irradiated at 60 or90 krad, to facilitate the elimination of GH50 donor chromosomes in fusionproducts. Irradiated GH50 protoplasts were fused, with polyethylene glycol, toprotoplasts derived from stem epidermal strips of Brassica napus cv Westar.Chlorsulfuron-resistant colonies were selected in vitro and then transferredto shoot and root regeneration medium. Seventeen hybrid lines were regeneratedin vitro, and eight were successfully established in the greenhouse, wherethey flowered. These eight asymmetric hybrids were intermediate in vegetativemorphology between Arabidopsis and Brassica. The flowers from these hybridswere male-sterile with abnormal petal and pistil structures. Zymograms forphosphoglucomutase, esterase, and peroxidase showed the presence of allparental isozymes in each of the hybrids tested. Nuclear hybridity was alsoconfirmed for the ribosomal RNA genes using a wheat rDNA probe; however, thechloroplast genome in each of the hybrids was derived solely from the Brassicaparent. All selected somatic hybrids were capable of rooting at levels ofchlorsulfuron which were inhibitory to unfused Brassica plantlets. The degreeof herbicide resistance in the hybrid shoots is presently being evaluated.
249                                             NAL Call. No.: S494.5.B563B554Promoting crop protection by genetic engineering and conventional plantbreeding: problems and prospects.Woolhouse, H.W.Wallingford, Oxford, UK : CAB International; 1992.Biotechnology in agriculture v. 7: p. 249-256; 1992.  In the series analytic:Plant genetic manipulation for crop protection / edited by A.M.R. Gatehouse,V.A. Hilder and Boulter, D.
Language:  English
Descriptors: Crops; Genetic engineering; Genetic improvement; Plant breeding;Defense mechanisms; Insect control; Varietal resistance; Plant viruses;Herbicide resistance; Mixed cropping; Gene mapping; Breeding programs
250                                                  NAL Call. No.: 442.8 IN82Properties and uses of photoautotrophic plant cell cultures.Widholm, J.M.San Diego, Calif. : Academic Press; 1992.International review of cytology v. 132: p. 109-175; 1992.  Includesreferences.
Language:  English
Descriptors: Plants; Cell cultures; Growth; Photosynthesis; Celldifferentiation; Metabolism; Molecular biology; Genetic engineering; Herbicideresistance
251                                                   NAL Call. No.: QH301.N32PS II inhibitor binding, Q(B)-mediated electron flow and rapid degradation areseparable properties of the D1 reaction centre protein.Jansen, M.A.K.; Driesenaar, A.R.J.; Kless, H.; Malkin, S.; Mattoo, A.K.;Edelman, M.New York, N.Y. : Plenum Press; 1992.NATO ASI series : Series A : Life sciences v. 226: p. 303-311; 1992.  In theseries analytic: Regulation of chloroplast biogenesis / edited by J.H.Argyroudi-Akoyunoglou. Proceedings of a NATO Advanced Research Workshop, July28-August 3, 1991, Crete, Greece.  Includes references.
Language:  English
Descriptors: Spirodela oligorhiza; Mutants; Herbicide resistance; Light;Photosystem ii; Plant proteins; Biodegradation; Cytochromes; Electron transfer
252                                                    NAL Call. No.: 450 P693Purification and properties of a glyphosate-tolerant 5-enolpyruvylshikimate3-phosphate synthase from the cyanobacterium Anabaena variabilis.Powell, H.A.; Kerby N.W.; Rowell, P.; Mousdale, D.M.; Coggins, J.R.Berlin : Springer-Verlag; 1992.Planta v. 188 (4): p. 484-490; 1992.  Includes references.
Language:  English
Descriptors: Anabaena variabilis; Alkyl (aryl) transferases; Purification;Enzyme activity; Glyphosate; Herbicide resistance; Tolerance
Abstract:  5-Enolpyruvylshikimate 3-phosphate (EPSP) synthase(3-phosphoshikimate 1-carboxyvinyltransferase; EC 2.5.1.9) from theglyphosate-tolerant cyanobacterium Anabaena variabilis (ATCC 29413) waspurified to homogeneity. The enzyme had a similar relative molecular mass toother EPSP synthases and showed similar kinetic properties except for agreatly elevated K(i) for the herbicide glyphosate (approximately ten timeshigher than that of enzymes from other sources). With whole cells, themonoisopropylamine salt of glyphosate was more toxic than the free acid butthe effects of the free acid and monoisopropylamine salt on purified EPSPsynthase were identical.
253                                                      NAL Call. No.: S51.E2Purple nutsedge control with imazaquin in bermudagrass turf.Johnson, B.J.; Murphy, T.R.Athens, Ga. : The Stations; 1992 Feb.Research bulletin - University of Georgia, Agricultural Experiment Stations(408): 12 p.; 1992 Feb.  Includes references.
Language:  English
Descriptors: Georgia; Cynodon dactylon; Cyperus rotundus; Imazaquin; Lawns andturf; Weed control; Field tests; Herbicides; Herbicide resistance
254                                                    NAL Call. No.: 100 F663Pursuit: advantages and disadvantage in lettuce production.Dusky, J.A.; Al-Henaid, J.Belle Glade, Fla. : The Center; 1993 Feb.Belle Glade EREC research report EV - Florida University Agricultural Researchand Education Center (1993-2): p. 127-132; 1993 Feb.  Paper presented at theLettuce Research Workshop, February 4, 1993, Belle Glade, Florida.
Language:  English
Descriptors: Florida; Lactuca sativa; Imazethapyr; Weed control; Amaranthusspinosus; Amaranthus lividus; Herbicide resistance; Application rates;Bioassays; Soil analysis; Rotations; Application date; Crop yield
255                                                   NAL Call. No.: SB951.P49Pyridate is not a two-site inhibitor, and may be more prone to evolution ofresistance than other phenolic herbicides.Gressel, J.; Evron, Y.Orlando, Fla. : Academic Press; 1992 Oct.Pesticide biochemistry and physiology v. 44 (2): p. 140-146; 1992 Oct.Includes references.
Language:  English
Descriptors: Lactuca sativa; Pyridate; Mode of action; Pharmacodynamics;Photosynthesis; Herbicide resistance; Photosystem ii; Inhibitors; Binding site
Abstract:  Target site resistance has evolved to only those herbicidesaffecting a single system. Extensive resistance has evolved to photosystem IIinhibitors, especially atrazine, but not to the phenolic-type herbicides(e.g., dinoseb), which both affect photosystem II and purportedly uncouplemitochondrial phosphorylation and photophosphorylation. Pyridate, which hasbeen classified as a "phenolic"-type herbicide, is highly effective incontrolling triazine-resistant weeds. We demonstrate here that the activede-S-octyl derivative of pyridate does not have this second target site;photophosphorylation was only affected at 100 times greater concentration thanphotosystem II activity. From this point of view, pyridate may be more proneto evolution of resistance than phenolic-type herbicides with two sites ofaction.
256                                                    NAL Call. No.: 23 AU783Radiometry accurately measures chlorsulfuron injury to barley.Lemerle, D.; Fisher, J.A.; Hinkley, R.B.Melbourne : Commonwealth Scientific and Industrial Research Organization;1993.Australian journal of agricultural research v. 44 (1): p. 13-21; 1993.Includes references.
Language:  English
Descriptors: New South Wales; Hordeum vulgare; Cultivars; Crop damage;Herbicide resistance; Phytotoxicity; Chlorsulfuron
257                                                   NAL Call. No.: QK710.P63A rapid assay for chloroplast-encoded triazine resistance in higher plants.Cheung, W.Y.; Cote, J.C.; Benoit, D.L.; Landry, B.S.Athens, Ga. : International Society for Plant Molecular Biology, University ofGeorgia; 1993 Jun.Plant molecular biology reporter - ISPMB v. 11 (2): p. 142-155; 1993 Jun.Includes references.
Language:  English
Descriptors: Plant breeding; Genetic analysis; Chloroplasts; Genetic code;Triazine herbicides; Herbicide resistance; Laboratory methods; Rapid methods;Polymerase chain reaction; Dna amplification
258                                                   NAL Call. No.: SB610.W39Rapid diagnosis of ALS/AHAS-resistant weeds.Gerwick, B.C.; Mireles, L.C.; Eilers, R.J.Champaign, Ill. : The Weed Science Society of America; 1993 Apr.Weed technology : a journal of the Weed Science Society of America v. 7 (2):p. 519-524; 1993 Apr.  Includes references.
Language:  English
Descriptors: Herbicide resistant weeds; Biotypes; Detection; Assays; Herbicideresistance; Mode of action; Ligases; Enzyme inhibitors; Imazaquin; Abutilontheophrasti; Xanthium strumarium; Amaranthus retroflexus; Chenopodium album;Sorghum bicolor; Isomerases; Acetoin; Plant composition
259                                                    NAL Call. No.: 79.8 W41Rapid germination of sulfonylurea-resistant Kochia seoparia L. accessions isassociated with elevated seed levels of branched chain amino acids.Dyer, W.E.; Chee, P.W.; Fay, P.K.Champaign, Ill. : Weed Science Society of America; 1993 Jan.Weed science v. 41 (1): p. 18-22; 1993 Jan.  Includes references.
Language:  English
Descriptors: Kochia scoparia; Herbicide resistance; Susceptibility;Sulfonylurea herbicides; Seed germination; Soil temperature; Free amino acids;Isoleucine; Valine; Leucine; Enzymes; Enzyme activity
Abstract:  Field observations indicate that sulfonylurea-resistant kochia maygerminate at lower soil temperatures and/or germinate more rapidly thansusceptible kochia in the absence of herbicide. To investigate thispossibility, seeds from three resistant and two susceptible kochia accessionswere germinated at temperatures ranging from 4.6 to 13.2 degrees C on thermalgradient plates. At 4.6 and 13.2 degrees C, germination rates of all resistantaccessions were higher than susceptible accessions, while germination rates ofone resistant accession were higher than susceptible accessions at 7.2 and10.5 degrees C. Percent germination of all resistant accessions wassignificantly higher than susceptible accessions after 48 h at 4.6 degrees C.At higher temperatures, percent germination of some resistant accessions washigher after 12 or 24 h, but germination of all accessions was similar atlater times. HPLC analysis revealed that seeds from resistant accessionscontained about 2-fold higher free levels of branched chain amino acids thanseeds from susceptible accessions. The results indicate that mutationsconferring resistance to sulfonylurea herbicides in these kochia accessionsmay concomitantly reduce or abolish acetolactate synthase sensitivity tonormal feedback inhibition patterns, resulting in elevated levels of branchedchain amino acids available for cell division and growth during earlygermination.
260                                                   NAL Call. No.: SB951.P49Rapid metabolic inactivation is the basis for cross-resistance tochlorsulfuron in diclofop-methyl-resistant rigid ryegrass (Lolium rigidum)biotype SR4/84.Cotterman, J.C.; Saari, L.L.Orlando, Fla. : Academic Press; 1992 Jul.Pesticide biochemistry and physiology v. 43 (3): p. 182-192; 1992 Jul.Includes references.
Language:  English
Descriptors: Lolium rigidum; Biotypes; Herbicide resistant weeds; Herbicideresistance; Diclofop; Cross resistance; Chlorsulfuron; Metabolism; Metabolicdetoxification; Pharmacokinetics; Oxo-acid-lyases; Enzyme activity;Metabolites
Abstract:  Experiments were conducted to determine the mechanism ofcross-resistance to chlorsulfuron(2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino]carbonyl]benzenesulfonamide) in diclofop-methyl (methyl(+/-)-2-[4-(2,4-dichlorophenoxy)phenoxy]propanoic acid)-resistant rigidryegrass (Lolium rigidum Gaudin). In excised shoots and roots,[14C]chlorsulfuron was metabolized with a half-life of 1 and 3 hr,respectively, in the resistant biotype (SR4/84) versus 4 and 13 hrrespectively, in the susceptible biotype (SRS2). Based on coelution withstandards in high performance liquid chromatography (HPLC) and treatment withbeta-glucosidase followed by HPLC, the major chlorsulfuron metabolite inshoots and roots of both biotypes was identified as the herbicidally-inactiveglucose conjugate of hydroxy-chlorsulfuron. Acetolactate synthase (ALS, thetarget enzyme of chlorsulfuron) isolated from both biotypes was inhibited tothe same degree by chlorsulfuron. The glucose conjugate ofhydroxy-chlorsulfuron was inactive at the enzyme level, as it required greaterthan or equal to 36-fold higher concentrations compared to chlorsulfuron toinhibit the ALS from both biotypes. When [14C]chlorsulfuron was applied to theleaf surface, approximately 50% was absorbed within 48 hr by both biotypes. Ofthe radioactivity absorbed, less than 10% was translocated out of the treatedleaf in either biotype. Based on these results, chlorsulfuron resistance inSR4/84 is due to enhanced metabolic inactivation of the herbicide,specifically to the glucose conjugate, compared to the sensitive biotype.Resistance is not due to reduced sensitivity of ALS or increased uptake ortranslocation in SR4/84.
261                                                    NAL Call. No.: QH442.B5Rapid production of transgenic wheat plants by direct bombardment of culturedimmature embryos.Vasil, V.; Srivastava, V.; Castillo, A.M.; Fromm, M.E.; Vasil, I.K.New York, N.Y. : Nature Publishing,; 1993 Dec.Bio/technology v. 11 (13): p. 1553-1558; 1993 Dec.  Includes references.
Language:  English
Descriptors: Triticum aestivum; Genetic transformation; Plant embryos;Transgenic plants; Reporter genes; Beta-glucuronidase; Acyltransferases;Herbicide resistance; Plasmid vectors; Inheritance; Segregation; Glufosinate;Callus; Embryogenesis; In vitro selection
262                                                   NAL Call. No.: SB610.W39Rationale for developing herbicide-resistant crops.Burnside, O.C.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 621-625; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Herbicide resistance; Genotypes;Biotechnology; Weed control; Risk
263                                                   NAL Call. No.: 64.8 C883Recurrent selection for glyphosate tolerance in birdsfoot trefoil.Boerboom, C.M.; Ehlke, N.J.; Wyse, D.L.; Somers, D.A.Madison, Wis. : Crop Science Society of America; 1991 Sep.Crop science v. 31 (5): p. 1124-1129; 1991 Sep.  Includes references.
Language:  English
Descriptors: Lotus corniculatus; Weed control; Cirsium arvense; Chemicalcontrol; Glyphosate; Herbicide resistance; Selection criteria; Recurrentselection; Enzyme activity; Ligases
Abstract:  Glyphosate [N-(phosphonomethyl)glycine] tolerant birdsfoot trefoil(Lotus corniculatus L.) would allow selective herbicide control of Canadathistle [Cirsium arvense (L.) Scop.] and other dicot weeds in seed productionfields. The objectives of this research were to determine if recurrentselection can increase the level of glyphosate tolerance in birdsfoot trefoiland if increased glyphosate tolerance is associated with increased5-enolpyruvylshikimate 3-phosphate (EPSP) synthase activity. Two cycles ofselection for glyphosate tolerance were made in three birdsfoot trefoilgermplasms, Leo', Norcen', and MU-81' by selecting seedlings followingtreatment with 0.56 kg ae/ha (kg acid equivalents per hectare) of glyphosate.To evaluate tolerance, seedings with eight leaves of the selected and parentalpopulations were either untreated or treated with 0.56 kg ae/ha of glyphosateplus surfactant in a greenhouse. Shoot fresh weights were measured 14 daysafter treatment (DAT) and regrowth was measured 35 DAT. Treated shoot weightsof the three C2 populations were from 44 to 85% greater than their C0populations, indicating increased glyphosate tolerance. The evaluation ofregrowth weights also showed 44 to 127% increases in the C0 populations.Tolerant plants from C2 populations had greater EPSP synthase-specificactivity (the primary site of action of glyphosate) than susceptible C0plants. This suggested that tolerance was at least partially conferred byincreased EPSP synthase activity. Genetic variance should allow continuedprogress from selection for increased glyphosate tolerance in birdsfoottrefoil.
264                                                   NAL Call. No.: QK725.P54Regeneration of herbicide resistant transgenic rice plants followingmicroprojectile-mediated transformation of suspension culture cells.Cao, J.; Duan, X.L.; McElroy, D.; Wu, R.Berlin, W. Ger. : Springer International; 1992.Plant cell reports v. 11 (11): p. 586-591; 1992.  Includes references.
Language:  English
Descriptors: Oryza sativa; Cell suspensions; Genetic transformation; Dna; Genetransfer; Plasmids; Herbicide resistance; Glufosinate; Gene expression;Selection; Gene mapping; Nucleotide sequences
Abstract:  Suspension cells of Oryza sativa L. (rice) were transformed, bymicroprojectile bombardment, with plasmids carrying the coding region of theStreptomyces hygroscopicus phosphinothricin acetyl transferase (PAT) gene(bar) under the control of either the 5' region of the rice actin 1 gene(Act1) or the cauliflower mosaic virus (CaMV) 35S promoter. Subsequentlyregenerated plants display detectable PAT activity and are resistant to BASTA,a phosphinothricin (PPT)-based herbicide. DNA gel blot analyses showed thatPPT resistant rice plants contain a bar-hybridizing restriction fragment ofthe expected size. This report shows that expression of the bar gene intransgenic rice plants confers resistance to PPT-based herbicide bysuppressing an increase of ammonia in plants after spraying with theherbicide.
265                                            NAL Call. No.: QK882.P5577 1993Regulation of electron transport at the acceptor side of photosystem II byherbicides, bicarbonate and formate.Rensen, J.S. vanDordrecht : Kluwer Academic Publishers; 1993.Photosynthesis : photoreactions to plant productivity / edited by Yash PalAbrol, Prasanna Mohanty, Govindjee. p. 157-180; 1993.  Literature review.Includes references.
Language:  English
Descriptors: Photosynthesis; Photosystem ii; Electron transfer; Quinones;Herbicides; Herbicidal properties; Formic acid; Organic anions; Carbon;Anions; Herbicide resistance; Binding site; Literature reviews; Plant proteins
Abstract:  The photosystem II reaction center can be considered as awater-plastoquinone oxido-reductase. Using four photons it transfers fourelectrons from two molecules of water to plastoquinone producing molecularoxygen and two molecules of doubly reduced plastoquinone. Our understanding ofthe structure and function of this complex has greatly increased during therecent years. The basis of the reaction center of photosystem II is formed bythe D1 and D2 proteins, both having a molecular mass of about 32 kDa. The D1protein contains not only the binding site for the physiological electroncarrier QB, but also the binding sites for several classes of herbicides andfor bicarbonate and formate. Both the diuron-type and the phenol-typeherbicides act by replacing the physiological electron carrier QB from itsbinding site at the D1 protein. Because the herbicides cannot be reduced, theelectron flow is interrupted between the primary electron acceptor ofphotosystem II QA, and the plastoquinone pool. There appears a relationbetween the residence time of a herbicide at the D1 protein and its activityas an inhibitor of electron flow. Incubation of isolated chloroplasts withformate, while flushing them with nitrogen gas, results in full inhibition ofelectron flow activity, which can be restored by addition of bicarbonate. Thisantagonistic action of formate and bicarbonate is located at the D1 proteinand affects electron flow between QA and the plastoquinone pool. The advancesin this field should encourage future work on the mechanism of the action offormate and bicarbonate at the molecular level as well as on their action invivo. The study of triazine-resistance in weeds and herbicide-resistance inalgae and photosynthetic bacteria has resulted in the recognition of a commonbinding niche for QB, herbicides, formate and bicarbonate at the D1 proteinincluding the hydrophobic transmembrane helices IV and V and the parallelhelix connecting these on the matrix side of the D1 protein.
266                                                    NAL Call. No.: 450 P692Regulation of photosynthesis in trizaine-resistant and -susceptible Brassicanapus.Dekker, J.H.; Sharkey, T.D.Rockville, Md. : American Society of Plant Physiologists; 1992 Mar.Plant physiology v. 98 (3): p. 1069-1073; 1992 Mar.  Includes references.
Language:  English
Descriptors: Brassica napus; Photosynthesis; Regulation; Triazines; Netassimilation rate; Chlorophyll; Fluorescence; Temperature; Biotypes; Herbicideresistance
Abstract:  The response of photosynthetic carbon assimilation and chlorophyllfluorescence quenching to changes in intercellular CO2 partial pressure(C(i)), O2 partial pressure, and leaf temperature (15-35 degrees C) intriazine-resistant and -susceptible biotypes of Brassica napus were examinedto determine the effects of the changes in the resistant biotype on theoverall process of photosynthesis in intact leaves. Three categories ofphotosynthetic regulation were observed. The first category of photosyntheticresponse, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco)-limitedphotosynthesis, was observed at 15, 25, and 35 degrees C leaf temperatureswith low C(i). When the carbon assimilation rate was Rubisco-limited, therewas little difference between the resistant and susceptible biotypes, andRubisco activity parameters were similar between the two biotypes. A secondcategory, called feedback-limited photosynthesis, was evident at 15 and 25degrees C above 300 microbars C(i). The third category, photosyntheticelectron transport-limited photosynthesis, was evident at 25 and 35 degrees Cat moderate to high CO2. At low temperature, when the response curves ofcarbon assimilation to C(i) indicated little or no electron transportlimitation, the carbon assimilation rate was similar in the resistant andsusceptible biotypes. With increasing temperature, more electrontransport-limited carbon assimilation was observed, and a greater differencebetween resistant and susceptible biotypes was observed. These observationsreveal the increasing importance of photosynthetic electron transport incontrolling the overall rate of photosynthesis in the resistant biotype astemperature increases. Photochemical quenching of chlorophyll fluorescence(q(p)) in the resistant biotype never exceeded 60%, and triazine resistanceeffects were more evident when the susceptible biotype had greater than 60%q(p), but not when it had less than 60% q(p).
267                                                    NAL Call. No.: 79.8 W41Relationship of leaf surface characteristics to acifluorfen tolerance intomato (Lycopersicon esculentum) and related species.Ricotta, J.A.; Masiunas, J.B.Champaign, Ill. : Weed Science Society of America; 1992 Jul.Weed science v. 40 (3): p. 402-407; 1992 Jul.  Includes references.
Language:  English
Descriptors: Lycopersicon esculentum; Weed control; Solanum; Genotypes;Herbicide resistance; Screening; Acifluorfen; Leaves; Cuticle; Waxes;Trichomes; Density; Stomata
Abstract:  Fourteen tomato genotypes, eastern black nightshade, and 35Lycopersicon accessions were screened for tolerance to acifluorfen. Tolerantand susceptible genotypes occurred in most species. Fifteen genotypes werechosen for further study depending on their fresh weight after acifluorfentreatment. Over all 15 genotypes, there was no correlation between trichomedensity and acifluorfen tolerance; however, in L. esculentum, cultivars withthe most trichomes were the most tolerant. There was an inverse relationshipbetween stomata density and tolerance. Amount and composition of epicuticularwax and cuticle thickness did not correlate to acifluorfen tolerance.
268                                                    NAL Call. No.: 450 P693Relationships among the herbicide and functional sites of acetohydroxy acidsynthase from Chlorella emersonii.Landstein, D.; Arad, S.M.; Barak, Z.; Chipman, D.M.Berlin ; New York : Springer-Verlag, 1925-; 1993.Planta v. 191 (1): p. 1-6; 1993.  Includes references.
Language:  English
Descriptors: Chlorella; Oxo-acid-lyases; Enzyme activity; Inhibition;Sulfometuron; Mutants; Herbicide resistance; Anilide herbicides; Imidazolinoneherbicides; Binding site; Amino acid sequences
Abstract:  The properties of acetohydroxy acid synthase (AHAS, EC 4.1.3.18)from wild-type Chlorella emersonii (var. Emersonii, CCAP-211/11n) and twospontaneous sulfometuron methyl (SMM)-resistant mutants were examined. TheAHAS from both mutants was resistant to SMM and cross-resistant to imazapyr(IM) and the triazolopyrimidine sulfonanilide herbicide XRD-498 (TP). Themore-SMM-resistant mutant had AHAS with altered catalytic parameters (Km,specificity), but unchanged sensitivity to the feedback inhibitors valine andleucine. The second mutant enzyme was less sensitive to the feedbackinhibitors, but had otherwise unchanged kinetic parameters.Inhibition-competition experiments indicated that the three herbicides (SMM,IM, TP) bind in a mutually exclusive manner, but that valine can bindsimultaneously with SMM or TP. The three herbicide classes apparently bind toclosely overlapping sites. We suggest that the results with C. emersonii andother organisms can all be explained if there are separate binding sites forherbicides, feedback inhibitors and substrates.
269                                                   NAL Call. No.: QH301.A76Residual herbicides for newly planted farm woodlands: efficacy and treetolerance.Britt, C.P.Wellesbourne, Warwick : The Association of Applied Biologists; 1992.Aspects of applied biology (29): p. 211-218; 1992.  In the series analytic:Vegetation management in forestry, amenity and conservation areas. Paperpresented at the conference of the Association, April 7-9, 1992, University ofYork, England.  Includes references.
Language:  English
Descriptors: England; Acer pseudoplatanus; Fraxinus excelsior; Prunus avium;Survival; Weed control; Weeds; Farm woodlands; Herbicide mixtures; Herbicideresidues; Herbicide resistance
270                                                   NAL Call. No.: SB957.R47Resistance of giant foxtail (Setaria faberi Herrm.) and large crabgrass[Digitaria sanguinalis (L.) Scop.] biotypes to acetyl-coenzyme A carboxylaseinhibitors.Wiederholt, R.J.; Stoltenberg, D.E.East Lansing, Mich. : Pesticide Research Center, Michigan State University,;1993.Resistant pest management v. 5 (2): p. 17-18; 1993.
Language:  English
Descriptors: Wisconsin; Cabt; Setaria faberi; Digitaria sanguinalis; Biotypes;Herbicide resistant weeds; Herbicide resistance; Enzyme inhibitors; Acetylcoenzyme a
271                                                   NAL Call. No.: SB610.W39Resistance of Palmer amaranth (Amaranthus palmeri) to the dinitroanilineherbicides.Gossett, B.J.; Murdock, E.C.; Toler, J.E.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 587-591; 1992 Jul.  Includes references.
Language:  English
Descriptors: South Carolina; Amaranthus palmeri; Biotypes; Trifluralin;Herbicide resistance; Susceptibility; Cross resistance; Herbicides;Application rates; Weed control; Chemical control
272                                                   NAL Call. No.: SB610.W39Resistance of selected ornamental grasses to graminicides.Catanzaro, C.J.; Skroch, W.A.; Burton, J.D.Champaign, Ill. : The Weed Science Society of America; 1993 Apr.Weed technology : a journal of the Weed Science Society of America v. 7 (2):p. 326-330; 1993 Apr.  Includes references.
Language:  English
Descriptors: Ornamental plants; Panicum virgatum; Festuca ovina; Pennisetumalopecuroides; Festuca; Erianthus; Herbicide resistance; Fenoxaprop;Fluazifop-p; Quizalofop; Sethoxydim; Phytotoxicity
273                                                    NAL Call. No.: 450 P692Resistance to acetolactate synthase-inhibiting herbicides in annual ryegrass(Lolium rigidum) involves at least two mechanisms.Christopher, J.T.; Powles, S.B.; Holtum, J.A.M.Rockville, MD : American Society of Plant Physiologists, 1926-; 1992 Dec.Plant physiology v. 100 (4): p. 1909-1913; 1992 Dec.  Includes references.
Language:  English
Descriptors: Lolium rigidum; Herbicide resistant weeds; Chlorsulfuron;Sulfonylurea herbicides; Imidazolinone herbicides; Oxo-acid-lyases; Enzymeactivity; Cross resistance; Diclofop; Herbicidal properties; Metabolism;Biotypes
Abstract:  WLR1, a biotype of Lolium rigidum Gaud. that had been treated withthe sulfonylurea herbicide chlorsulfuron in 7 consecutive years, was found tobe resistant to both the wheat-selective and the nonselective sulfonylurea andimidazolinone herbicides. Biotype SLR31, which became cross-resistant tochlorsulfuron following treatment with the aryloxyphenoxypropionate herbicidediciofop-methyl, was resistant to the wheat-selective, but not thenonselective, sulfonylurea and imidazolinone herbicides. The concentrations ofherbicide required to reduce in vitro acetolactate synthase (ALs) activity 50%with respect to control assays minus herbicide for biotype WLR1 was greaterthan those for susceptible biotype VLR1 by a factor of >30, >30, 7, 4, and 2for the herbicides chlorsulfuron, sulfometuron-methyl, imazapyr, imazathapyr,and imazamethabenz, respectively. ALS activity from biotype SLR31 responded ina similar manner to that of the susceptible biotype VLR1. The resistantbiotypes metabolized chlorsulfuron more rapidly than the susceptible biotype.Metabolism of 50% of [phenyl-U-14C] chlorsulfuron in the culms of two-leafseedlings required 3.7 h in biotype SLR31, 5.1 h in biotype WLR1, and 7.1 h inbiotype VLR1. In all biotypes the metabolism of chlorsulfuron in the culms wasmore rapid than that in the leaf lamina. Resistance to ALS inhibitors in L.rigidum may involve at least two mechanisms, increased metabolism of theherbicide and/or a herbicide-insensitive ALS.
274                                                    NAL Call. No.: 79.8 W41Resistance to aryloxyphenoxypropionate herbicides in two wild oat species(Avena fatua and Avena sterilis ssp. ludoviciana).Mansooji, A.M.; Holtum, J.A.; Boutsalis, P.; Matthews, J.M.; Powles, S.B.Champaign, Ill. : Weed Science Society of America; 1992.Weed science v. 40 (4): p. 599-605; 1992.  Includes references.
Language:  English
Descriptors: Australia; Avena fatua; Avena sterilis subsp. ludoviciana;Herbicide resistant weeds; Herbicide resistance; Cross resistance; Diclofop;Biotypes; Fluazifop; Haloxyfop; Fenoxaprop; Quizalofop; Propaquizafop;Sethoxydim; Cycloxydim; Tralkoxydim
Abstract:  Resistance to the methyl ester of diclofop, anaryloxyphenoxypropionate graminicide, was shown for a wild oat (Avena fatua)population from Western Australia, and marked resistance to a range ofaryloxyphenoxypropionate and cyclohexanedione graminicides was detected in awinter wild oat (Avena sterilis ssp. ludoviciana) population from SouthAustralia. The A. sterilis biotype exhibited high levels of resistance to thearyloxyphenoxypropionate herbicides diclofop, fluazifop, haloxyfop,fenoxaprop, quizalofop, propaquizafop, and quinfurop and low levels ofresistance to the cyclohexanedione herbicides sethoxydim, tralkoxydim, andcycloxydim. Ratios of LD50 values for responses of resistant and susceptible-  sterilis to the aryloxyphenoxypropionate herbicides were between 20 forpropaquizafop and > 1,000 for fluazifop, and were between 2.5 and 3 for thecyclohexanedione herbicides. The LD50 value for diclofop for the A. fatuabiotype was 442 g ai ha-1 which was 2.7-fold that of a susceptible control.Thirty-three percent of the plants survived at the registered rate ofapplication.  275                                                    NAL Call. No.: 450 P692Resistance to the herbicide paraquat and increased tolerance tophotoinhibition are not correlated in several weed species.Preston, C.; Holtum, J.A.M.; Powles, S.B.Rockville, Md. : American Society of Plant Physiologists; 1991 May.Plant physiology v. 96 (1): p. 314-318; 1991 May.  Includes references.
Language:  English
Descriptors: Australia; Hordeum glaucum; Conyza bonariensis; Hordeum murinumsubsp. leporinum; Arctotheca calendula; Herbicide resistant weeds; Paraquat;Biotypes; Photoinhibition; Resistance
Abstract:  Photoinhibition was examined in paraquat-resistant andparaquat-susceptible biotypes of Hordeum glaucum Steud., Hordeum leporinumLink., Arctotheca calendula (L.) Levyns., and Conyza bonariensis (L.) Cronq.Plants were photoinhibited at low temperature, and the extent ofphotoinhibition determined by O2 evolution and 77 K fluorescence. Nodifference in the degree of photoinhibition was detected betweenparaquat-resistant and paraquat-susceptible biotypes for any of the speciesexamined. C. bonariensis plants were also photoinhibited by treatment withoutCO2 at either 21% (volume/volume) O2 or 4% (volume/volume) O2, and again nodifference was observed between the paraquat-resistant andparaquat-susceptible biotypes in reduction of the ratio of variablefluorescence to maximal fluorescence. This is in contrast to a recent report(MAK Jansen, Y Shaaltiel, D Kazzes, 0 Canaani, S Malkin, J Gressel, [1989]Plant Physiol 91: 1174-1178 in which it was claimed that a paraquat-resistantbiotype of C. bonariensis was more tolerant of photoinhibition than aparaquat-susceptible biotype. We conclude that paraquat-resistant biotypes ofthese plant species are not more tolerant of photoinhibition when comparedwith the paraquat-susceptible biotypes.
276                                                   NAL Call. No.: 64.8 C883Resistance to the sulfonylurea herbicides chlorsulfuron, amidosulfuron, andDPX-R9674 in transgenic flue-cured tobacco.Brandle, J.E.; Labbe, H.; Zilkey, B.F.; Miki, B.L.Madison, Wis. : Crop Science Society of America; 1992 Jul.Crop science v. 32 (4): p. 1049-1053; 1992 Jul.  Includes references.
Language:  English
Descriptors: Canada; Nicotiana tabacum; Herbicide resistance; Sulfonylureaherbicides; Transgenics; Agrobacterium; Genetic transformation; Genotypes;Application rates; Seedlings; Treatment; Selection criteria; Gene expression;Genetic analysis
Abstract:  Only one herbicide is currently available for preemergencebroadleaf weed control in flue-cured tobacco (Nicotiana tabacum L.) grown inCanada. The high cost of registration, coupled with the small crop size, hasresulted in few new products becoming available. Herbicide resistanceintroduced into tobacco by Agrobacterium-mediated transformation formation mayallow the use of products with existing or impending registrations. We usedtwo new, low-residual sulfonylurea herbicides: amidosulfuron (3-(4,6-dimethoxyprymidin-2-yl)-l-(N-methyl-N-methylsulfonyl-aminosulfonylurea) andDPX-R9674, which is a mixture of thifensulfuron(methyl-3-[[[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino) carbonyl] amino]sulfonyl]-2-thiophenecarboxylate) and tribenuron (methyl2[[[[N-4-methoxy-6-methyl-1,3,5-triazin-2-yl) methylaminol carbonyl] amino]sulfonyl] benzoate). These two and chlorsulfuron(2-chloro-N-[(4-methoxy-6-methyl-1,3,5-triazin-2-yl) aminocarbonyl]benzenesulfonamide) were applied to two transgenic tobacco genotypes harboringthe csr1-1 gene for chlorsulfuron resistance and compared with anuntransformed control. Our purpose was to determine if transgenic seedlingswere resistant to DPX-R9674 and amidosulfuron. The experiment was a factorialin a completely randomized design with 25 replications. The three herbicideswere applied to the transgenic and control seedlings at three rates. Thetransgenic seedlings had significantly higher leaf area, top dry weight, androot dry weight than the untransformed control when sprayed with any of thethree herbicides. Seedlings were highly resistant to amidosulfuron andchlorsulfuron. Resistance to DPX-R9674 in the transgenic seedlings wasminimal, which was unexpected, considering that an analysis of AHAS activityrevealed high levels of cross-resistance to chlorsulfuron, DPX-R9674, andamidosulfuron. It is possible that DPX-R9674 is metabolized into products thatare herbicidally active at different AHAS binding sites. One of transgeniclines was more resistant to herbicide application than the other indicatingthat selection for maximum gene expression among transgenic lines isnecessary part of transgenic cultivar development.  It  was conclued thatDPX-R9674 would not be suitable for use with transgenic crops harboring thecsr1-1 gene for chlorsulfuron resistance.  The other low-residualsulfonylurea, amidosulfuron, was more promising.
277                                                    NAL Call. No.: 79.8 W41Response of a chlorsulfuron-resistant biotype of Kochia scoparia tosulfonylurea and alternative herbicides.Friesen, L.F.; Morrison, I.N.; Rashid, A.; Devine, M.D.Champaign, Ill. : Weed Science Society of America; 1993 Jan.Weed science v. 41 (1): p. 100-106; 1993 Jan.  Includes references.
Language:  English
Descriptors: Manitoba; Cabt; Kochia scoparia; Biotypes; Chlorsulfuron;Herbicide resistance; Herbicide resistant weeds; Cross resistance;Susceptibility; Herbicides; Weed control
Abstract:  Kochia growing on an industrial site where chlorsulfuron wasapplied repeatedly over several seasons was confirmed to be resistant tochlorsulfuron and several other acetolactate synthase (ALS) -inhibitingherbicides. In growth room experiments, resistant (R) plants were 2 to > 180times more resistant to five sulfonylurea herbicides and one imidazolinoneherbicide (imazethapyr) than susceptible (S) plants, as measured by the ratioof dosages required to inhibit shoot dry matter accumulation by 50% (GR50R/S). Similarly, in vitro assays of ALS activity indicated that from 3 to 30times more herbicide was required to inhibit the enzyme from R plants thanfrom S plants. Results of ALS enzyme assays indicated that R kochia wasapproximately equally resistant to metsulfuron, triasulfuron, andthifensulfuron, and 2.5 times more resistant to tribenuron thanthifensulfuron. However, the response of R kochia growing in a spring wheatcrop in the field was not consistent with results of the ALS enzyme assays. Infield experiments, thifensulfuron at 32 g ai ha-1 had little effect on Rkochia. In contrast, metsulfuron, triasulfuron, and tribenuron at 8 g ha-1 didnot reduce R kochia seedling densities, but caused severe stunting such that 2mo after treatment the shoot biomass of plants in untreated plots was fourtimes greater than in sprayed plots. Herbicides with alternative modes ofaction including fluroxypyr, bromoxynil/MCPA ester, dichlorprop/2,4-D ester,and 2,4-D ester provided good control of R kochia in the field. Quinclorac didnot reduce kochia densities, but surviving plants were stunted. To delay oravoid development of ALS inhibitor-resistant kochia populations, thesealternative herbicides applied alone or in tank mixtures could be incorporatedinto a herbicide rotation.
278                                                   NAL Call. No.: SB610.W39Response of common bean (Phaseolus vulgaris) cultivars to metobromuron.Park, S.J.; Hamill, A.S.Champaign, Ill. : The Weed Science Society of America; 1993 Jan.Weed technology : a journal of the Weed Science Society of America v. 7 (1):p. 70-75; 1993 Jan.  Includes references.
Language:  English
Descriptors: Ontario; Cabt; Phaseolus vulgaris; Cultivars; Varietalsusceptibility; Metobromuron; Herbicide resistance; Screening; Phytotoxicity;Crop damage; Seedling stage; Application rates
279                                                    NAL Call. No.: 79.8 W41Response of corn (Zea mays L.) inbreds and hybrids to sulfonylurea herbicides.Green, J.M.; Ulrich, J.F.Champaign, Ill. : Weed Science Society of America; 1993 Jul.Weed science v. 41 (3): p. 508-516; 1993 Jul.  Includes references.
Language:  English
Descriptors: Zea mays; Inbred lines; Hybrids; Herbicide resistance;Sulfonylurea herbicides; Chlorimuron; Metsulfuron; Tribenuron; Sulfometuron;Phytotoxicity; Varietal susceptibility; Recessive genes; Plant breeding
Abstract:  Extensive field and greenhouse studies were done to characterizevarietal response of three recently commercialized sulfonylurea cornherbicides: nicosulfuron, primisulfuron, and thifensulfuron. Most of the 94varieties tested were highly tolerant to these herbicides. The 37 inbredsrepresented all major inbred families now used in hybrid seed production aswell as several sensitive experimentals. Twenty-one defined hybrids from theseinbreds as well as 36 commercially coded hybrids were also tested. Sensitiveinbreds produced tolerant hybrids when crossed with tolerant inbreds.Sensitive hybrids occurred when both parents were sensitive. Genetic analysisof sensitive by tolerant crosses showed that sensitivity is controlled by asingle recessive gene. Nicosulfuron had the widest corn safety margin andfewest sensitive varieties. Dose response analysis showed varieties can varymore than 40 000-fold in sensitivity. Only corn varieties with theAHAS-modified XA-17 gene showed any change in enzyme sensitivity. This geneovercame sensitivity to sulfonylureas, even when the organophosphateinsecticide terbufos was present. Thus, breeders have three options toeliminate sulfonylurea sensitivity: backcross sensitive inbreds with tolerant,always use at least one tolerant hybrid parent, or use the XA-17 gene.
280                                                   NAL Call. No.: SB610.W39Response of quackgrass (Elytrigia repens) biotypes to primisulfuron.Gillespie, G.R.; Vitolo, D.B.Champaign, Ill. : The Weed Science Society of America; 1993 Apr.Weed technology : a journal of the Weed Science Society of America v. 7 (2):p. 411-416; 1993 Apr.  Includes references.
Language:  English
Descriptors: New York; Cabt; Ohio; Cabt; Pennsylvania; Cabt; Minnesota; Cabt;Massachusetts; Cabt; North Dakota; Cabt; Elymus repens; Biotypes; Weedbiology; Herbicide resistant weeds; Provenance; Herbicide resistance;Sulfonylurea herbicides; Weed control; Chemical control; Application rates;Additives
281                                                    NAL Call. No.: 500 T25AResponse of several cucumber cultivar seedlings to ethalfluralin andpendimethalin in vitro.Kennedy, J.M.; Caponetti, J.D.; Jeffery, L.S.Hixson, Tenn. : The Academy; 1991 Jul.Journal of the Tennessee Academy of Science v. 66 (3): p. 111-114; 1991 Jul.Includes references.
Language:  English
Descriptors: Cucumis sativus; Cultivars; Seedlings; Injuries; Herbicideresistance; Ethalfluralin; Pendimethalin
282                                         NAL Call. No.: ArUSB608.R5B42 1991Rice response to rotational crop herbicides.Beaty, Jackie Dwayne1991; 1991.x, 47 leaves ; 28 cm.  May 1991.  Includes bibliographical references (leaf16).
Language:  English
Descriptors: Rice; Herbicide resistance; Crop rotation
283                                                   NAL Call. No.: SB951.P49Role of glutathione and glutathione S-transferase in the selectivity ofacetochlor in maize and wheat.Jablonkai, I.; Hatzios, K.K.Orlando, Fla. : Academic Press; 1991 Nov.Pesticide biochemistry and physiology v. 41 (3): p. 221-231; 1991 Nov.Includes references.
Language:  English
Descriptors: Zea mays; Triticum aestivum; Roots; Shoots; Plant composition;Chemical composition; Glutathione; Enzyme activity; Glutathione transferase;Metabolic detoxification; Acetochlor; Selectivity; Hybrid varieties;Cultivars; Varietal susceptibility; Genotypes; Genetic variation; Seedlings;Phytotoxicity; Herbicide resistance; Pharmacokinetics
Abstract:  The role of shoot and root glutathione (GSH) content andglutathione S-transferase (GST) activity in the response of the 'A632 X A635'and 'Anjou SC256' hybrids of maize (Zea mays L.) and of 'Jubilejnaja 50' wheat(Triticum aestivum L.) to the chloroacetanilide herbicide acetochlor wasevaluated. The concentrations of root-applied acetochlor causing a 50%inhibition of plant shoot height were 20 micromoles for the tolerant 'A632 XA635' maize, 1 micromole for the sensitive 'Anjou SC256' maize, and 0.1micromoles for the very sensitive 'Jubilejnaja 50' wheat. The nonprotein thiol(mainly GSH) level in the roots of the tolerant 'A632 X A635' maize hybrid was2-fold greater than that found in the roots of the sensitive maize hybrid andof wheat. Pretreatment with 10 micromoles of acetochlor induced the rootnonprotein thiol levels of all three genotypes. The highest induction of rootthiol content compared to controls was observed at 48 hr after acetochlortreatment and was 2.23-fold in the tolerant maize and 1.72-fold for thesensitive wheat. GST activities of etiolated maize and wheat seedlings wereevaluated using both CDNB (1-chloro-2,4-dinitrobenzene) and [14C]-acetochloras substrates. GST(CDNB) activity was greater in the roots than in the shootsof both maize hybrids. The shoot activity of both maize genotypes was similar,but the tolerant 'A632 X A635' maize had slightly higher root GST(CDNB)activity. In the sensitive wheat, similar shoot and root activities wereobserved. GST(CDNB) activity in roots of the maize hybrids and of wheat wasenhanced by 70-100% at 48 hr after pretreatment with 10 micromoles ofacetochlor. Shoot GST(CDNB) activity of maize or wheat was not inducedsignificantly by acetochlor pretreatment. Root and shoot GST(acetochlor)activities of the maize hybrids and wheat were much lower than GST(CDNB)activities. Root GST(acetochlor) activities of the two maize hybrids weregreater and more inducible by acetochlor pretreatment than those of thesensitive wheat.  These results demonstrate the important role of endogenouslevels of GSH and of GST activity in chloroacetanilide herbicide detoxicationand selectivity.
284                                                    NAL Call. No.: 450 P692S1 destabilization and higher sensitivity to light in metribuzin-resistantmutants.Perewoska, I.; Etienne, A.L.; Miranda, T.; Kirilovsky, D.Rockville, MD : American Society of Plant Physiologists, 1926-; 1994 Jan.Plant physiology v. 104 (1): p. 235-245; 1994 Jan.  Includes references.
Language:  English
Descriptors: Cyanobacteria; Photosystem ii; Redox potential; Electrontransfer; Quinones; Binding proteins; Herbicide resistance; Metribuzin;Mutants; Mutations; Photoinhibition; Light; Stress; Amino acid sequences;Structural genes
Abstract:  Mutations in the secondary quinone electron acceptor pocket of theD1 protein conferring a modification on the donor side of photosystem II(PSII) have been characterized by gene cloning and sequencing in twometribuzin-resistant mutants of Synechocystis PCC 6714. The mutations inducedifferent herbicide resistances: in M30, a point mutation at the codon 248,isoleucine to threonine, results in resistance only to metribuzin; in a singlemutation, Ala251Val, confers metribuzin, atrazine, and ioxynil resistance. Aswith other herbicide-resistant mutants, and present modifications in theelectron transfer between the primary quinone electron acceptor and (QA) andQB. In addition, they have a modified oscillatory pattern of oxygen emission:after dark adaptation, the maximum oscillation is shifted by one flash. Bothmutants have a higher concentration of the redox state in the dark-adaptedstate than the wild type. The mutations render the oxygen-evolving system moreaccessible to cell reductants. The mutation Ala251Val also confers to PSII anincreased sensitivity to high light. We have already demonstrated thatunderlight stress a double mutant, AzV (Ala251Val, Phe211Ser), lost theability to recover the PSII activity sooner than the wild type. Here, weconfirm that the modification of the alanine-251 is responsible for thisspecific sensitivity to high light. We conclude that specific mutations of theQB pocket modify the behavior of the cells under light stress and have aneffect on the structure of the D1 protein in the other side of the membrane.
285                                                   NAL Call. No.: SB610.W39Seed biology of sulfonylurea-resistant and -susceptible biotypes of pricklylettuce (Lactuca serriola).Alcocer-Ruthling, M.; Thill, D.C.; Shafii, B.Champaign, Ill. : The Weed Science Society of America; 1992 Oct.Weed technology : a journal of the Weed Science Society of America v. 6 (4):p. 858-864; 1992 Oct.  Includes references.
Language:  English
Descriptors: Idaho; Cabt; Lactuca serriola; Biotypes; Sulfonylurea herbicides;Herbicide resistance; Susceptibility; Competitive ability; Seed longevity;Seed germination; Fecundity
286                                                   NAL Call. No.: QK725.P54Selection of atrazine tolerant soybean calli and expression of that tolerancein regenerated plants.Wrather, J.A.; Freytag, A.H.Berlin, W. Ger. : Springer International; 1991.Plant cell reports v. 10 (1): p. 44-47; 1991.  Includes references.
Language:  English
Descriptors: Glycine max; Plant breeding; In vitro selection; Atrazine;Herbicide resistance; Callus; Regenerative ability; Phytotoxicity; Selection
Abstract:  Lines of soybean [Glycine max (L.)] tolerant of atrazine weredeveloped by an in vitro and in vivo atrazine challenge. Cotyledonary nodeplus epicotyl explants from mature germinated seed of soybean introduction PI438489B were cultured on RV-5 medium containing 48 mg active ingredient(a.i.)/l atrazine for one month. Most of the explants (66%) on mediumcontaining atrazine, and 10% on medium without atrazine died. Explantssurviving exposure to atrazine callused and organogenically regenerated shootsdeveloped. Soil around R0 plants regenerated from atrazine tolerant shoots andnonatrazine challenged shoots (controls) were subsequently tested in vivo foratrazine tolerance. All controls died. Seeds were collected from atrazinetolerant R0 plants. Two weeks after planting, emerged R1 seedlings were testedin vivo for atrazine tolerance as the R0 plants were. This procedure wasrepeated on the R2 plants. All nonatrazine selected control plants died whenexposed to this herbicide. Atrazine tolerant R2 plants were maintained inatrazine amended soil and appeared as healthy and vigorous as the controlgrowing in atrazine free soil.
287                                                   NAL Call. No.: QK710.P63Selective agents and marker genes for use in transformation ofmonocotyledonous plants.Wilmink, A.; Dons, J.J.M.Athens, Ga. : International Society for Plant Molecular Biology, University ofGeorgia; 1993 Jun.Plant molecular biology reporter - ISPMB v. 11 (2): p. 165-185; 1993 Jun.Literature review.  Includes references.
Language:  English
Descriptors: Monocotyledons; Genetic transformation; Selection; Marker genes;Antibiotics; Resistance; Herbicide resistance; Gene expression; Vectors;Literature reviews
288                                                    NAL Call. No.: 79.8 W41Semidominant nature of monogenic sulfonylurea herbicide resistance insugarbeet (Beta vulgaris).Hart, S.E.; Saunders, J.W.; Penner, D.Champaign, Ill. : Weed Science Society of America; 1993 Jul.Weed science v. 41 (3): p. 317-324; 1993 Jul.  Includes references.
Language:  English
Descriptors: Beta vulgaris; Herbicide resistance; Inheritance; Sulfonylureaherbicides; Chlorimuron; Semidominance; Semidominant genes; Lines;Homozygosity; Heterozygosity; Enzyme activity; Enzyme inhibitors
Abstract:  Greenhouse and laboratory studies were conducted to determine thedegree of dominance of the monogenic sulfonylurea herbicide resistance traitin diploid sugarbeet by comparing the response of homozygous and heterozygousresistant sugarbeet to primisulfuron, thifensulfuron, and chlorimuron on thewhole plant and acetolactate synthase (ALS) enzyme level. Progeny testssuggested that the monogenic sulfonylurea herbicide resistance wassemidominant. Subsequently, heterozygous resistant (R-1) and homozygousresistant (R-2) sugarbeet lines were sprayed with increasing rates ofprimisulfuron, thifensulfuron, and chlorimuron, and herbicide rates requiredfor 50% growth reduction (GR50) were determined. GR50 values were alsodetermined for homozygous susceptible sugarbeet lines (S-1 and S-2). The GR50values indicated that the R-2 sugarbeet was 377, 269, and 144 times moreresistant to primisulfuron, thifensulfuron, and chlorimuron, respectively,than susceptible S-2 sugarbeet. In contrast, R-1 sugarbeet was only 107, 76,and 57 times more resistant to primisulfuron, thifensulfuron, and chlorimuron,respectively, than S-1 sugarbeet, indicating at least a twofold difference inthe magnitude of resistance between homozygous resistant and heterozygousresistant sugarbeet lines. ALS enzyme activity analysis were consistentwithwhole plant results. Thus, based on these two, maximum crop resistance can beobtained by developing homozygous resistant cultivars.
289                                                     NAL Call. No.: 450 M99Sensitivity of field strains of Gibberella fujikuroi (Fusarium sectionLiseola) to benomyl and hygromycin B.Yan, K.; Dickman, M.B.; Xu, J.R.; Leslie, J.F.Bronx, N.Y. : The New York Botanical Garden; 1993 Mar.Mycologia v. 85 (2): p. 206-213; 1993 Mar.  Includes references.
Language:  English
Descriptors: Gibberella fujikuroi; Plant pathogenic fungi; Benomyl; Hygromycinb; Resistance; Herbicide resistance; Strain differences; Genetic regulation
290                                                    NAL Call. No.: 450 P692A serine-to-threonine substitution in the triazine herbicide-binding proteinin potato cells results in atrazine resistance without impairing productivity.Smeda, R.J.; Hasegawa, P.M.; Goldsbrough, P.B.; Singh, N.K.; Weller, S.C.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Nov.Plant physiology v. 103 (3): p. 911-917; 1993 Nov.  Includes references.
Language:  English
Descriptors: Solanum tuberosum; Cells; Selection criteria; Herbicideresistance; Atrazine; Genes; Mutations; Thylakoids; Membranes; Proteins;Quinones; Photosystem ii; Photosynthesis; Electron transfer
Abstract:  A mutation of the psbA gene was identified in photoautotrophicpotato (Solanum tuberosum L. cv Superior X U.S. Department of Agriculture line66-142) cells selected for resistance to6-chloro-N-ethyl-N'-(1-methylethyl)-1,3, 5-triazine-2,4-diamine (atrazine).Photoaffinity labeling with 6-azido-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine detected a thylakoid membrane protein with a Mr of32,000 in susceptible, but not in resistant, cells. This protein wasidentified as the secondary quinone acceptor of photosystem II (QB) protein.Atrazine resistance in selected cells was attributable to a mutation from AGT(serine) to ACT (threonine) in codon 264 of the psbA gene that encodes the QBprotein. Although the mutant cells exhibited extreme levels of resistance toatrazine, no concomitant reductions in photosynthetic electron transport orcell growth rates compared to the unselected cells were detected. This is incontrast with the losses in productivity observed in atrazine-resistantmutants that contain a glycine-264 alteration.
291                                                   NAL Call. No.: SB951.P49A similar metabolism of chlorotoluron in cell suspension cultures fromnear-isogenic susceptible and tolerant lines of wheat.Cabanne, F.; Snape, J.W.Orlando, Fla. : Academic Press; 1993 Sep.Pesticide biochemistry and physiology v. 47 (1): p. 51-59; 1993 Sep.  Includesreferences.
Language:  English
Descriptors: Triticum aestivum; Lines; Varietal susceptibility; Herbicideresistance; Metabolism; Chlorotoluron; Metabolites; Mode of action; Cellculture; In vitro
Abstract:  The metabolism of the herbicide chlorotoluron was followed in cellsuspension cultures of wheat. The cultures originated from plants of thesusceptible variety Corin, the tolerant variety Clement, and six near-isogeniclines, 9S, 10S, 16S, 17T, 18T, and 24T [susceptible (S) and tolerant (T),respectively]. The six lines had the genetic background of the susceptiblevariety Chinese Spring, but the three lines 17T, 18T, and 24T contained a genefor tolerance (Sul) transferred from the variety Cappelle-Desprez. Thecultures from Corin and Clement produced identical patterns of metaboliteswhich were also identical to those found in plants. The rate of metabolism ofthe herbicide was slightly higher in the cell culture of Clement (T) than inCorin (S), as reported for the corresponding plants. Patterns of metaboliteswere similar in the cell cultures from the six isogenic lines. The rate ofmetabolism was the same in 9S, 10S, 16S, 18T, and 24T, and lower in 17T, sothat a differential rate of metabolism was not found between T and S cellcultures. The occurrence of a differential rate of metabolism as the primarymechanism of varietal selectivity of wheat to chlorotoluron is discussed.
292                                                   NAL Call. No.: QH301.N32Site directed mutagenesis of a chloroplast encoded protein.Przibilla, E.; Yamamoto, R.New York, N.Y. : Plenum Press; 1992.NATO ASI series : Series A : Life sciences v. 226: p. 561-565. ill; 1992.  Inthe series analytic: Regulation of chloroplast biogenesis / edited by J.H.Argyroudi-Akoyunoglou. Proceedings of a NATO Advanced Research Workshop, July28-August 3, 1991, Crete, Greece.  Includes references.
Language:  English
Descriptors: Chlamydomonas reinhardtii; Genetic engineering; Mutants;Thylakoids; Herbicide resistance; Phenolic compounds
293                                              NAL Call. No.: S494.5.B563B56Somaclonal selection for tolerance to streptomycin and herbicides through ricecell culture.Kinoshita, T.; Mori, K.; Mikami, T.Berlin, W. Ger. : Springer-Verlag; 1991.Biotechnology in agriculture and forestry (14): p. 383-404; 1991.  In theseries analtyic: Rice / edited by Y.P.S. Bajaj.  Includes references.
Language:  English
Descriptors: Oryza sativa; Cell culture; Somaclonal variation; In vitroselection; Herbicide resistance; Streptomycin; Resistance; Salt tolerance
294                                                   NAL Call. No.: SB610.W39Soybean (Glycine max) cultivar tolerance to chlorimuron and imazaquin withvarying hydroponic solution pH.Newsom, L.J.; Shaw, D.R.Champaign, Ill. : The Society; 1992 Apr.Weed technology : a journal of the Weed Science Society of America v. 6 (2):p. 382-388; 1992 Apr.  Includes references.
Language:  English
Descriptors: Glycine max; Cultivars; Varietal susceptibility; Herbicideresistance; Chlorimuron; Imazaquin; Crop damage; Phytotoxicity; Ph; Nutrientsolutions; Hydroponics
295                                                   NAL Call. No.: SB610.W39Soybean (Glycine max) response to chlorimuron and imazaquin as influenced bysoil moisture.Newsom, L.J.; Shaw, D.R.Champaign, Ill. : The Society; 1992 Apr.Weed technology : a journal of the Weed Science Society of America v. 6 (2):p. 389-395; 1992 Apr.  Includes references.
Language:  English
Descriptors: Mississippi; Glycine max; Cultivars; Varietal susceptibility;Herbicide resistance; Chlorimuron; Imazaquin; Phytotoxicity; Environmentalfactors; Soil water content; Crop yield; Yield losses; Crop damage
296                                                     NAL Call. No.: S79 .E3Soybean response to quinclorac and triclopyr.Barrentine, W.L.; Street, J.E.State College, Miss. : Mississippi State University, Agricultural and ForestryExperiment Station, 1970-; 1993 Mar.Bulletin (995): 12 p.; 1993 Mar.  Includes references.
Language:  English
Descriptors: Mississippi; Cabt; Glycine max; Quinclorac; Triclopyr; Herbicideresistance; Oryza sativa; Drift; Crop yield; Field tests; Application rates;Injuries
297                                                   NAL Call. No.: QK725.P54Stably transformed herbicide resistant callus of sugarcane via microprojectilebombardment of cell suspension cultures and electroporation of protoplasts.Chowdhury, M.K.U.; Vasil, I.K.Berlin, W. Ger. : Springer International; 1992.Plant cell reports v. 11 (10): p. 494-498; 1992.  Includes references.
Language:  English
Descriptors: Saccharum; Genetic transformation; Gene transfer; Cellsuspensions; Callus; Protoplasts; Electroporation; Plasmids; Herbicideresistance
Abstract:  Stably transformed callus of a hybrid sugarcane cultivar (Saccharumspecies hybrid, CP72-1210) was achieved following high velocitymicroprojectile bombardment of suspension culture cells, and electroporationof protoplasts. A three-day old cell suspension culture (SC88) was bombardedwith gold particles coated with pBARGUS plasmid DNA containing theB-glucuronidase (GUS) reporter gene and the bar selectable gene that confersresistance to the herbicide basta. The pBARGUS plasmid was also electroporatedinto the protoplasts of another cell line (SCPP). Colonies resistant to bastawere recovered from both sources. Stable integration of the bar gene in theresistant cell lines was confirmed by Southern analysis. In addition,phosphinothricin acetyltransferase (PAT) activity was also demonstrated in thetransformed cell lines.
298                                                    NAL Call. No.: 100 F663Strategies in breeding herbicide resistant lettuce.Nagata, R.T.; Dusky, J.A.; Torres, A.C.; Cantliffe, D.J.; Feri, R.J.; Bewick,T.A.Belle Glade, Fla. : The Center; 1993 Feb.Belle Glade EREC research report EV - Florida University Agricultural Researchand Education Center (1993-2): p. 97-104; 1993 Feb.  Paper presented at theLettuce Research Workshop, February 4, 1993, Belle Glade, Florida.  Includesreferences.
Language:  English
Descriptors: Florida; Lactuca sativa; Herbicide resistance; Plant breeding;Weed control; Glyphosate; Sulfonylurea herbicides; Gene splicing; Backcrossing
299                                                    NAL Call. No.: 500 N21PStructure and topological symmetry of the glyphosate target5-enol-pyruvylshikimate-3-phosphate synthase: A distinctive protein fold.Stallings, W.C.; Abdel-Meguid, S.S.; Lim, L.W.; Shieh, H.S.; Dayringer, H.E.;Leimgruber, N.K.; Stegeman, R.A.; Anderson, K.S.; Sikorski, J.A.; Padgette,S.R.; Kishore, G.M.Washington, D.C. : The Academy; 1991 Jun01.Proceedings of the National Academy of Sciences of the United States ofAmerica v. 88 (11): p. 5046-5050; 1991 Jun01.  Includes references.
Language:  English
Descriptors: Glyphosate; Herbicide resistance; Plant physiology; Lyases; Aminoacids; Aromatic acids; Biosynthesis; Escherichia coli; X radiation
Abstract:  5-enol-Pyruvylshikimate -3-phosphate synthase (EPSP synthase;phosphoenolpyruvate:3-phosphoshikimate 1-carboxyvinyltransferase, EC 2.5.1.19)is an enzyme on the pathway toward the synthesis of aromatic amino acids inplants, fungi, and bacteria and is the target of the broad-spectrum herbicideglyphosate. The three-dimensional structure of the enzyme from Escherichiacoli has been determined by crystallographic techniques. The polypeptidebackbone chain was traced by examination of an electron density map calculatedat 3-A resolution. The two-domain structure has a distinctive fold and appearsto be formed by 6-fold replication of a protein folding unit comprising twoparallel helices and a four-stranded sheet. Each domain is formed from threeof these units, which are related by an approximate threefold symmetry axis;in each domain three of the helices are completely buried by a surface formedfrom the three beta-sheets and solvent-accessible faces of the other threehelices. The domains are related by an approximate dyad, but in the presentcrystals the molecule does not display pseudo-symmetry related to the symmetryof point group 32 because its approximate threefold axes are almost normal. Apossible relation between the three-dimensional structure of the protein andthe linear sequence of its gene will be described. The topological threefoldsymmetry and orientation of each of the two observed globular domains maydirect the binding of substrates and inhibitors by a helix macrodipole effectand implies that the active site is located near the interdomain crossoversegments. The structure also suggests a rationale for the glyphosate toleranceconferred by sequence alterations.
300                                                    NAL Call. No.: 381 J824Structure of an mdr-like gene from Arabidopsis thaliana: evolutionaryimplications.Dudler, R.; Hertig, C.Baltimore, Md. : American Society for Biochemistry and Molecular Biology; 1992Mar25.The Journal of biological chemistry v. 267 (9): p. 5882-5888; 1992 Mar25.Includes references.
Language:  English
Descriptors: Arabidopsis thaliana; Glycoproteins; Structural genes; Cloning;Nucleotide sequences; Amino acid sequences; Introns; Exons; Evolution;Herbicide resistance
Abstract:  Multidrug resistance of mammalian tumor cells is caused by theenhanced expression of P-glycoproteins. These proteins are encoded by mdrgenes and mediate the energy-dependent efflux of a variety of lipophilic drugsfrom cells. To test whether in plants mdr-like genes might be involved incertain cases of cross-resistance to different herbicides, we have cloned andcharacterized a gene from Arabidopsis thaliana, atpgp1, encoding a putativeP-glycoprotein homologue. Like the mammalian P-glycoproteins, with which itshares extensive sequence homology and a similar organization in structuraldomains, this protein is internally duplicated. Seven of the nine introns inthe atpgp1 gene match introns in the mammalian mdr genes to within a fewnucleotides, and the positions of these suggest that P-glycoprotein genesevolved by duplication and subsequent fusion of an intron-containingprimordial gene prior to the evolutionary separation of plants and mammals.The atpgp1 gene gives rise to transcripts present in all plant parts butparticularly abundant in inflorescence axes.
301                                                   NAL Call. No.: QK710.P62Structure of the amplified 5-enolpyruvylshikimate-3-phosphate synthase gene inglyphosate-resistant carrot cells.Suh, H.; Hepburn, A.G.; Kriz, A.L.; Widholm, J.M.Dordrecht : Kluwer Academic Publishers; 1993 May.Plant molecular biology v. 22 (2): p. 195-205; 1993 May.  Includes references.
Language:  English
Descriptors: Daucus carota; Structural genes; Amplification; Alkyl (aryl)transferases; Glyphosate; Herbicide resistance; Cell lines; Nucleotidesequences; Restriction mapping; Repetitive  DNA
Abstract:  The structure of amplified 5-enolpyruvylshikimate-3-phosphatesynthase (EPSPS) DNA of carrot suspension-cultured cell lines selected forglyphosate resistance was analysed to determine the mechanism of geneamplification in this plant system. Southern hybridization of the amplifiedDNA digested with several restriction enzymes probed with a petunia EPSPS cDNAclone showed that there were differences in fragment sizes in the amplifiedDNA from one highly resistant cell line in comparison with the parental line.Cloning of the EPSPS gene and 5' flanking sequences was carried out and twodifferent DNA structures were revealed. A 13 kb clone contained only one copyof the EPSPS gene while a 16 kb clone contained an inverted duplication of thegene. Southern blot analysis with a carrot DNA probe showed that only theuninverted repeated DNA structure was present in all of the cell lines duringthe selection process and the inverted repeat (IR) was present only in highlyamplified DNA. The two structures were present in about equal amounts in thehighly amplified line, TC 35G, where the EPSPS gene was amplified about25-fold. The presence of the inverted repeat (IR) was further verified by resistance to S1 nuclease hydrolysis after denaturation and rapid renaturation,showing foldback DNA with the IR length being 9.5 kb. The junction was alsosequenced. Mapping of the clones showed that the size of the amplified carrotEPSPS gene itself is about 3.5 kb. This is the first report of an IR inamplified DNA of a target enzyme gene in selected plant cells.
302                                                   NAL Call. No.: SB951.P47Structure-activity relationships of triazinone herbicides on resistant weedsand resistant Chlamydomonas reinhardtii.Oettmeier, W.; Hilp, U.; Draber, W.; Fedtke, C.; Schmidt, R.R.Essex : Elsevier Applied Science Publishers; 1991.Pesticide science v. 33 (4): p. 399-409; 1991.  Includes references.
Language:  English
Descriptors: Amaranthus retroflexus; Chenopodium album; Chlamydomonasreinhardtii; Mutants; Herbicide resistance; Herbicide resistant weeds;Atrazine; Metribuzin; Structure activity relationships; Photosystem ii;Inhibition; Wild strains
Abstract:  Weeds resistant to the s-triazine herbicide atrazine also showresistance to the triazinone herbicide metribuzin. However, with highlylipophilic triazinones, thylakoids isolated from atrazine-resistant Amaranthusretroflexus (mutation at position Ser264 of the photosystem II D-1 reactioncentre protein) in general show a higher pI(50) value in photosystem IIelectron transport than those from the wild type (i.e. negativecross-resistance; 'supersensitivity'). A quantitative structure-activityrelationship (QSAR) can be established, wherein the lipophilicity of thecompound plays a major role. In in-vivo experiments, it was found that thetriazinone DRW2698 killed resistant Amaranthus retroflexus and Chenopodiumalbum whereas the wild type was almost unaffected. Triazinones were furtherinvestigated in five different mutants of Chlamydomonas reinhardtii (mutationsin the D-1 protein at positions Ser264, Ala251, Leu275, Phe255 and Val219).Inhibitory activity of all triazinones was generally enhanced in the Phe255mutant but decreased in the Val219 mutant. In the other mutants, biologicalactivity was decreased when position 3 of the triazinone was substituted byCH3, OCH3, SCH3, NHCH3 or N(CH3)2. However, negative cross-resistance wasagain observed when this position was occupied by free thiol. It is thereforesuggested that these two groups of triazinones orient themselves differentlywithin the herbicide binding niche of the photosystem II D-1 protein.
303                                                    NAL Call. No.: 450 P692A sulfonylurea herbicide resistance gene from Arab idopsis thaliana as a newselectable marker for producti on of fertile transgenic rice plants.Li, Z.; Hayashimoto, A.; Murai, N.Rockville, MD : American Society of Plant Physiologists, 1926-; 1992 Oct.Plant physiology v. 100 (2): p. 662-668; 1992 Oct.  Includes references.
Language:  English
Descriptors: Arabidopsis thaliana; Oryza sativa; Marker genes;Oxo-acid-lyases; Mutations; Mutants; Genetic transformation; Transgenicplants; In vitro selection; Herbicide resistance; Chlorsulfuron; DirectDNAuptake; Protoplasts
Abstract:  A mutant acetolactate synthase (ALS) gene, csr1-1, isolated fromsulfonylurea herbicide-resistant Arabidopsis thaliana, was placed undercontrol of a cauliflower mosaic virus 35S promoter (35S). Rice protoplastswere transformed with the 35S/ALS chimeric gene and regenerated into fertiletransgenic rice (Oryza sativa) plants. The 35S/ALS gene was expressedeffectively as demonstrated by northern blot hybridization analysis, andconferred to transformed calli at least 200-fold greater chlorsulfuronresistance than nontransformed control calli. Effective selection of35S/ALS-transformed protoplasts was achieved at extremely low chlorsulfuronconcentrations of 10 nm. The results demonstrated that the 35S/ALS gene is analternative selectable marker for rice protoplast transformation and fertiletransgenic rice production. The results also suggest that the mutant form ofArabidopsis ALS enzyme operates normally in rice cells. Thus, the mechanism ofprotein transport to chloroplast and ALS inhibition by chlorsulfuron isapparently conserved among plant species as diverse as Arabidopsis(dicotyledon) and rice (monocotyledon).
304                                                   NAL Call. No.: SB951.P49Sulfonylurea herbicide resistance in common chickweed, perennial ryegrass, andRussian thistle.Saari, L.L.; Cotterman, J.C.; Smith, W.F.; Primiani, M.M.Orlando, Fla. : Academic Press; 1992 Feb.Pesticide biochemistry and physiology v. 42 (2): p. 110-118; 1992 Feb.Includes references.
Language:  English
Descriptors: Stellaria media; Lolium perenne; Salsola iberica; Herbicideresistance; Chlorsulfuron; Sulfometuron; Triasulfuron; Imazapyr; Biotypes;Herbicide resistant weeds; Dry matter accumulation; Resistance mechanisms;Enzyme activity; Ligases; Metabolic detoxification; Pharmacokinetics
Abstract:  Sulfonylurea herbicide resistance was demonstrated in two broadleafspecies, common chickweed (Stellaria media [L]. Vill.) and Russian thistle(Salsola iberica Sennen & Pau), and in one grass species, perennial ryegrass(Lolium perenne L.), in greenhouse tests by determining the sulfonylurea andimidazolinone herbicide rates required to reduce the dry weight accumulationof resistant and susceptible weed biotypes. The herbicide resistance in eachof the three weed biotypes was due to an acetolactate synthase (ALS) enzymethat was less sensitive to inhibition by ALS-inhibiting herbicides, includingfive sulfonylurea, one imidazolinone, and one dichlorosulfonanilideherbicides. The Km (pyruvate) and specific activity values associated with ALSisolated from the resistant biotypes were similar in magnitude to thoseobtained with ALS isolated from susceptible biotypes. Both susceptible andresistant biotypes of each weed species metabolized radiolabeled sulfonylureaherbicides at similar rates, indicating that herbicide metabolism was notcontributing to the differential plant response of the biotypes toALS-inhibiting herbicides.
305                                                      NAL Call. No.: SB1.H6Sweet corn to cultivars respond differentially to the herbicide nicosulfuron.Stall, W.M.; Bewick, T.A.Alexandria, Va. : American Society for Horticultural Science; 1992 Feb.HortScience v. 27 (2): p. 131-133; 1992 Feb.  Includes references.
Language:  English
Descriptors: Zea mays; Cultivars; Sweetcorn; Sulfonylurea herbicides;Application rates; Herbicide resistance; Varietal susceptibility; Genes;Phytotoxicity; Herbicide mixtures; Terbufos; Chlorpyrifos
Abstract:  Twelve sweet corn (Zea mays L. var. rugosa Bonaf.) cultivars weretested for response to nicosulfuron at rates of 0, 18, 36, and 72 g a.i./ha.Weight of marketable ears indicated that five cultivars were intolerant to theherbicide. Three of the cultivars that were intolerant contained theshrunken-2 endosperm mutant (sh2) and two contained the sugary enhancerendosperm mutant (se). Cultivars that were most tolerant of nicosulfuroncontained the sh2 gene. Incorporation of terbufos insecticide before plantingled to decreased marketable yield when nicosulfuron was applied at 36 g.ha-1in all cultivars tested. Chlorpyrifos insecticide incorporated before plantingdid not affect tolerance to nicosulfuron. Neither soil-applied insecticideaffected yield when nicosulfuron was not applied.
306                                                   NAL Call. No.: SB610.W39Sweet corn (Zea mays) hybrid tolerance to nicosulfuron.Morton, C.A.; Harvey, R.G.Champaign, Ill. : The Society; 1992 Jan.Weed technology : a journal of the Weed Science Society of America v. 6 (1):p. 91-96; 1992 Jan.  Includes references.
Language:  English
Descriptors: Wisconsin; Zea mays; Hybrids; Screening; Herbicide resistance;Sulfonylurea herbicides; Phytotoxicity; Growth rate; Crop damage; Varietalsusceptibility
307                                                      NAL Call. No.: HD1.A3Systems approaches to quantify crop-weed interactions and their application inweed management.Kropff, M.J.; Lotz, L.A.P.Essex : Elsevier Applied Science Publishers; 1992.Agricultural systems v. 40 (1/3): p. 265-282; 1992.  In the special issue:Systems approaches for agricultural development / edited by P.S. Teng and F.Penning de Vries. Proceedings of an international symposium held December 2-9,1991, Bangkok, Thailand.  Includes references.
Language:  English
Descriptors: Plant interaction; Pest management; Crop management; Integratedcontrol; Yield losses; Plant density; Systems approach; Simulation models;Growth models; Herbicide resistance; Weed control; Weed competition; Leaf area
308                                                   NAL Call. No.: SB610.W39Technology transfer for herbicide-tolerant weeds and herbicide-tolerant crops.Knake, E.L.Champaign, Ill. : The Society; 1992 Jul.Weed technology : a journal of the Weed Science Society of America v. 6 (3):p. 662-664; 1992 Jul.  Paper presented at the Symposium, "Development ofHerbicide-Resistant Crop Cultivars", Weed Science Society of America, February6, 1991, Louisville, Kentucky.  Includes references.
Language:  English
Descriptors: Transgenic plants; Crops; Herbicide resistance; Weeds;Biotechnology; Weed control; Technology transfer
309                                                    NAL Call. No.: 79.8 W41Terbacil and bromacil cross-resistance in powell amaranth (Amaranthuspowellii).Boydston, R.A.; Al-Khatib, K.Champaign, Ill. : Weed Science Society of America; 1992.Weed science v. 40 (4): p. 513-516; 1992.  Includes references.
Language:  English
Descriptors: Idaho; Amaranthus powellii; Biotypes; Herbicide resistance;Triazine herbicides; Cross resistance; Bromacil; Terbacil; Binding site;Thylakoids
Abstract:  A triazine-resistant Powell amaranth biotype collected in Idaho wasapproximately six times more resistant to terbacil and sixteen times moreresistant to bromacil than a normal susceptible biotype when planted intoterbacil- or bromacil-treated soil. The concentration of terbacil required toreduce photosystem II activity by 50% (I50) in isolated thylakoids was 0.24and 13.33 micromolar for the susceptible and resistant biotypes, respectively.Likewise, the I50 values for bromacil were 0.33 and 18.4 micromolar for thesusceptible and resistant biotypes, respectively. More 14C-terbacil was boundto isolated thylakoids of the susceptible than the resistant biotype withbinding constants (Kb) of 0.26 and 12.9 micromolar, respectively, indicatingthat resistance was at the chloroplast level.
310                                                    NAL Call. No.: S587.T47Tolerance of almond to herbicides.Saavedra, M.; Natera, C.London : Association of Applied Biologists : c1980-; 1993 Apr.Tests of agrochemicals and cultivars (14): p. 82-83; 1993 Apr.  Supplement toAnnals of applied biology, volume 122.  Includes references.
Language:  English
Descriptors: Prunus dulcis; Herbicides; Tolerance; Phytotoxicity;Mediterranean climate
311                                                      NAL Call. No.: SB1.H6Tolerance of apple and peach trees to triclopyr.Derr, J.F.Alexandria, Va. : The American Society for Horticultural Science; 1993 Oct.HortScience : a publication of the American Society for Horticultural Sciencev. 28 (10): p. 1021-1023; 1993 Oct.  Includes references.
Language:  English
Descriptors: Virginia; Cabt; Malus pumila; Prunus persica; Orchards; Fruittrees; Weed control; Chemical control; Triclopyr; Phytotoxicity; Crop damage;Herbicide resistance; Application rates; Glyphosate; 2,4-d
Abstract:  The tolerance of newly planted apple (Malus domestica Borkh.) andpeach [Prunuspersica (L.) Batsch] trees to the postemergence herbicidetriclopyr was evaluated in field trials. Apple and peach trees were notinjured by triclopyr applied at rates ranging from 0.28 to 1.12 kg acidequivalent (a.e.)/ha as a directed spray to soil. No injury was observedfollowing direct application of 10 ml of a triclopyr solution at 2 g a.e/literto the lower bark of either tree species. Applications of that solution to anindividual branch injured or killed the treated apple or peach branch but didnot affect the rest of the tree. No reduction in tree growth or injury wasnoted 1 year after triclopyr application. Applications of 10 ml of aglyphosate solution at 15 g a.i./liter to an apple branch caused severe injuryand a growth reduction by 1 year after application, and killed all treatedpeach trees when applied to one branch. No triclopyr or 2,4-D treatment hadaffected apple or peach trunk diameter, number of branches, or tree size 1year after application.
312                                                   NAL Call. No.: 79.9 W52RTolerance of Kentucky bluegrass seedlings to three wild oat herbicides ingreenhouse experiments.Swensen, J.B.; Dial, M.J.; Murray, G.A.; Thill, D.C.S.l. : The Society; 1993.Research progress report - Western Society of Weed Science. p. III/46-III/48;1993.  Meeting held March 9-11, 1993, Tucson, Arizona.
Language:  English
Descriptors: Poa pratensis; Herbicides; Tolerance
313                                                 NAL Call. No.: 100 L93 (3)Tolerance of rice varieties and experimental lines to rice herbicides.Sanders, D.E.; Linscombe, S.D.; Jodari, F.; Fabacher, A.P.Crowley, La. : The Station, 1986-; 1992.Annual research report / (84th): p. 89-95; 1992.
Language:  English
Descriptors: Oryza sativa; Varieties; Herbicide resistance; Application rates;Crop yield
314                                                   NAL Call. No.: SB610.W39Tolerance of three annual forage legumes to selected postemergence herbicides.Evers, G.W.; Grichar, W.J.; Pohler, C.L.; Schubert, A.M.Champaign, Ill. : The Weed Science Society of America; 1993 Jul.Weed technology : a journal of the Weed Science Society of America v. 7 (3):p. 735-739; 1993 Jul.  Includes references.
Language:  English
Descriptors: Texas; Cabt; Trifolium alexandrinum; Trifolium subterraneum;Trifolium hirtum; Fodder legumes; Weed control; Chemical control; Tolerance;Bentazone; 2,4-d; Propyzamide; Phytotoxicity; Crop damage; Abiotic injuries;Herbicide resistance; Species differences
315                                                   NAL Call. No.: 79.8 W412Tolerance of triazine-resistant and susceptible biotypes of three weeds toheat stress: a fluorescence study.Fuks, B.; Eycken, F. van; Lannoye, R.Oxford : Blackwell Scientific Publications; 1992 Feb.Weed research v. 32 (1): p. 9-17; 1992 Feb.  Includes references.
Language:  English
Descriptors: Solanum nigrum; Poa annua; Chenopodium album; Herbicide resistantweeds; Susceptibility; Biotypes; Heat stress; Heat tolerance; Chlorophyll;Fluorescence; Plant physiology
316                                                    NAL Call. No.: 450 P692Tolerance to imidazolinone herbicides in wheat.Newhouse, K.E.; Smith, W.A.; Starrett, M.A.; Schaefer, T.J.; Singh, B.K.Rockville, MD : American Society of Plant Physiologists, 1926-; 1992 Oct.Plant physiology v. 100 (2): p. 882-886; 1992 Oct.  Includes references.
Language:  English
Descriptors: Triticum aestivum; Imazethapyr; Herbicide resistance; Inducedmutations; Mutants; Genes; Inheritance; Segregation; Oxo-acid-lyases; Enzymeactivity; Allelism
Abstract:  An imidazolinone-tolerant wheat (Triticum aestivum L. em Thell)mutant in the winter wheat cultivar Fidel has been identified andcharacterized. The mutant was isolated from a population derived through seedmutagenesis of the variety with an aqueous solution containing sodium azide.Imidazolinone-tolerant wheat seedlings were selected from the generation ofthe population in the presence of imazethapyr herbicide and identified asherbicide-insensitive individuals. The trait is inherited as a singlesemidominant gene and confers high levels of tolerance to imazethapyr.Acetohydroxyacid synthase activity in extracts from imidazolinone-tolerantplants was less inhibited by imazethapyr than the enzyme from the wild type.The herbicide-tolerant plants have a completely normal phenotype and displayno negative effects on growth and yield in either the absence or presence ofimazethapyr.
317                                                    NAL Call. No.: 23 AU792Tolerances of canola, field pea, lupin and faba bean cultivars to herbicides.Lemerle, D.; Hinkley, R.B.East Melbourne : Commonwealth Scientific and Industrial Research Organization;1991.Australian journal of experimental agriculture v. 31 (3): p. 379-386; 1991.Includes references.
Language:  English
Descriptors: New South Wales; Brassica campestris; Brassica napus; Lupinusalbus; Lupinus angustifolius; Pisum sativum; Vicia faba; Cultivars; Herbicideresistance; Herbicides; Injuries; Phytotoxicity; Site factors; Weed control;Yield losses; Yield response functions
318                                                    NAL Call. No.: 450 P692Transformation and regeneration of two cultivars of pea (Pisum sativum L.).Schroeder, H.E.; Schotz, A.H.; Wardley-Richardson, T.; Spencer, D.; Higgins,T.J.V.Rockville, MD : American Society of Plant Physiologists, 1926-; 1993 Mar.Plant physiology v. 101 (3): p. 751-757; 1993 Mar.  Includes references.
Language:  English
Descriptors: Pisum sativum; Agrobacterium tumefaciens; Genetic transformation;Transgenic plants; Gene transfer; Reporter genes; Phosphotransferases;Acyltransferases; Recombinant  DNA; Regenerative ability; Tissue culture;Herbicide resistance; Glufosinate; Genetic markers; Explants; Plant embryos
Abstract:  A reproducible transformation system was developed for pea (Pisumsativum L.) using as explants sections from the embryonic axis of immatureseeds. A construct containing two chimeric genes, nopalinesynthase-phosphinothricin acetyl transferase (bar) and cauliflower mosaicvirus 35S-neomycin phosphotransferase (nptII), was introduced into two peacultivars using Agrobacterium tumefaciens-mediated transformation procedures.Regeneration was via organogenesis, and transformed plants were selected onmedium containing 15 mg/L of phosphinothricin. Transgenic peas were raised inthe glasshouse to produce flowers and viable seeds. The bar and nptII geneswere expressed in both the primary transgenic pea plants and in the nextgeneration progeny, in which they showed a typical 3:1 Mendelian inheritancepattern. Transformation of regenerated plants was confirmed by assays forneomycin phosphotransferase and phosphinothricin acetyl transferase activityand by northern blot analyses. Transformed plants were resistant to theherbicide Basta when sprayed at rates used in field practice.
319                                              NAL Call. No.: S494.5.B563B56Transformation in Linum usitatissimum L. (flax).Jordan, M.C.; McHughen, A.Berlin, W. Ger. : Springer-Verlag; 1993.Biotechnology in agriculture and forestry v. 22: p. 244-252; 1993.  In theseries analytic: Plant protoplasts and genetic engineering III / edited byY.P.S. Bajaj.  Includes references.
Language:  English
Descriptors: Linum usitatissimum; Genetic transformation; Agrobacteriumtumefaciens; Transgenic plants; Herbicide resistance; Glyphosate; Glufosinate;Gene transfer; Sulfonylurea herbicides; Regenerative ability
320                                                    NAL Call. No.: QH442.B5Transformation of sugarbeet (Beta vulgaris L.) and evaluation of herbicideresistance in transgenic plants.D'Halluin, K.; Bossut, M.; Bonne, E.; Mazur, B.; Leemans, J.; Botterman, J.New York, N.Y. : Nature Publishing Company; 1992 Mar.Bio/technology v. 10 (3): p. 309-314; 1992 Mar.  Includes references.
Language:  English
Descriptors: Beta vulgaris var. saccharifera; Agrobacterium tumefaciens;Genetic transformation; Transgenics; Gene transfer; Genes; Bilanafos; Ligases;Glufosinate; Sulfonylurea herbicides; Herbicide resistance; Acyltransferases
321                                                   NAL Call. No.: QK725.P54Transgenic herbicide-resistant Atropa belladonna using an Ri binary vector andinheritance of the transgenic trait.Saito, K.; Tamazaki, M.; Anzai, H.; Yoneyama, K.; Murakoshi, I.Berlin, W. Ger. : Springer International; 1992.Plant cell reports v. 11 (5/6): p. 219-224; 1992.  Includes references.
Language:  English
Descriptors: Atropa belladonna; Transgenics; Gene transfer; Genetictransformation; Herbicide resistance; Bilanafos; Glufosinate; Inheritance;Agrobacterium rhizogenes; Enzyme activity; Cauliflower mosaic caulimovirus;Transferases
Abstract:  Transgenic Atropa belladonna conferred with a herbicide-resistanttrait was obtained by transformation with an Ri plasmid binary vector andplant regeneration from hairy roots. We made a chimeric construct, pARK5,containing the bar gene encoding phosphinothricin acetyltransferase flankedwith the promoter for cauliflower mosaic virus 35S RNA and the 3' end of thenos gene. Leaf discs of A. belladonna were infected with Agrobacteriumrhizogenes harboring an Ri plasmid, pRi15834, and pARK5. Transformed hairyroots resistant to bialaphos (5 mg/l) were selected and plantlets wereregenerated. The integration of T-DNAs from pRi15834 and pARK5 were confirmedby DNA-blot hybridization. Expression of the bar gene in transformed R0tissues and in backcrossed F1 progeny with a non-transformant andself-fertilized progeny was indicated by enzymatic activity of theacetyltransferase. The transgenic plants showed resistance towards bialaphosand phosphinothricin. Tropane alkaloids of normal amounts were produced in thetransformed regenerants. These results present a successful application oftransformation with an Ri plasmid binary vector for conferring anagronomically useful trait to medicinal plants.
322                                                    NAL Call. No.: 450 P693Transgenic plants containing the phosphinothricin-N-acetyltransferase genemetabolize the herbicide L-phosphinothricin (glufosinate) differently fromuntransformed plants.Droge, W.; Broer, I.; Puhler, A.Berlin : Springer-Verlag; 1992.Planta v. 187 (1): p. 142-151; 1992.  Includes references.
Language:  English
Descriptors: Nicotiana tabacum; Daucus carota; Agrobacterium tumefaciens;Transgenics; Glufosinate; Metabolism; Transferases; Enzyme activity; Geneticcode; Nucleotide sequences
Abstract:  L-Phosphinothricin (L-Pt)-resistant plants were constructed byintroducing a modified phosphinothricin-N-acetyl-transferase gene (pat) viaAgrobacterium-mediated gene transfer into tobacco (Nicotiana tabacum L), andvia direct gene transfer into carrot (Daucus carota L). The metabolism of L-Ptwas studied in these transgenic, Pt-resistant plants, as well as in theuntransformed species. The degradation of L-Pt, 14C-labeled specifically atdifferent C-atoms, was analysed by measuring the release of 14CO2 and byseparating the labeled degradation products on thin-layer-chromatographyplates. In untransformed tobacco and carrot plants, L-Pt was deaminated toform its corresponding oxo acid 4-methylphosphinico-2-oxo-butanoic acid (PPO),which subsequently was decarboxylated to form 3-methylphosphinico-propanoicacid (MPP). This compound was stable in plants. A third metabolite remainedunidentified. The L-Pt was rapidly N-acetylated in herbicide-resistant tobaccoand carrot plants, indicating that the degradation pathway of L-Pt into PPOand MPP was blocked. The N-acetylated product, L-N-acetyl-Pt remained stablewith regard to degradation, but was found to exist in a second modified form.In addition, there was a pH-dependent, reversible change in the mobility ofL-N-acetyl-Pt thin-layer during chromatography.
323                                                    NAL Call. No.: QH442.B5Transgenic plants of tall fescue (Festuca arundinacea Schreb.) obtained bydirect gene transfer to protoplasts.Wang, Z.Y.; Takamizo, T.; Iglesias, V.A.; Osusky, M.; Nagel, J.; Potrykus, I.;Spangenberg, G.New York, N.Y. : Nature Publishing Company; 1992 Jun.Bio/technology v. 10 (6): p. 691-696; 1992 Jun.  Includes references.
Language:  English
Descriptors: Festuca arundinacea; Genetic transformation; Transgenics;Protoplasts; Gene transfer; Direct  DNAuptake; Reporter genes;Phosphotransferases; Acyltransferases; Cell suspensions; In vitro selection;Hygromycin b; Glufosinate; Drug resistance; Herbicide resistance; Callus;Embryogenesis; Regenerative ability
324                                                    NAL Call. No.: 500 N21PTransgenic sorghum plants via microprojectile bombardment.Casas, A.M.; Kononowicz, A.K.; Zehr, U.B.; Tomes, D.T.; Axtell, J.D.; Butler,L.G.; Bressan, R.A.; Hasegawa, P.M.Washington, D.C. : National Academy of Sciences,; 1993 Dec01.Proceedings of the National Academy of Sciences of the United States ofAmerica v. 90 (23): p. 11212-11216; 1993 Dec01.  Includes references.
Language:  English
Descriptors: Sorghum bicolor; Transgenics; Cultivars; Gene transfer; Genetictransformation; Genotypes; Herbicide resistance; Tissue culture; Transferases;Beta-glucuronidase; Enzyme activity
Abstract:  Transgenic sorghum plants have been obtained after microprojectilebombardment of immature zygotic embryos of a drought-resistant sorghumcultivar, P898012. DNA delivery parameters were optimized based on transientexpression of R and C1 maize anthocyanin regulatory elements in scutellarcells. The protocol for obtaining transgenic plants consists of the deliveryof the bar gene to immature zygotic embryos and the imposition of bialaphosselection pressure at various stages during culture, from induction of somaticembryogenesis to rooting of regenerated plantlets. One in about every 350embryos produced embryogenic tissues that survived bialaphos treatment; sixtransformed callus lines were obtained from three of the eight sorghumcultivars used in this research. Transgenic (T0) plants were obtained fromcultivar P898012 (two independent transformation events). The presence of thebar and uidA genes in the T0 plants was confirmed by Southern blot analysis ofgenomic DNA. Phosphinothricin acetyltransferase activity was detected inextracts of the T0 plants. These plants were resistant to local application ofthe herbicide Ignite/Basta, and the resistance was inherited in T1 plants as asingle dominant locus.
325                                                    NAL Call. No.: 79.8 W41Translocation of glyphosate, quizalofop, and sucrose in quackgrass (Elytrigiarepens) biotypes.Tardif, F.J.; Leroux, G.D.Champaign, Ill. : Weed Science Society of America; 1993 Jul.Weed science v. 41 (3): p. 341-346; 1993 Jul.  Includes references.
Language:  English
Descriptors: Elymus repens; Biotypes; Herbicide resistance; Herbicideresistant weeds; Glyphosate; Quizalofop; Translocation; Rhizomes; Sucrose;Uptake; Stable isotopes; Spatial distribution; Systemic action; Perennialweeds; Weed control; Chemical control
Abstract:  The translocation pattern and distribution in rhizomes of14C-glyphosate, 14C-quizalofop, and 14C-sucrose was examined in fivequackgrass biotypes. Translocation of radioactivity in the different plantparts varied among biotypes. Translocation in the whole plant after treatmentwith the three 14C-chemicals varied among biotypes but was not correlated withtheir tolerance to herbicides. Detailed analysis of distribution ofradioactivity in the primary rhizome showed that more 14C was found in theapical sections after treatment with 14C-sucrose. A similar pattern wasobserved after 14C-glyphosate application with all biotypes except one. Verylow radioactivity was found in rhizomes after 14C-quizalofop application, buta preferential accumulation in apical sections of the primary rhizome wasdetected in two biotypes. The tolerance of one biotype to glyphosate wasexplained by the absence of radioactivity accumulation in the apical sectionsof the rhizome.
326                                                   NAL Call. No.: SB610.W39Triazine-resistant common lambsquarters (Chenopodium album L.) control infield corn (Zea mays L.).Myers, M.G.; Harvey, R.G.Champaign, Ill. : The Weed Science Society of America; 1993 Oct.Weed technology : a journal of the Weed Science Society of America v. 7 (4):p. 884-889; 1993 Oct.  Includes references.
Language:  English
Descriptors: Wisconsin; Cabt; Zea mays; Weed control; Herbicide resistantweeds; Chenopodium album; Triazine herbicides; Chemical control; Applicationdate; Timing; Acetochlor; Alachlor; Atrazine; Bentazone; Bromoxynil;Cyanazine; Dicamba; Metolachlor; Pendimethalin; Pyridate; Sulfonylureaherbicides; Tridiphane; 2,4-d; Amines; Application rates; Efficacy
327                                                   NAL Call. No.: SB610.W39Triazine-resistant smooth pigweed (Amaranthus hybridus) control in field corn(Zea mays L.).Birschbach, E.D.; Myers, M.G.; Harvey, R.G.Champaign, Ill. : The Weed Science Society of America; 1993 Apr.Weed technology : a journal of the Weed Science Society of America v. 7 (2):p. 431-436; 1993 Apr.  Includes references.
Language:  English
Descriptors: Wisconsin; Cabt; Zea mays; Weed control; Chemical control;Amaranthus hybridus; Herbicide resistance; Herbicide resistant weeds;Atrazine; Metribuzin; Herbicide mixtures; Dicamba; Alachlor; Acetochlor;Pyridate; Bentazone; Cyanazine; 2,4-d; Linuron; Simazine; Sulfonylureaherbicides; Pendimethalin; Tridiphane; Application rates; Application date;Timing
328                                                     NAL Call. No.: 450 C16Tribute summer rape.Rakow, G.; Downey, R.K.Ottawa : Agricultural Institute of Canada; 1993 Jan.Canadian journal of plant science; Revue canadienne de phytotechnie v. 73 (1):p. 189-191; 1993 Jan.  Includes references.
Language:  English
Descriptors: Saskatchewan; Brassica napus; Breeding methods; Crop yield;Cultivars; Herbicide resistance
329                                                    NAL Call. No.: 450 P693Tubulin-isotype analysis of two grass species-resistant to dinitroanilineherbicides.Waldin, T.R.; Ellis, J.R.; Hussey, P.J.Berlin : Springer-Verlag; 1992.Planta v. 188 (2): p. 258-264; 1992.  Includes references.
Language:  English
Descriptors: Eleusine indica; Setaria viridis; Trifluralin; Herbicideresistance; Cross resistance; Dinitroaniline herbicides; Diagnostictechniques; Tubulin; Chemical composition; Protein content; Proteincomposition
Abstract:  Trifluralin-resistant biotypes of Eleusine indica (L.) Gaertn.(goosegrass) and Setaria viridis (L.) Beauv. (green foxtail) exhibitcross-resistance to other dinitroaniline herbicides. Since microtubules areconsidered the primary target site for dinitroaniline herbicides weinvestigated whether the differential sensitivity of resistant and susceptiblebiotypes of these species results from modified tubulin polypeptides.One-dimensional and two-dimensional polyacrylamide gel electrophoresiscombined with immunoblotting using well-characterised anti-tubulin monoclonalantibodies were used to display the family of tubulin isotypes in eachspecies. Seedlings of E. indica exhibited four beta-tubulin isotypes and onealpha-tubulin isotype, whereas those of S. viridis exhibited two beta-tubulinand two alpha-tubulin isotypes. Comparison of the susceptible and resistantbiotypes within each species revealed no differences in electrophoreticproperties of the multiple tubulin isotypes. These results provide no evidencethat resistance to dinitroaniline herbicides is associated with a modifiedtubulin polypeptide in these biotypes of E. indica or S. viridis.
330                                                    NAL Call. No.: 470 C16CUltrastructure of Chlamydomonas reinhardtii following exposure to paraquat:comparison of wild type and a paraquat-resistant mutant.Bray, D.F.; Bagu, J.R.; Nakamura, K.Ottawa, Ont. : National Research Council of Canada; 1993 Jan.Canadian journal of botany; Journal canadien de botanique v. 71 (1): p.174-182; 1993 Jan.  Includes references.
Language:  English
Descriptors: Chlamydomonas reinhardtii; Paraquat; Phytotoxicity; Herbicideresistance; Mutants; Genes; Inheritance; Ultrastructure; Mitochondria;Thylakoids; Chloroplasts; Nuclei; Methionine; Resistance
331                                                   NAL Call. No.: 79.8 W412Uptake and efflux of chlorimuron ethyl by excised soybean (Glycine max (L.)Merr.) root tissue.Nandihalli, U.B.; Bhowmik, P.C.Oxford : Blackwell Scientific Publications; 1991 Oct.Weed research v. 31 (5): p. 295-300; 1991 Oct.  Includes references.
Language:  English
Descriptors: Glycine max; Roots; Uptake; Chlorimuron; Radioactive tracers;Herbicide resistance; Susceptibility
332                                                   NAL Call. No.: SB610.W39Uptake, translocation, and metabolism of chlorimuron in soybean (Glycine max)and morningglory (Ipomoea spp.).Moseley, C.; Hatzios, K.K.; Hagood, E.S.Champaign, Ill. : The Weed Science Society of America; 1993 Apr.Weed technology : a journal of the Weed Science Society of America v. 7 (2):p. 343-348; 1993 Apr.  Includes references.
Language:  English
Descriptors: Glycine max; Cultivars; Varietal susceptibility; Ipomoealacunosa; Pharbitis hederacea; Chlorimuron; Uptake; Translocation; Metabolism;Herbicide resistance; Growth rate; Absorption; Phytotoxicity; Crop damage;Weed control; Chemical control
333                                                   NAL Call. No.: 79.8 W412Uptake, translocation and phytotoxicity of root-absorbed haloxyfop in soybean,Festuca rubra L. and Festuca arundinacea Schreb.Aguero-Alvarado, R.; Appleby, A.P.Oxford : Blackwell Scientific Publications; 1991 Oct.Weed research v. 31 (5): p. 257-263; 1991 Oct.  Includes references.
Language:  English
Descriptors: Festuca rubra; Festuca arundinacea; Glycine max; Haloxyfop;Phytotoxicity; Roots; Uptake; Absorption; Translocation; Herbicide resistance;Susceptibility; Growth rate; Radioactive tracers
334                                                      NAL Call. No.: A00109USDA scientist develops herbicide-tolerant potatoes.Washington, DC : National Biotechnology Policy Center of the National WildlifeFederation; 1991 Jun.The gene exchange v. 2 (2): p. 7; 1991 Jun.
Language:  English
Descriptors: U.S.A.; Field tests; Biotechnology; Usda; Plants
335                                                   NAL Call. No.: QK710.P62Use of bar as a selectable marker gene and for the production ofherbicide-resistant rice plants from protoplasts.Rathore, K.S.; Chowdhury, V.K.; Hodges, T.K.Dordrecht : Kluwer Academic Publishers; 1993 Mar.Plant molecular biology : an international journal on molecular biology,biochemistry and genetic engineering v. 21 (5): p. 871-884; 1993 Mar.Includes references.
Language:  English
Descriptors: Oryza sativa; Streptomyces; Genetic transformation; Transgenicplants; Protoplasts; Direct  DNAuptake; Gene transfer; Structural genes;Acyltransferases; Glufosinate; Herbicide resistance; In vitro selection;Marker genes; Reporter genes; Beta-glucuronidase
Abstract:  We have used the bar gene in combination with the herbicide Bastato select transformed rice (Oryza sativa L. cv. Radon) protoplasts for theproduction of herbicide-resistant rice plants. Protoplasts, obtained fromregenerable suspension cultures established from immature embryo callus, weretransformed using PEG-mediated DNA uptake. Transformed calli could be selected2-4 weeks after placing the protoplast-derived calli on medium containing theselective agent, phosphinothricin (PPT), the active component of Basta. Calliresistant to PPT were capable of regenerating plants. Phosphinothricinacetyltransferase (PAT) assays confirmed the expression of the bar gene inplants obtained from PPT-resistant calli. The only exceptions were two plantsobtained from the same callus that had multiple copies of the bar geneintegrated into their genomes. The transgenic status of the plants wasvarified by Southern blot analysis. In our system, where the transformationwas done via the protoplast method, there were very few escapes. Theefficiency of co-transformation with a reporter gene gusA, was 30%. The T0plants of Radon were self-fertile. Both the bar and gusA genes weretransmitted to progeny as confirmed by Southern analysis. Both genes wereexpressed in T1 and T2 progenies. Enzyme analyses on T1 progeny plants alsoshowed a gene dose response reflecting their homozygous and heterozygousstatus. The leaves of T0 plants and that of the progeny having the bar genewere resistant to application of Basta. Thus, the bar gene has proven to be auseful selectable and screenable marker for the transformation of rice plantsand for the production of herbicide-resistant plants.
336                                                    NAL Call. No.: QK710.A9The use of the Emu promoter with antibiotic and herbicide resistance genes forthe selection of transgenic wheat callus and rice plants.Chamberlain, D.A.; Brettell, R.I.S.; Last, D.I.; Witrzens, B.; McElroy, D.;Dolferus, R.; Dennis, E.S.Melbourne, Commonwealth Scientific and Industrial Research Organization; 1994.Australian journal of plant physiology v. 21 (1): p. 95-112; 1994.  Includesreferences.
Language:  English
Descriptors: Triticum aestivum; Oryza sativa; Gene transfer; Transgenicplants; Callus; Gene expression; Selection; Marker genes; Leaves; Enzymeactivity; Promoters
337                                                   NAL Call. No.: SB951.P47Using chlorophyll fluorescence induction for a quantitative detoxificationassay with metribuzin and chlorotoluron in excised wheat (triticum aestivumand Triticum durum) leaves.Ducruet, J.M.; Sixto, H.; Garcia-Baudin, J.M.Sussex : John Wiley and Sons Limited; 1993.Pesticide science v. 38 (4): p. 295-301; 1993.  Includes references.
Language:  English
Descriptors: Metribuzin; Chlorotoluron; Triticum aestivum; Triticum durum;Cultivars; Susceptibility; Herbicide resistance; Root treatment; Leaves;Translocation; Metabolic detoxification; Kinetics; Fluorescence; Induction;Dark; Incubation; Duration; Temperature; Photosystem ii; Inhibition;Quantitative techniques
Abstract:  Chlorophyll fluorescence induction was used as a probe to detectherbicide detoxification in tolerant or susceptible wheat cultivars.Experimental conditions have been carefully examined for establishingdetoxification kinetics of chlorotoluron and metribuzin, twophotosystem-II-inhibiting herbicides. After a root treatment, leaves were cut,placed in glass tubes and maintained in the dark. The fluorescence inductionrise was examined repeatedly and detoxification kinetics were established fromthese data for the same position on the individual leaves. Theherbicide-dependent fluorescence rise decreased within hours inchlorotoluron-tolerant but not in susceptible Triticum aestivum cultivars. Incontrast, no significant reversion could be detected after metribuzinapplication in both tolerant and susceptible cultivars of Triticum durum. Nearthe fluorescence-determined half-inhibition of photosystem II, lineardetoxification kinetics were obtained in individual leaves, thus providing anaccurate measurement of relative detoxification rates.
338                                                   NAL Call. No.: SB610.W39Varietal tolerance of rice (Oryza sativa) to bromoxynil and triclopyr atdifferent growth stages.Pantone, D.J.; Baker, J.B.Champaign, Ill. : The Weed Science Society of America; 1992 Oct.Weed technology : a journal of the Weed Science Society of America v. 6 (4):p. 968-974; 1992 Oct.  Includes references.
Language:  English
Descriptors: Louisiana; Cabt; Oryza sativa; Cultivars; Herbicide resistance;Varietal tolerance; Bromoxynil; Triclopyr; Application rates; Crop growthstage; Crop damage; Crop yield
339                                                   NAL Call. No.: QH301.A76Vegetation management during establishment of farm woodlands.Williamson, D.R.; MacDonald, H.G.; Nowakowski, M.R.Wellesbourne, Warwick : The Association of Applied Biologists; 1992.Aspects of applied biology (29): p. 203-210; 1992.  In the series analytic:Vegetation management in forestry, amenity and conservation areas. Paperpresented at the conference of the Association, April 7-9, 1992, University ofYork, England.  Includes references.
Language:  English
Descriptors: England; Farm woodlands; Trees; Weed control; Establishment;Ground cover plants; Herbicide residues; Herbicide resistance; Screening;Survival; Vegetation management
340                                                   NAL Call. No.: SB610.W39Weed control in oat (Avena sativa)-alfalfa (Medicago sativa) and effect onnext year corn (Zea mays) yield.Moomaw, R.S.Champaign, Ill. : The Weed Science Society of America; 1992 Oct.Weed technology : a journal of the Weed Science Society of America v. 6 (4):p. 871-877; 1992 Oct.  Includes references.
Language:  English
Descriptors: Nebraska; Cabt; Avena sativa; Medicago sativa; Zea mays;Herbicide resistance; Rotations; No-tillage; Weed control; Herbicides; Cropdensity; Crop yield; Drought
341                                                   NAL Call. No.: SB610.W39Weed thresholds: the space component and considerations for herbicideresistance.Maxwell, B.D.Champaign, Ill. : The Society; 1992 Jan.Weed technology : a journal of the Weed Science Society of America v. 6 (1):p. 205-212; 1992 Jan.  Paper presented at the "Symposium on EcologicalPerspectives on Utility of Thresholds for Weed Management," February 5, 1991.Includes references.
Language:  English
Descriptors: Weeds; Economic thresholds; Weed control; Herbicide resistance;Herbicide resistant weeds; Population dynamics; Seeds; Dispersal; Weedbiology; Crop yield; Yield losses; Mathematical models; Triticum aestivum;Setaria viridis; Simulation models
342                                                      NAL Call. No.: SB1.H6Wildflower tolerance to metolachlor and metolachlor combined with otherbroadleaf herbicides.Derr, J.F.Alexandria, Va. : The American Society for Horticultural Science; 1993 Oct.HortScience : a publication of the American Society for Horticultural Sciencev. 28 (10): p. 1023-1026; 1993 Oct.  Includes references.
Language:  English
Descriptors: Coreopsis; Leucanthemum vulgare; Echinacea purpurea; Gaillardia;Stand establishment; Weed control; Chemical control; Herbicide resistance;Site preparation; Metolachlor; Herbicide mixtures; Isoxaben; Oxadiazon;Simazine; Phytotoxicity; Abiotic injuries; Efficacy; Eclipta alba; Cyperusesculentus
Abstract:  The tolerance of transplanted lanceleaf coreopsis (Coreopsislanceolata L.), ox-eye daisy (Chrysanthemum leucantheum L.), purple coneflower[Echinaea purpurea (L.) Moench.], and blanket flower (Gaiuardia aristataPursh) to metolachlor was determined in field trials.Metolachlor at 4.5kg.ha-1 (maximum use rate) and 9.0 kg.ha-1 (twice the maximum use rate) didnot reduce stand or flowering of any wildflower species after one or twoapplications, although plants developed transient visible injury. Combiningmetolachlor with the broadleaf herbicides simazine or isoxaben resulted inunacceptable injury and stand reduction, especially in ox-eye daisy.Metolachlor plus oxadiazon was less injurious to the wildflowers thanmetolachlor plus either simazine or isoxaben. Treatments containingmetolachlor controlled yellow nutsedge (Cyperus escukntus L.) by at least 89%in both experiments. Treatments containing isoxaben controlled eclipta (Ecuptaalba L.) 100% in both studies.