bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of Combined Half‐sib and S1 Family Selection with Half‐sib, S1, and Selection Index Procedures in Maize
Authors: Goulas C. K. , Lonnquist J. H.
Published: July 2010

A combined half‐sib (HS) and Sl family evaluation procedure (HS‐S1) in a maize (Zea mays L.) population was compared with HS and S1 per se evaluation and with a selection index of the form I = b1Xl + b2X2 where X1 and X2 are grain yields of the HS and S1 families, respectively. The combined HS‐S1 evaluation resulted in lower selection differentials than either HS or S1 evaluation. Combined HS‐S1 selection in the CO (original population) identified 81, 71, and 77% of the selected families in common with HS, S1 and a selection index, respectively, and 60, 58, and 85% in CI. HS‐S1 resulted in selection of genotypes better buffered to environmental differences than either HS or $1 alone. The evidence indicates that HS evaluation results in selection of genotypes with above average population heterotic response and greater than average inbreeding depression while S1 evaluation has the opposite effect. Selection on combined HS‐S1 evaluation resulted in genotypes with less than average inbreeding depression and average or better heterotic response. The selection index has a similar effect. Expected gains showed combined HS‐S1 with resynthesis using S1 progenies to be equal to or greater than other procedures.
Genetic Male‐sterility in Wheat: Inheritance1
Authors: Jan Chao‐Chien , Qualset C. O.
Published: July 2010

UC9109‐9 is a male‐sterile common wheat (Triticum aestivum L.) that occurred as a homozygous male‐sterile F3 line from the cross of two fully fertile genotypes, D6301 and ‘Ramona 50’. UC9109‐9 can be maintained as homozygous “male‐sterile” by a low level (5%) self‐pollination. Full fertility was restored in the F1 generation of all crosses studied, including 13 common wheats of diverse origin. Inheritance studies showed that the malesterility was controlled by nuclear genes. Data from F2 and backcross generations supported a genetic model that resulted in male‐sterility only when three independent recessive ms genes were present. The cultivars ‘Rulofen’, ‘Sonora 64’, ‘Menflo’, ‘Calidad’, ‘Siete Cerros 66’, ‘Nainari 60’, ‘Lerma Rojo’, Ramona 50 and ‘Insignia’ have no ms genes; cultivars ‘Pitic 62’ and ‘Triple Dirk’ and breeding line D6301 were likely heterogeneous, having none, one, or two ms genes and ‘Onas 53’ has one ms gene. UC9109‐9 could have arisen by recombination if Ramona 50 is also heterogeneous and has plants with an ms gene. The original male‐sterile F3, appeared from a population of 140 random lines, consistent with the expectation of 1 in 64 for three genes. It is believed that at least two ms genes in UC9109‐9 trace to ‘Norin 10’, through Norin 10‐‘Brevor’, one of the parents of D6301. UC9109‐9 produces a low proportion of florets with pistilloid anthers (nonfertile); but is typical of male‐sterile wheats in other respects.
Genotypic Differences in Nitrate Absorption and Partitioning of N Among Plant Parts in Maize1
Authors: Chevalier Peggy , Schrader L. E.
Published: July 2010

The objectives of this study were to compare corn (Zea mays L.) inbreds and their F1 hybrids with respect to pattern of nitrate (NO3−) uptake during the growth period and partitioning of absorbed N among plant parts. A four‐parent (‘W64A’, ‘WI82E’, ‘A632’, ‘Oh43’), half‐diallel of corn was used. Disappearance of NO3− from solution culture was monitored from 10 days after emergence until 20 days after silking. Plants were then harvested and the distribution of total N, NO3−, and reduced N (RN) among leaf blades, leaf sheaths, stems, ears, and roots was determined.

Significant differences in NO3− uptake per plant were found among the 10 genotypes, but there was no relationship between NO3− removed by F1 hybrids and that removed by their inbred parents. Genotypic differences in dry weight, NO3− and RN per plant, and NO3− and RN còncentrations were found in all plant parts. Inbreds W64A and WI82E were especially high in NO3− and RN. Dry weight and NO3− in all plant parts, and RN in all plant parts except ears, were usually greater in hybrids than in inbreds. In general, stem NO3− concentration of the F1 approximated the mid‐parent mean. Concentration of NO3− in other plant parts of F1 hybrids was not related to that of their parents. No relationship between parents and progeny in RN concentration was found in any plant part.

In this study, genetic variation in NO3− uptake and partitioning of absorbed N was demonstrated. This variation suggests the potential for genetic improvement of NO3− uptake and N utilization by corn.
Flaming Grain Sorghum to Delay Flowering1
Authors: Vanderlip R. L. , Ball J. D. , Banks P. J. , Reece F. N. , Clark S. J.
Published: July 2010

Hybrid sorghum [Sorghum bicolor, (L.) Moench] seed production often involves parental lines that differ in maturity and which do not flower simultaneously. Flaming of sorghum plants during their early stages of development was studied to determine if that treatment would delay flowering so that both parents could be planted at one time and still flower together. Flaming significantly delayed flowering in all experiments. As severity of flaming increased, as obtained by altering speed of travel and stage of plant development at which flaming occurred, delays increased ranging from 0 to 12 days. Experiments with six parental lines indicated that each line must be tested to determine its response to severity of flaming. Both head count and yield reduction occurred when flaming severity was great enough to cause delays in half bloom of 4 to 6 days.
Leaf Photosynthetic Characteristics of Determinate Soybean Cultivars1
Authors: Bhagsari A. S. , Ashley D. A. , Brown R. H. , Boerma H. R.
Published: July 2010

Apparent photosynthesis (AP), photorespiration (Pr), transpiration (T), specific leaf weight (SLW), and diffusion resistances were measured to characterize these physiological parameters in 16 determinate soybean [Glycine max (L.) Merr.] cultivars, four each in maturity groups V through VIII. Data were obtained on 12 to 16‐day‐old terminal leaflets attached to plants grown in a greenhouse.

In three separate sets of measurements AP rates of the 16 cultivars ranged from 23 to 37 mg CO2 dm−2 hour−1 and differences among cultivars were found in each of the three measurements. Significant differences among cultivars were also observed in Pr, T, and SLW. Mesophyll diffusion resistance (rm) calculated from AP and T data also differed among cultivars. Pr not only increased as AP increased but also accounted for a higher percentage of photosynthesis in cultivars with higher Pr. AP rate was positively correlated with T and negatively correlated with laminar plus stomatal (ra+ra) diffusion resistance and with rm. The correlation of AP with SLW was significant in only one of three measurements. The determinate cultivars examined in this study display for most physiological parameters a similar range in cultivar performance as published reports for indeterminate cultivars.
Genetic Variability for Chemical Composition of Alfalfa. II. Yield and Traits Associated with Digestibility1
Authors: Hill R. R. , Barnes R. F.
Published: July 2010

Quantitative genetic parameters were estimated for first harvest yield, acid detergent fiber (ADF), acid detergent lignin, in vitro dry matter disappearance (IVDMD), and protein in ‘Saranac’ and ‘MSA‐C4’ alfalfa (Medicago sativa L.). Neutral detergent fiber (NDF) and in vitro cell wall digestibility (IVCWD) were determined in Saranac. Genotypic, phenotypic, and environmental correlations among each of the characters and with concentrations of 11 mineral elements were computed for Saranac. All estimates were obtained from analysis of a series of four, five‐parent diallel crosses and their parents in each cultivar.

Relatively large estimates of heritability were obtained for lignin (43.8%) and protein (64.4%) in Saranac, extremely low estimates were obtained for IVDMD in both cultivars (7.9% for Saranac and 6.1% for MSA‐C4). Heritabilities for the remaining characters wcre intermediate (22.0 to 33.8%). In breeding for improved nutritive value of alfalfa, selection for greater protein content or reduced ADF, NDF, or lignin content would be recommended over selection for greater IVDMD.

Estimates of genotypic, phenotypic, and environmental correlations indicated that: (1) Yield was not strongly correlated with any of the quality parameters; (2) ADF, NDF, and lignin were positively correlated with each other and negatively correlated with IVDMD and protein; and (3) IVDMD and IVCWD were positively correlated. Althongh seldom significant, most of the correlations for mineral concentration with yield, ADF, NDF, and lignin in Saranac were negative. Protein content was positively correlated with P concentration; ADF was negatively correlated with Ca, Mg, and Fe concentrations; and lignin was negatively correlated with K concentration.
Seasonal and Fertility‐Related Changes in Cottonseed Protein Quantity and Quality1
Authors: Leffler H. R. , Elmore C. D. , Hesketh J. D.
Published: July 2010

Utilization of seed protein from cotton (Gossypium hirsutum L.) as an ingredient of food products for nonruminant animals may provide producers with a salable seed commodity in addition to oil and meal. It was therefore important to establish the effects that environmental conditions migbt have on cottonseed protein quantity and quality (amino acid composition).

Cotton was grown at two levels of N fertility at each of two locations in Mississippi. At each location, N concentration was higher in cottonseed produced in high‐N N plots than in seed produced in low‐N plots. For the single harvest at Starkville, enhancement of seed N by fertilization was 1.18%. For the first five harvests at Stoneville, enhancement of seed N ranged from 0.85 to 1.10%. A stratified harvest at Stoneville enabled the identification of seasonal influences on seed size and chemical composition. Both seed size and seed N concentration decreased with later developmental periods. Seed oil concentration, however, increased with later developmental periods.

Both N fertility and seasonal patterns caused slight, but statistically significant, changes in the amino acid composition of cottonseed protein. Generally, as seed N increased, the concentrations of lysine, threonine, glycine, and alanine in the seed protein decreased; concentrations of arginine and glutamic acid increased. Because both N fertilization and seasonal factors can influence cottonseed protein quantity and amino acid composition, comparisons of these factors should be made only among environmentally similar samples.
CO2 Exchange of Subterranean Clover in Variable Light Environments1
Authors: Wilson D. R. , Fernandez C. J. , McCree K. J.
Published: July 2010

An experiment was designed to compare the CO2 balances of communities of subterranean clover (Trifolium subterraneum L.) plants exposed to variable and constant photon fluxes. Their CO2 exchange rates (CER) were monitored continuously during a 4‐day test. During 2 of those days the communities were exposed to photosynthetic photon flux densities (PPFD) which were varied over the range 0.26 to 2.00 mE(einsteins) .s−1.m−2 in a pattern that simulated the diurnal pattern of a clear day at latitude 30°. During the other 2 days the PPFD was constant at 1.20 mE.s−1.m−2. The photoperiod was 12 hours throughout. The PPFD was adjusted so that the integrated totals of CO2 taken up during the daytime (D) were identical for the two treatments. The daytime CO2 uptake patterns were different, reflecting the differences in PPFD distribution. The patterns and the totals of CO2 released during the night‐time (N) were found to be almost identical for the two treatments. Consequently, the diurnal CO2 balance (D‐N) of the plants was not affected by the different patterns of photon flux. Therefore, the normal practice in controlled environment studies of using a constant photon flux level throughout each photoperiod produces carbon balance data which are also valid in environments with variable photon fluxes.
Studies of Ethephon as a Possible Selective Male Gametocide on Tef1
Authors: Berhe Tareke , Miller Dwane G.
Published: July 2010

The gametocidal effect of ethephon (2‐chloroethyl phosphonic acid) was studied in two varieties of tef [Eragrostts tef (Zucc.) Trotter] ‘DZ‐01‐99’ and ‘DZ‐01‐186’. Foliar applications of 600, 900, and 1,200 ppm were applied three times during heading. The primary objective was to investigate if ethe~phon could be used as a substitute for hand emasculation in tef, therefore alleviating the floral sensitivity problem associated with hand manipulation of florets. All rates of ethephone reduced seed set. The lowest seed set reduction (33%) was obtained from one 600 ppm application and the highest (74%) from three 1,200 ppm applications. Reduction in seed set was not altered by artificial pollination of florets after chemical treatment. Phytotoxicity due to ethephon spray was minimal. The gametocidal effect of ethephon on male gametogenesis was first noted at the free microspore stage. Development of microspores was arrested. When pollen grains developed, they were malformed and stained poorly. In some cases, the pollen grains or anthers aborted completely.

Histological studies of ethephon‐treated florets revealed that embryo sac development was not affected up to the time of fertilization. However, soon after the megagametophyte matured into the eight‐nucleate stage and at about the time of fertilization, ovary and ovular tissue in sterelized florets underwent premature desiccation and collapse. It is assumed that this response led to female sterility since ethephon‐sterilized florets yielded no seed. Therefore, ethephon seems unsuitable for use in tel breeding. However, since conventional emasculation and pollination techniques also have not yielded hybrid seed, the induced sterility cannot be ascribed entirely to chemical application.
Intermediate Wheatgrasses of Iran1
Authors: Dewey Douglas R.
Published: July 2010

Geographic distribution, morphology, cytology, and fertility were studied in 247 collections of the intermediate wheatgrass complex (Agropyron intermedium (Host) Beauv., A. trichophorum (Link) Richt., and A. pulcherrimum Grossh.) collected in Iran and grown at Logan, Utah. This group of grasses is the most widespread Agropyron complex in Iran, occurring at altitudes of 500 to 2,700 m in the Alborz and Zagros mountain ranges and in semiarid plateau regions north of 30° N Lat. A 2,735‐plant population was extremely diverse in vegetative and spike characteristics. Plant breeders will find ample variation in these collections for significant improvement in forage and seed production. Of 234 plants, 93% had a chromosome number of 2n=42, and the remainder were 2n=41, 43, 45, and 52. Chromosome pairing at metaphase I averaged 0.60I, 20.19II, 0.05III, 0.20IV, 0.002V, and 0.008VI per cell in 1,926 cells. Pairing was in harmony with the hypothesis that intermediate wheat grasses are segmental autoallohexaploids. Open‐pollination fertility of 247 plants ranged from 0.0 to 72.8 seeds per spike and averaged 35.5. Self‐fertility of the same plants ranged from 0.0 to 44.4 seeds per spike and averaged 5.7. Occasional plants were highly self‐fertile, a condition previously unknown in these grasses. The spike characteristics that separate A. intermedium, A. trichophorum, and A. pulcherrimum taxonomically, i.e., pubescent vs. glabrous lemmas and awns vs. awnlessness, segregated in the population as if they were simply inherited traits. The three taxa cannot be separated on the basis of geographic distribution, ecological adaptation, cytological characteristics, or reproductive behavior. Consequently, all should be treated as a single species, A. intermedium.
Peroxidase Activity in Roots and Leaves of Soybeans1
Authors: Dunleavy J. M. , Urs N. V. Ramaraje
Published: July 2010

Peroxidase activity in leaves and roots of 24 soybean (Glycine max (L.) Merr.) cultivars was determined 63, 83, and 109 days after planting. Peroxidase activity in soybean leaves increased with each sampling period. The mean activity of all cultivars at 83 and 109 days was 1.8 and 5.4 times greater, respectively, than at 63 days after planting. Peroxidase activity in leaves of most cultivars varied considerably during the season.

At 63, 83, and 109 days after planting, peroxidase activity of roots was 17, 7, and 4 times greater, respectively, than in leaves. Activity in soybean roots, as in the leaves, varied considerably with the sampling periods. The mean peroxidase activity in roots was relatively high at 63 days, decreased at 83 days, and increased to 1.2 times the initial activity at 109 days. There was a much greater range between highest and lowest peroxidase activities in both leaves and roots of soybean cultivars at 63 days than at other sampling periods. When peroxidase activity in roots and leaves of five soybean cultivars each in maturity groups II, III, and IV were compared at 63, 83, and 109 days after planting, there was no relation between peroxidase activity and plant maturity.
Effects of Three Cycles of Reciprocal Recurrent Selection on the N and Plant Population Responses of Two Maize Hybrids in Kenya1
Authors: Allan A. Y. , Darrah L. L.
Published: July 2010

H611(R), a variety cross of two maize (Zea mays L.) populations improved by reciprocal recurrent selection, and H613(R), a topcross hybrid with the same male parent, were evaluated to determine if responses to N or population density had changed through three cycles of selection for yield. The evaluation was done with 40, 140, and 240 kg/ha N and 33,300, 44,400, and 55,500 plants/ha at three sites in western Kenya. Significant progress was made from selection in improving the yield of H611(R), but not H613(R). The rate of improvement of H611(R), 8.5% per cycle, agreed with past estimates. Both hybrids showed a significant (P<0.01) linear response to N and H613(R) had a significant (P<0.05) linear response to population density. The quadratic response of H611(R) to N was significant (P<0.05), that of H613(R) was not.

H611(R) showed a significantly (P<0.01) improved response to higher plant populations from cycle 0 to 3. H613(R) was found to respond more efficiently to N fertilizer than the unselected population.
Mode of Pollination and Reproduction of Meadowfoam1
Authors: Devine M. B. , Johnson J. W.
Published: July 2010

Two plant introductions, P.I. 374793 and P.I. 374800, were selected to study the mode of pollination and reproduction of the potential new oil crop, meadowfoam (Limnanthes alba Benth.). Seven pollination methods were compared in the greenhouse, utilizing the percentage of seed set for evaluation.

Pollination methods which assured either self‐ or cross‐pollination were highly effective for seed production. Methods employing undisturbed or emasculated‐isolated treatments resulted in inferior seed set. Self‐pollination and cross‐pollination were equally effective in seed production, indicating that meadowfoam was highly self‐compatible and seed from cross‐pollination could be easily obtained. The use of glycine bags to isolate artificially crossed flowers did not interfere with seed formation or development. Therefore, glycine bags can be used to isolate flowers from foreign pollen and insure controlled cross‐pollination. Observations of calyx pubescence and petal width on F1 progeny from reciprocal crosses revealed that offspring arose as a result of sexual reproduction, Limnanthes.
Population Stability of ‘Latar’ Orchardgrass as Affected by Six Diverse Seed Production Environments1
Authors: Rincker C. M. , Dean J. G. , May R. G. , Garrison C. S. , Calhoun Wheeler
Published: July 2010

Six plant characteristics of ‘Latar’ orchardgrass (Dactylis glomerata L.) were studied at Prosser, Wash., to evaluate population stability after two generations of increase at four locations in the western USA and at two locations in Japan. Populations consisting of 108 spaced plants from each of 35 increases were compared to plants from the original seed lot used at the six locations to establish the initial seed increases. The two increases made at Sapporo, Japan, did not differ from the original seed, but the six increases made at Shafter, Calif., had less spring vigor, earlier date of heading, earlier date of anthesis, fewer number of heads, shorter plant height, and less stem angle. The six increases each made at Tehachapi, California, and Aurora, Ore., differed only in stem angle. The five increases made at Nishinasuno, Japan, and the 10 increases made at Prosser differed in three plant characteristics. First‐generation seed increases tended to produce plants that were shorter, more erect, and less vigorous, with fewer heads and earlier heading and anthesis dates than plants from the original seed. Second‐generation increases continued this trend and were significantly different from the original seed in five of six characters studied.
Differences in Starch Accumulation among Dry Bean Cultivars1
Authors: Adams M. W. , Wiersma J. V. , Salazar Julio
Published: July 2010

During ontogeny, most plants store some forms of carbohydrate reserve, which may or may not be used at later stages of development (e.g., fruit growth). Little has been reported on the amount of reserve carbohydrate based on genotypic differences. The purpose of this experiment was to assess levels and changes in levels of starch stored in root and stem tissue of a diverse set of dry bean (Phaseolus vulgaris L.) cultivars in relation to seed yields. Starch associated with cultivars and stages of development was monitored with an iodine‐potassium iodide starch‐indicator solution. Starch in roots and stems varied significantly among cultivars, the range extending from undetectable amounts to abundant starch. Similarly, starch varied significantly with stage of development, usually declining as seed‐filling was completed. Significant stage × cultivar interactions occurred in both root and stem. No one pattern of change in starch was always associated with either high or low‐yielding cultivars.
Chromosome Numbers in Crambe, Crambella, and Hemicrambe1
Authors: White George A. , Solt Marie
Published: July 2010

Gametic chromosome counts were made on 15 accessions of Crambe hispanica L. including two botanical varieties, 10 accessions of C. kralikii Coss., and single accessions of Crambella teretifolia (Batt. & Trab.) Maire and Hemicrambe fruticulosa Webb. The chromosome number (n) was 30 for all accessions of C. hispanica var. hispanica from Israel, Cyprus, and Italy and n = 15 for accessions of C. hispanica var. glabrata (DC.) Coss. from Morocco, Portugal, and Spain. Three ploidy levels of n=15, 30, and 45 were found in C. kralikii. In C. abyssinica Hochst. ex R. E. Fries, a new oilseed crop, the chromosome number was n=45. The chromosome numbers of Crambella teretifolia and H. fruticulosa were determined to be n=ll and n=9, respectively.
Alfalfa Weevil Resistance Mechanism Characterized by Larval Convulsions1
Authors: Thompson T. E. , Shade R. E. , Axtell J. D.
Published: July 2010

While screening 150 alfalfa (Medicago sativa L.) introductions for resistance to the alfalfa weevil [Hypera postica (Gyllenhal)], a new resistance mechanism was discovered in P.I. 247790 from Peru. A portion of the weevil larvae reared on this introduction convulsed, dehydrated, and died before pupation. One clone produced up to 20% convulsing larvae and 40% mortality. Due to the large degree of variability for this trait in P.I. 247790, it should be possible to increase this type of antibiosis through selection.

Another resistance mechanism characterized by delayed larval development was also discovered in P.I. 247790. Larvae reared on one clone had a longer development period than those reared on other clones. This mechanism appears to have limited potential in producing resistant cultivars because development is only delayed and insects are not killed.
Productivity and Prolificacy in a Diallel Series of Market Sweet Corn Hybrids1
Authors: Younes M. H. , Andrew R. H.
Published: July 2010

The purpose of this research was to investigate the inheritance of prolificacy in a diallel series of sweet corn hybrids (Zea mays L.) and to determine the association of prolificacy with other attributes of productivity. Sweet corn has tended to be more prolific than dent corn. However, it is difficult for multiple‐eared hybrids to meet uniformity requirements for maturity, color, and kernel size because lower ears usually lag behind upper ears in development. Characters studied in addition to ears per plant (prolificacy) were percentage of usable ears, days to 90% silk, and performance rating (grade). General combining ability effects were highly significant for all characters, indicating the importance of additive gene action. Specific combining ability effects were highly significant for prolificacy, days to silk, and grade, emphasizing the importance of testing a wide range of hybrid combinations. Prolificacy was negatively associated with percentage of usable ears. Hybrids that initiated many ears had a comparatively low proportion that reached usable status. In view of this inverse relationship, selection against prolificacy is advisable in germplasm for market hybrids where productivity is measured in terms of usable ears per unit area. Use of a diallel series is well suited for evaluation purposes because all sweet corn hybrids are single hybrids involving only two parents.
Genotype ✕ Environment Interactions in Bush Bean Cultivars in Monoculture and Associated with Maize1
Authors: Francis C.A. , Prager M. , Laing D. R. , Flor C. A.
Published: July 2010

Interactions of genotypes of bush beans (Phaseolus vulgaris L.) with planting system and cropping season were evaluated on the CIAT station at 1,000 m elevation in Colombia. The objective was to determine if selection in monoculture can result in genetic progress for yield in complex multiple cropping systems. Cultivars of bush beans, defined as non‐climbing and including both determinate and indeterminate plant types, were tested in monoculture and associated with maize (Zea mays L.) in three seasons in 1975 and 1976.

Significant correlations of bean yields were obtained for these cultivars grown in monoculture and in association with maize. Higher yields and greater absolute differences among cultivars in monoculture favor this system as most efficient for early generation genotype selection and yield testing. Late generation yield evaluation of promising lines may be necessary in more than one system to evaluate adaptation to a wider range of cropping systems.

Season ✕ cultivar interactions in either system could complicate selection and rapid elimination of large numbers of progeny in a breeding program. Early generation selection for yield must be practiced with care, and most decisions on promising families delayed until replicated trial data are available from two to three generations in one location or several locations in one season.
Genotype ✕ Environment Interactions in Climbing Bean Cultivars in Monoculture and Associated with Maize1
Authors: Francis C. A. , Prager M. , Laing D. R.
Published: July 2010

Interactions of genotypes of indeterminate, climbing beans (Phaseolus vulgaris L.) with planting system and cropping season were evaluated at the CIAT location in Colombia, 1,000 m elevation and 4° N lat. Since most climbing beans in Latin America are grown in association with maize (Zea mays L.), the objective was to determine whether selection of beans in monoculture would be a valid approach to genetic improvement. Climbing bean cultivars were tested in monoculture and associated with maize in three seasons in 1975 and 1976.

Significant correlations for yields were obtained for the cultivars tested in association with maize and in monoculture in two seasons (r=0.90, r=0.81). Bean yields averaged 2,200 kg/ha in monoculture and 680 kg/ha in association over three seasons, with coefficients of variation of 15.2 and 22.5%, respectively. Higher yields, more precise evaluation of differences among cultivars, and significant positive correlations with associated crop yields favor the monocrop system as most efficient for early generation selection and testing of climbing beans.

Season ✕ cultivar interactions in both planting systems could complicate selection for broad adaptation and confident early generation selection in a breeding program. This early selection should concentrate on qualitative traits such as disease and insect resistance, seed color, and desired maturity, with decisions on yield potential delayed until replicated trials in more than one season or more than one location provide adequate evaluation of yield.
Allele Determining Rugate Fruit Surface in Cotton1
Authors: Lee Joshua A.
Published: July 2010

Rugate fruit surface in cotton (Gossypium hirsutum L.) is accompanied by dense glandulosity and correlates with increased terpenoid aldehyde level in flower buds. Rugate carpellary surface is determined in M. J. Lukefahr's XG‐15 line by the allele Glr 3 in the homozygous state acting in conceit with an array of other gland‐determining alleles at other loci. A sister line, 3‐T, is homozygous for Gl3, an allele having little or no capacity to impart rugate fruit surface. Glr 3 was transferred to two stocks of G. barbadense L. where the allele also produced densely glanded, rugate fruit surface.
Nitrate Reductase Assays as a Prediction Test for Crosses and Lines in Spring Wheat1
Authors: Deckard E. L. , Busch R. H.
Published: July 2010

The in vitro and in vivo nitrate reductase (NR) activity of four high and four low yielding hard red spring wheat (Triticum aestivum L.) parents and the highest and lowest yielding F7 lines from each of 25 crosses were determined under growth chamber and field conditions. Ranking of genotypes was more consistent between the two sampling dates in the field or between growth chamber samples and field samples for the in vitro assay than the in vivo assay. Except for the parental seedling activities, the in vitro and in vivo activities were not significantly correlated.

The mid‐parent values for NR activity significantly predicted those crosses that produced a higher frequency of high yielding lines. However, the highest yielding line within a cross could not be differentiated from the lowest yielding line on the basis of NR activity by either assay method. Also, the NR activity (in vitro and in vivo) of the lines from all crosses was not significantly correlated with yield of grain or grain protein. The relationship between in vitro NR activity and yield of grain or grain protein was improved if crosses involving the more diverse genotypes were deleted, but significant relationships generally were not obtained. The grain protein yields and reduced N partitioning data indicated that the NR values obtained in this experiment were not closely related to the genotypic ability to accumulate reduced N under field conditions. The reason for this remains unclear.
Sensitivity of Ion Accumulation by Cucumber Seedlings to Nitrapyrin and to 6‐Chloropicolinic Acid1
Authors: Zawistowska Teresa , Barker A. V. , Glover L. J.
Published: July 2010

Certain plants, such as cucumber (Cucumis sativus L.), are very susceptible to growth restrictions and aberrations induced by nitrapyrin, a nitrification inhibitor, or by its metabolite, 6‐chloropicolinic acid (PCA). Injuries produced by these materials closely resemble those caused by growth regulator substances, which are known to affect cell membrane permeability and ion uptake. Because ion uptake may be similarly affected by nitrapyrin or PCA, this study was undertaken to investigate the effects of these chemicals on NO3− C1−, K+ and Ca++ absorption by cucumber.

Two‐week‐old plants were grown in growth chambers using nutrient solutions with nitrapyrin or PCA added during a treatment period which ranged from 30 to 96 hours. Relative to untreated controls, NO3−, K+, and Ca++ absorptions were restricted 24, 17, and 25%, respectively, by nitrapyrin and 52, 36, and 28% by PCA at 5.0 x 100M. Likewise, relative chloride absorption was doubled by nitrapyrin and more than quadrupled by PCA.

It was suggested that nitrapyrin and PCA affect ion uptake by altering membrane permeability in a fashion similar to that proposed for auxin types of compounds.
Effect of Pea Seed Genotype on Preemergence Damping‐Off and Resistance to Fusarium and Pythium Root Rot1
Authors: Muehlbauer F. J. , Kraft J. M.
Published: July 2010

Pea (Pisum sativum L.) lines, isogenic for the major A gene in various combinations with the genes F, Pl, M, I, and R were developed and tested for emergence and root rot resistance in soils infested with Fusarium and Pythium. Lines homozygous for A had significantly better emergence than a counterparts, presumably due to the fungistatic effects of phenols associated with anthocyanin pigmentation. Significantly lower root rot scores were noted in one test for the A isolines as compared to their a counterparts. The M gene appeared to give better emergence in the presence of either A or a Genes F, M, I, and R in the presence of A and a had a cumulative effect in reducing scores for pre‐emergence damping‐off and root disease.
Production, Fiber Quality, and Ginning Performance of Low and High Pubescent Pima Cotton1
Authors: Young E. F. , Kirk I. W. , Feaster Carl V.
Published: July 2010

A high pubescent Pima (Gossypium barbadense L.) cultivar that has high yield potential and adequate fiber properties was identified and evaluated. Performance testing and fiber quality evaluation were obtained while developing these cottons. The high pubescent cultivar was found to have greater amounts of trash in the seed cotton samples after normal cleaning than low pubescent commercial cultivars. A ginning study was conducted to determine the effectiveness of two seed cotton cleaning treatments for removal of trash from the high pubescent, experimental cultivar and a low pubescent, commercial cultivar. A moderate seed cotton cleaning system was adequate for cleaning the low pubescent Pima cotton, but an elaborate seed cotton cleaning system was required for obtaining acceptable grades of the high pubescent Pima cotton, —
A Method for Detecting Genetic Variability for Grass Tetany Potential in Tall Fescue1
Authors: Haaland R. L. , Elkins C. B. , Hoveland C. S.
Published: July 2010

Seedlings of ‘Kentucky 31’ and open‐pollinated progeny from three genetically diverse tall fescue (Festuca arundinacea Schreb.) clones were screened for Mg and K concentrations at 2% and 21% rhizosphere 02 in sand cultures. Using six watertight and airtight boxes, 15 x 9 X 30 cm, filled with washed sand, 27 seedlings of each entry were grown in three replications at low (2%) and high (21%) rhizosphere 02 in the greenhouse. Magnesium uptake of tall fescue was reduced at low (2%) rhizosphere 02. Seedlings grown at 2% 02 ranged from 0.13 to 0.36% Mg and from 1.4 to 3.3% K. Both Mg and K concentrations were lower at 2% 02 than at 21% 02. Eight genotypes selected to represent a range in Mg and K levels at low 02 were grown past the seedling stage, vegetatively propagated into a soil culture, and evaluated for Mg and K at 2 and 21% rhizosphere 02. A genotype selected for high Mg concentration at low 02 remained high in Mg at both low and high 02 in soil during a subsequent experiment. Low Mg genotypes remained low in Mg when grown in soil. All K levels were very high when older tissue was evaluated in soil. If plants with high Mg and low K can be identified and if the characteristic is heritable, tall fescue with low grass tetany potential could be developed.
Nullisonmic‐Tetrasomic Wheat for Agronomic and Nutritional Studies1
Authors: Tucic Branka , McGuire P. E. , Qualset C. O. , Kasarda D. D.
Published: July 2010

Chromosomes of Triticum aestivum L. homoeologous groups 1 and 6 have genes coding for synthesis of the endosperm gliadin components. A‐gliadin, coded by genes on chromosome 6A, and possibly other gliadins, produce symptoms in humans with celiac disease. It may be possible to eliminate toxic proteins through breeding. As a first attempt, nullisomic 6A‐tetrasomic 6B (N6AT6B) and N6A‐T6D limes of cultivar ‘Chinese Spring,’ which do not produce A‐gliadin, were grown in sufficient quantities for human feeding trials. Both lines produced satisfactory yields of grain for specialty uses. N6A‐T6B was more desirable agronomically and produced less agliadins than N6A‐T6D. Fertility of the N‐T lines was only slightly lower than that of Chinese Spring.
Mechanical System for End‐Trimming Soybean Plots1
Authors: Freed J. C. , Bahrenfus J. B. , Bandstra T. J. , Fehr W. R. , Clark R. C.
Published: July 2010

A mechanical end‐trimmer was developed to cut soybean [Glycine max (L.) Merr.] plots to a uniform length. It consists of two self‐propelled rotary mowers connected at a desired distance by a horizontal pipe clamped to a frame added to each mower. Two persons are needed to operate the end‐trimmer, one for each mower. The end‐trimmer is driven across plots perpendicular to the direction of the rows, and final plot length is determined by the distance between the mowers. The end‐trimmer works best when lodging is not excessive and when seed formation is not advanced. With this method, two persons can trim approximately 1,500 four‐row plots per day, compared with 400 plots per day by use of hand methods.
Inheritance of Protein and Lysine in Three Wheat Crosses1
Authors: Diehl A. L. , Johnson V. A. , Mattern P. J.
Published: July 2010

Inheritance of grain protein and lysine in three wheat (Triticum aestivum L.) crosses was investigated. Three high‐protein wheat cultivars, ‘April Bearded’, ‘Atlas 66’ and ‘Nap Hal’ were crossed in diallel fashion without reciprocals. Spaced plants of the parental, F1, F2, and backcross generations for each cross were grown at Yuma, Arizona, and Fort Collins, Colorado, in 1973. Grain protein was significantly higher for Nap Hal than for April Bearded and Atlas 66 at Yuma. Grain proteins of April Bearded and Atlas 66 were not significantly different at Yuma. At Fort Collins the grain protein of Atlas 66 significantly exceeded that of April Bearded and Nap Hal. No differences were measured for grain protein between April Bearded and Nap Hal at Fort Collins. Additive genetic effects for protein were detected although protein means of F1 hybrids were always below midparent values and near or below the low‐protein parent. F2 means approached the midparent values for protein. Backcross performances indicated April Bearded and Nap Hal may have protein genes in common. Nap Hal and April Bearded produced significantly more lysine (percent of protein) than Atlas 66 at both locations. At Yuma, lysine was significantly higher for Nap Hal than for April Bearded. The F1 and F2 means for lysine (percent of protein) approached midparent values, indicating possible additive genetic effects. Environmental variances estimated by plant‐to‐plant variances of nonsegregating populations were often larger than were among‐plant variances in segregating populations. Genotype ✕ environment interactions for protein and lysine were significant.
Seasonal Emanation of Ocimene from Alfalfa Flowers with Three Irrigation Treatments1
Authors: Loper Gerald M. , Berdel R. L.
Published: July 2010

Alfalfa (Medicago sativa L.) requires cross‐pollination for economic seed production. In the arid Southwest, honeybees (Apis mellifera L.) are relied on for this pollination. The studies reported in this paper were conducted to better understand the plant and honeybee dynamics during the alfalfa pollination period. Emanation patterns of volatiles from alfalfa flowers were studied by gas chromatography during the summer seasons of 1973, 1974, and 1975. Irrigation treatments and cutting dates were varied, and observations of honey bee visitation, flowering, and plant water potential were made. Several emanation patterns of flower volatiles were noted: 1) daily aroma maxima occurred between 1100 and 1400 hours, depending on cloud cover and rainfall, 2) the June blooming period produced the highest amounts of volatiles/ flower compared to May, August, and September (gradually decreasing from June through September), and 3) a “burst” of volatiles (emanation/flower) that lasted 3 to 4 days occurred during early June each year. Irrigation treatments did not affect the amount of volatiles produced during the “burst” although adequate moisure tended to keep the volatiles/flower readings higher than the dry treatment after the “burst.” The volatile “burst” may be related to a physiological “climacteric” occurring when the alfalfa plant has changed from a vegetative to reproductive state. Plant water potential and honeybee counts were not well correlated with volatile emanation changes.
Comparison of Methods for Evaluating Stalk Strength of Sorghum1
Authors: Schertz K. F. , Al‐Tayar F. A. , Rosenow D. T.
Published: July 2010

Stalk breakage prior to harvest is a cause of grain loss in sorghum [Sorghum bicolor (L.) Moench] and is deterrent to the use of taller, higher yielding hybrids. Laboratory methods of evaluating stalk strength in sorghum were assessed by comparing them with field stalk breakage for the purpose of developing a procedure useful in breeding programs. For each test method there were significant differences among lines for stalk strength at each of the four positions tested. Stalk strengths at the base of the plant as determined by crushing, penetration, and bending tests were significantly and negatively correlated with total stalk breakage in the field. Strenghts of the peduncle as determined by shearing and bending tests were correlated significantly and negatively with breakage of peduncles in the field. Of the six methods evaluated, penetration of non‐dried stalks was the least variable as indicated by coefficients of variability.
Feedback Regulation of Lysine, Threonine, and Methionine Biosynthetic Enzymes in Corn1
Authors: Gengenbach B. G. , Walter T. J. , Green C. E. , Hibberd K. A.
Published: July 2010

The first three enzymes in the branched pathway for lysine, threonine, isoleucine, and methionine biosynthesis from aspartate were studied in five corn (Zea mays L.) tissues. Extracts from 3‐day‐old etiolated shoots and roots of inbred W23, W23 kernels 22 days after pollination, and callus cultures and suspension cell cultures of ‘Black Mexican Sweet’ contained aspartokinase, aspartate semialdehyde dehydrogenase, and homoserine dehydrogenase activities. Low (0.02 to 0.1 mM) lysine levels inhibited aspartokinase from each tissue and 0.025 to 0.25 mM threonlne inhibited homoserine dehydrogenase. Maximum threonine inhibition of homoserine dehydrogenase varied from 23 to 71% among tissues. Similar threonine‐sensitive homoserine dehydrogenase isozymes were found in crude extracts of each tissue. Combinations of lysine and threonine did not increase inhibition of either aspartokinase or homoserine dehydrogenase. Aspartate semialdehyde dehydrogenase of the callus and suspension culture extracts, but not the other extracts, was inhibited by 10 mM methionine; lysine and threonine were only slightly inhibitory alone or in combination. Conversion of aspartate to homoserine in vegetative and kernel tissues of corn thus is primarily feedback regulated by lysine at the first step, aspartokinase, and by threonine at the third step, homoserine dehydrogenase.
Inheritance of Gossypol Level in Gossypium. IV. Results from the Reciprocal Exchange of the Major Gossypol‐Gland Alleles Between G. hirsutum L. and G. barbadense L.1
Authors: Lee Joshua A.
Published: July 2010

Cultivars of Gossypium barbadense L. commonly assay 2.00 to 2.50% terpenoid aldehydes (gossypol and methoxgossypol) in dried meals from whole seeds, whereas Upland cultivars of G. hirsutum L. commonly average 1.00 to 1.50%.G landlesss eeds of both species are virtually free of gossypol. Using glandless stocks as recipient parents, the gossypol‐gland alleles of the two species, Gl2 and Gl2 were exchangedr eciprocally using the G. hirsutum cultivar, ‘Empire’, and the G. barbadense stock, AS‐2 Sea Island, as donors. AS‐2 made homozygous for alleles from Empire averaged about the same level of gossypol in seeds as the control (2.06% vs. 2.10%). Empire made homozygous for AS‐2 alleles likewise stabilized near its control (1.20% vs. 1.23%). Neither of the introgresseed monomeric stocks (Gl2Gl2gl3gl3 and gl2gl2Gl3Gl3) showed parity of expression between the gossypol‐gland alleles characteristic of “pure” G. barbadense. Rather, both showed the G. hirsutum type of expression wherein the Gl2 monomeric stores 2.5 to 3.0 times as much terpenoid substances as the Gl3 monomeric The high‐terpenoid G. hirsutum stock, however, 3‐T, showed a nearparity level of the substances between its monomerics after introgression with AS‐2 alleles. No cytoplasmic effects were detected.
Field Tolerance in Alfalfa to Sclerotinia Crown and Stem Rot1
Authors: Welty Ronald E. , Busbice Thad H.
Published: July 2010

Alfalfa (Medicago sativa L.) cultivars and experimental lines were evaluated in two replicated field tests for Sclerotinia crown and stem damage caused by natural infection. In both experiments the amount of damage that occurred in the entries differed significantly. When the disease was most severe, the amount of damage among entries ranged from 2 to 30%. The results of the two field experiments were consistent (r = 0.87, 11 d.f.). A diseasetolerance reaction that was observed in the field was not found in greenhouse experiments. Differences in field tolerance may have been related to the degree of general adaptation of the cultivars and lines to the test location and to subtle differences in susceptibility to initial infection.
An Unexpected Cause of Poor Germination and Emergence of Wheat1
Authors: O'Brien L. , Orth R. A.
Published: July 2010

Germination and emergence of wheat (Triticum aestivum L.) were shown to be reduced following storage on particleboard. The germination reducing agent is suspected to be free formaldehyde, which is released from the bonding resin during production and usage. Seed to be stored on particleboard shelving should be stored in glass vials or tins.
Strain‐Specific Ineffective Nodulation of the Tropical Legume Desmodium by Rhizobium1
Authors: Pinchbeck B. R.
Published: July 2010

The Rhizobium strain CB1789 originally isolated from Desmodium sandwicense E. Mey produces a strainspecific ineffective nodulation response with several lines of D. aparines (Link) D. C. Study of F2 and backcross populations from D. sandwicense ✕ D. aparines hybrids provided evidence for segregation of a dominant gene at a single locus conditioning ineffective nodulation in D. aparines. The D. aparines lines expressing ineffective nodulation are used in commerce.
Comparison of Seed and Fiber Properties and Yield of Glanded and Glandless Cottons1
Authors: Halloin J. M. , Turner J. H. , Hoskinson P. E.
Published: July 2010

Yield, fiber, and seed properties were compared between nine pairs of glanded and glandless cottons (Gossypium hirsutum L.). Three replicates of paired‐row plots were planted at Jackson, Tennessee, in 1975. On the average, seedcotton yield was less in glandless than in glanded cottons, possibly a result of poor adaptation of some lines to the location. Among other properties, the only important difference found between glanded and glandless cottons, as groups, was in lint percentage. The higher lint percentage of the glandless entries appeared to relate to their smaller seed size.