bluuebunny/crossref_metadata_2025_split huggingface dataset:
DEGRADATION OF SEVERAL HERBICIDES IN A SOIL PREVIOUSLY TREATED WITH MCPA
Authors: KIRKLAND K. , FRYER J. D. 
Published: July 2006

Summary. Soil which had received nine previous field treatments of MGPA (33 kg/ha) at intervals of about 6 months, and which had become able to detoxify MCPA more rapidly than untreated control soil, was able to degrade MCPB with equal facility. In contrast, the disappearance rates of phytotoxic residues of dichlorprop (2‐(2,4‐dichloro‐phenoxy)propionic acid), mecoprop (2‐(4‐chloro‐2‐methylphenoxy)propionic acid), fenoprop (2‐(2,4,5‐trichlorophcnoxy)propionic acid) and dicamba (2‐methoxy‐3,6‐dichlorobcnzoic acid), as determined with a bioassay technique, were unaffected by previous treatments of the soil with MCPA.Indirect evidence from these studies suggests that β‐oxidation of MCPB to MCPA did not occur to any significant extent either in the soil to which the roots of the indicator plant were exposed or in the roots themselves.Dégradation de quelques herbicides dans un sol préddenvnent traté avec le MCPARésumé. Un sol ayant reçu 9 traitements au MGPA (3,3 kg/ha) à des intervalles d'environ 6 mois et qui est devenu capable de dégrader le MCPA plus rapidement qu'un téntoin non traité, s'est montré capable de diégrader le MGPB avec la mêmefacilité. En revanehe, les taux de disparition de résidus toxiques déterminés par des testsbiologiques, du dichlorprop (acide 2‐(2,4‐dichlorophenoxy)propionique), du mécoprop(acide 2‐(4‐chloro‐2‐méthylphénoxy)propionique), du fénoprop (acide 2‐(2,4,5‐trichlorophénoxy)propionique) et du dicamba (acide 2‐méthoxy‐3,6‐dichlorobenzoique) n'ont pas été affectés par les traitements antérieurs avec le MCPA.Comme conclusion indirecte de ces travaux il est suggéré que la β‐oxydation du MGPB en MCPA ne se produit pas à un dcgré significatif dans le sol où les racines desplantes servant d'indicateurs sont plongées, pas plus que dans les racincs elles‐mêmes.Abbau von verschiedenen Herbiziden in einem vorher mit MCPA behandelten BodenZusammenfassung. Boden, der auf dem Feld in Abstanden von sechs Monaten neunmal mit MGPA (3,3 kg/ha) behandelt wurde und dadurch in der Lage war, MGPA schneiler umzuwandeln als der unbchandelte Kon troll boden, konnte MCPB gleichermassen abbauen. Mit Hilfe von Biotests wurde ermittelt, dass vorausgehende Behandlungen des Bodens mit MCPA dagegen keinen Einfiuss auf die Abbaurate phytotoxischer Rückstände von Dichlorprop (2‐(2,4‐Dichlor‐phenoxy)‐propionsäurc), Mecoprop(2‐(4‐Ghlor‐2‐methyl‐phenoxy)‐propionsäure), Fenoprop (2‐(2,4,5‐Trichlorphenoxy)‐propionsaure) und Dicamba (3,6‐Dichlor‐2‐methoxy‐benzoesaure) hatten.Die Ergebnisse lassen darauf schliessen, dass der β‐Oxidation von MCPB zu MGPA weder im Boden, dem die Wurzein der Testpflanzen ausgesetzt waren, noch in den Wurzeln selbst Bedeutung zukam.
EVOLUTION COMPARATIVE DE LA FLORE ADVENTICE AVEC OU SANS DESHERBAGE CHIMIQUE
Authors: BARRALIS G. 
Published: July 2006

Résumé. Sur un assolement quadriennal a étéétudié l'évolution de la flore adventice au cours d'une année culturale et au cours d'une rotation cullurale complète. Les plantules apparues en avril ne représentent que 7,4% en moyenne pour les cultures d'automne et 28,7% en moyenne pour les cultures de printemps, du nombre de semences viables susceptibles dc germer à cettc date; ces icvées ne représentent que 5,6% en moyenne du stock total de graines viables contenues dans les 10 premiers centimétres de sol. Aprèes 5 années de désherbage, la flore adventice mesurée par le nombre de plantules apparuea en avril avant les traitements herbicides montre une très grande stabilité tant qualitative que quantitative; seules les espéces vivaces se sont considérablement dévelopées les parodies non désherbées.Vergleich der Entwicklung einer Unkraulflora mit und ohne chemischer Unkrautbekämpfung
TRANSLOCATION OF 14C‐ASSIMILATES AND 3‐AMINO‐1,2,4‐TRIAZOLE AND ITS METABOLITES IN AGROPYRON REPENS
Authors: FIVELAND T. J. , ERICKSON L. C. , SEELY C. I. 
Published: July 2006

Summary. Translocation of 3‐amino‐1,2,4‐triazole‐5‐14C (14C‐aminotriazole) was compared to that of 14C‐assimilates in couch grass (Agropyron repens (L.) Beauv.) at three different growth stages.Assimilates of 14CO2 were translocated from the treated shoot to other shoots and rhizomes at the 2–3‐leaf and 3–4‐leaf stages of development. Much less labelled material was translocated into untreated shoots at the 5‐leaf stage. More 14C‐assimilates were translocated to the roots than to untreated shoots at all developmental stages. The translocation patterns of 14C‐aminotriazole and 14C‐assimilates were similar.Two metabolites, A and B, were formed from 14C‐aminotriazole, which chromatographed identically to previously described metabolites in Cirsium arvense (L.) Scop. A was further metabolized into B. Labelled aminotriazole and its two metabolites were translocated throughout the plants. Metabolite A was phytotoxic when concentrated and re‐applied to couch grass, but its properties were not those of Unknown II from Cirsium arvense. They were the same as those of Unknown III. Whether or not metabolite A and Unknown III are identical was not established. Migration des substances assimilables marquées au
14
C, du 3 amino‐1,2,4‐triazole et de ses métabolites chez Agropyron repens
EFFECT OF GROWTH REGULATORS AND HERBICIDES ON NORMAL AND WOUND PERIDERM ONTOGENY IN FRAXINUS PENNSYLVANICA SEEDLINGS*
Authors: BORGER G. A. , KOZLOWSKI T. T. 
Published: July 2006

Summary. IAA, GA, kinetin, 2,4‐D and naptalam were applied at 100 or 1000 ppm in lanolin to wounds made at the top of the hypocotyl of Fraxinus pennsylvanica Marsh. seedlings. Formation of normal periderm was prevented in the hypocotyl below the wounded tissue by 1000 ppm IAA or naptalam and 100 or 1000 ppm 2,4‐D. IAA or naptalam at 100 ppm and GA or kinetin at 100 or 1000 ppm retarded normal periderm development. Wound periderm development was prevented only by 1000 ppm 2,4‐D. Wound‐stimulated development of normal periderm in tissues near the wound was prevented by 1000 ppm kinetin and 100 or 1000 ppm 2,4‐D. Anomalous growths which appeared morphologically similar to nascent roots developed in the wounded hypocotyl section of seedlings treated with 1000 ppm naptalam and 100 or 1000 ppm 2,4‐D. Identical growths were found in unwounded portions of the hypocotyl of seedlings treated with 100 or 1000 ppm 2,4‐D. The data emphasize differences in physiological control of normal and wound periderm development. Effets de substances de croissance et d'herbicides sur l'onlogénie du pérderme normal ou blessé dans des plantules de Fraxinus pennsylvanica.
SOME HISTOLOGTCAL EFFECTS OF DIRECT CONTACT OF PINUS RESINOSA SEEDS AND YOUNG SEEDLINGS WITH 2,4,5‐T*
Authors: WU CHING CHEN , KOZLOWSKI T. T. 
Published: July 2006

Summary. Direct contact of seeds and recently emerged seedlings with 2,4,5‐T at 25 or 100 ppm caused abnormal development of Pinus resinosa Ait. seedlings. The first observed effect of 2,4,5‐T treatment at 25 ppm was cessation of cell division and expansion in the roots. Subsequently the herbicide stimulated proliferation and expansion of parenchyma ceils in the stem and cotyledons, causing abnormal thickening of the seedlings. Parenchyma cells in the upper stem became disorganized and many of them collapsed. Callus tissue then formed in the region of tissue disintegration. The herbicide also inhibited formation of primary needle primordia and expansion of primary needles. In treated plants the cotyledons were fused to primary needles. Cell proliferation and formation of callus tissue were greater with 2,4,5‐T at 100 ppm than at 25 ppm. Quelques effets histologiques du contact direct des semences et desjeunes plantules de Pintis resinosa avec le 2,4,5‐T
WEED COMPETITION IN TRANSPLANTED SPRING CABBAGE
Authors: LAWSON H. M. 
Published: July 2006

Summary. The presence of weeds during autumn and winter had no effect on the growth of transplanted spring cabbage provided they were removed before rapid growth of crop and weeds began in early spring. Weeds left beyond this time competed with the crop, resulting in smaller marketable heads. Increasingly severe competition affected internal head quality, reduced the numbers of plants producing heads and resulted in the death of a proportion of the crop plants. The main weed species responsible for crop loss was Stellaria media, which survived winter frosts and grew rapidly in early spring to fill all available ground space, dominating the weed flora and shading the crop foliage.Application of propachlor at planting time failed to give sufficient control of S. media to avoid crop loss, although the onset of competition was delayed. Trifluralin gave excellent control of S. media and resistant species were kept in check by the crop.Comparison of cropped and uncropped plots showed that the crop exerted considerable competitive pressure on the growth and development of weeds particularly where this had been reduced or delayed by herbicide treatment. The presence or absence of the crop did not, however, affect the relative proportions of the weed species, except on plots treated with trifluralin, where the crop suppressed Capsella bursa‐pastoris. Compétition des mauvaises herbes dans les choux de printemps repiqués
SELECTIVE ACTION OF TRIAZINES FOR CONTROL OF WILD CANARYGRASS IN WHEAT
Authors: ESHEL Y. 
Published: July 2006

Summary. The selective action of triazine herbicides for control of wild canarygrass (Phalaris spp.) in wheat was studied in four field experiments. Canarygrass was controlled by pre‐ and post‐emergence applications of methoprotryne and terbutryne. The phytotoxicity of methoprotryne to wheat was higher than that of terbutryne. Addition of small amounts of simazine to either one of the methylthiotriazines considerably increased damage to wheat. The most resistant stage of wheat after emergence was that of spike initiation, whereas the most sensitive stage was that of earing. Increase of yield as a result of control of canarygrass was higher in semi‐dwarf wheat than in normal‐height cultivars. Application of 625 g/ha of terbutryne to a semi‐dwarf cultivar pre‐ and post‐emergence increased grain yield by 56% and 29%, respectively. Action selective des triazines pour la lutte contre les Phalaris dans le blé
THE HYDROLYSIS OF 2,4‐DICHLOROPHENOXY‐ ACETATE ESTERS TO 2,4‐DICHLOROPHENOXYACETIC ACID IN SASKATCHEWAN SOILS
Authors: SMITH ALLAN E. 
Published: July 2006

Summary. The hydrolysis of the iso‐propyl, n‐butyl and iso‐octyl esters of 2,4‐dichloro‐phenoxyacetic acid to the free acid was studied in aqueous solutions and on three prairie soils. The esters were analysed using electron‐capture gas chromatography following extraction from solution with benzene, and from soils, using either 10% aqueous aceto‐nitrile or a 2:1 mixture of benzene and iso‐propanol.Ester hydrolysis in 0·1 n sodium hydroxide solution was very rapid, more than 50% of all the esters being hydrolysed in less than 1 min. In 0·1 n sodium carbonate solution the times for 50% hydrolysis at 25°C were < 5, 5 and 30 min for the n‐butyl, iso‐propyl and iso‐octyl esters respectively. In distilled water negligible hydrolysis occurred over a 5 h period.The iso‐propyl and n‐butyl esters underwent a very facile hydrolysis on soils. Shaking the treated soils with 0·1 M calcium chloride solution for 30 min at 25°C resulted in extensive hydrolysis to the acid as determined spectrophotometrically. Under similar conditions negligible hydrolysis of the iso‐octyl ester occurred.After 1·5 h at 25±1°C on soils at their wilting point moisture levels, and greater, less than 15% of the applied iso‐propyl or n‐butyl esters could be recovered using either extraction procedure, indicating rapid hydrolysis to the acid. After 24 h no iso‐propyl or n‐butyl ester residues could be detected in any of the soils. Loss of the iso‐octyl ester was slower under these conditions with approximately 20–30% of the ester remaining after 24 h, and 10% after 48 h. L'hydrolyse des esters de 2,4 dichlorophénoxyacétates en acide 2,4 dichlorophénoxyacétique dans les sols du saskatchewan.
THE USE OF A LOW DOSE OF ATRAZINE ALONE AND IN MIXTURES WITH OTHER HERBICIDES IN THE MAIZE CROP
Authors: LUDWIG J. W. 
Published: July 2006

Summary. Linuron, 2,4‐D‐aniine, propachlor, pyriclor and cypromid, singly and mixture with atrazine, were compared with atrazine and fluromidine alone for effectiveness of weed control in maize on Oxford clay soil. Pre‐emergence applications were made under wet conditions and atrazine, even at 0·28 kg/ha a.i. gave an excellent control of three main weeds, Stellaria media, Veronica spp. and Polygonum aviculare, and at 0·56 kg/ha also killed Aethusa cynapium. Fluromidine was comparable with atrazine, but linuron,2,4‐D‐amine, propachlor and pyriclor were less effective. Post‐emergence treatments were less satisfactory. High doses of atrazine were needed for good weed control. Acynapium was resistant to pyriclor and cypromid and P. aviculare to fluromidine. 2,4‐Daminewas ineffective, but atrazine/2,4‐D‐amine mixtures were more effective than the individual components for the control of P. aviculare. Pyriclor, at 0·56 kg/ha pre‐emergenceand cypromid at 2·24 kg/ha post‐emergence directly reduced the yield of the crop.Utilisation de I'atrazine à faible dose, seule et en mélange avec d'autres herbicides, dans les culturesde maïs
PHYSIOLOGICAL EFFECTS OF DALAPON IN CYNODON DACTYLON (L.) PERS.*
Authors: MARODER H. L. 
Published: July 2006

Summary. Studies on the physiological effects of dalapon in Cynodon dactylon (L.) Pers. were carried out. Field and glasshouse experiments showed that dalapon is freely translocated in the aerial organs and from these to the rhizomes. No transformation of the herbicide was detected during 72 h following application. In rhizomes as well as in stolons, dalapon caused growth inhibition and necrosis of buds while root growth was apparently not affected. This differential susceptibility was confirmed by culturing node explants in nutrient solution containing dalapon. Although dalapon killed aerial organs, most rhizomes were capable of recovery even when a high dose was applied. These results are discussed. Effets physiologiqius du dalapon sur Cynodon dactylon (L.) Pers.
THE PERSISTENCE AND PENETRATION OF LARGE DOSES OF SIMAZINE IN UNCROPPED SOIL
Authors: CLAY D. V. , STOTT K. G. 
Published: July 2006

Summary. The residues remaining in the soil from repeated annual application of simazine at 2–8, 5–6, and 22–4 kg/ha to uncropped plots on a loam soil were measured by chemical or bioassay methods at various intervals after treatment.The total simazine residue present 12 months after the last of three treatments with 2–8 kg/ha and 8 months after the last of five treatments with 5–6 kg/ha was less than 10% of the annual dose. This rapid decomposition is considered consistent with the soil and climatic conditions. In contrast a much larger residue (a mean value of 1·7 kg/ha) was found on plots sampled 21/2 years after the last of two annual applications of simazine at 22·4 kg/ha and the reduction in the amount of residue during the next 12 months was only of the order of 25%.In all treatments the highest concentration of simazine was found in the surface layers of the soil but measurable residues were detected to 60 cm depth, 31/2 years after the last 22·4 kg/ha application.There was considerable variation in the total residues recovered between replicate plots and between different positions on the same plots in all treatments regardless of the depth of the sample. The possible causes of this variation are discussed.Persistance et pénétration de fortes doses de simazine dans un sol non cultivé
THE ADSORPTIVE BEHAVIOUR OF ACID AND ESTER FORMS OF 2,4‐D ON SOILS
Authors: GROVER R. 
Published: July 2006

Summary. The adsorption of acid, n‐butyl, and iso‐octyl ester forms of 2,4‐D (2,4‐ dichloiophenoxyacetic acid) was studied for several Canadian prairie soils. The k values for the acid ranged from 0·09 to 1·30 and were correlated to the soil organic matter and not to the clay content. The Q, values (μg adsorbed/g of organic matter) for the acid were 7–2±l. The n‐butyl and the iso‐octyl esters hydrolysed to the acid form in the aqueous medium and this process was accelerated in the presence of the moist soil. Consequently, the k values for the esters, using slurry type adsorption experiments, or their distribution coefficients, using leaching columns, could not be determined. It was concluded that the adsorptive behavior of the two esters in moist soil was similar to that of the acid form.Comportement des formes actde, et ester du 2,4‐D quant à leur adsorption dans tes sols
TRANSLOCATION AND PERSISTENCE OF 2,4‐D IN POPULUS TREMULA L.
Authors: ELIASSON L. 
Published: July 2006

Summary. Treatment of aspen (Populus tremula L.) with 2,4‐dichlorophenoxyacetic acid (2,4‐D), using a leaf spray, basal bark spray or a stem injection method of application, resulted in some reduction of stump regrowth although downward translocation of 2,4‐D was slight. Persistence of 2,4‐D in dead leaf tissue and in woody tissue near the injection sites was observed. This persistence could in certain circumstances be noted 6 years after treatment. Migration et persistance du 2,4‐D chez Populus tremula L.
CONTROL OF REGENERATION IN ROOTS OF THE DEEP‐ROOTED WEED CHONDRILLA JUNCEA L.
Authors: CASO O. H. , KEFFORD† N. P. 
Published: July 2006

Summary. A system was developed for testing the ability of herbicides applied to the shoots of the deep‐rooted weed Chondrilla juncea to inhibit the regeneration of buds on serial sections along the root. Auxin herbicides known to inhibit regeneration when applied directly to root sections and with a potential for translocation or slow metabolic conversion to an active auxin were selected for testing. The most effective herbicides tested were picloram, N‐(diethylaminomethyl)‐2,4‐dichlorophenoxyacetamide and 2,4‐dichlorophenoxy‐acet‐O‐methylhydroxamic acid. Each compound reduced bud formation along 40 cm of root. The inhibition of regeneration by the sodium salt of 2,4‐D was decreased at temperatures above 25°C. The growth retardants chlormequat chloride, chlorphonium chloride and B‐995 were tested as inhibitors of regenerated‐bud growth and emergence when applied to shoots; only B‐955 was inhibitory. Amitrole and tris‐(laziridinyl) phosphine oxide inhibited bud formation and growth. Suppression de la régénération par les racines de Chondrilla juncea L., mauvaise herbe à encrainement profond.
DETOXIFICATION OF FLUOMETURON BY CITRUSTISSUES*
Authors: MENASHE J. , GOREN R. 
Published: July 2006

Summary. The metabolism of [14C]fluometuron in Citrus was studied by feeding the herbicide to either young seedlings or to excised organs. Most of the uptake of fluometuron occurred via the roots during the first 24 h and radioactivity was found after 16 days to be in the rootlets (36·5%), mainroot (34·5%), stem (13·7)% and leaves (15·2%). By feeding [14C]fluometuron to excised organs it was established that although most of the fluometuron breakdown occurred in the rootlets, other plant parts were also capable of metabolizing the herbicide. Therefore, the presence of metabolites in the upper plant organs was not entirely due to translocation from the rootlets. These results suggest that the resistance of Citrus to fluometuron is due to its breakdown in the tissues, probably induced by an N‐demethylase enzyme system, similar to that reported for cotton (Frear, Swanson & Tanaka, 1969), in which harmless metabolites arc formed. Détoxification du fluométuron par les tissus de Citrus
THE DISTRIBUTION OF AVENA FATUA L., AVENA STRIGOSA SCHREB. AND AGROPYRON REPENS (L.) BEAUV. IN BARLEY CROPS IN THE WEST OF SCOTLAND
Authors: WATERSON H. A. , DAVIES G. J. 
Published: July 2006

Summary. A survey of barley crops on 166 west of Scotland farms in 1969 indicated a more widespread distribution of Avena fatua L. than had previously been recognized. Whilst only 0·8% of the barley area was infested with A. fatua, the weed was found on 16% of the known barley‐growing farms. A. fatua was associated with arable farming situations and with fields where there was a recent history of cereal cropping. Only on four of the sample farms where A. fatua was found had any attempt been made to control the weed. It is concluded that there is a strong case for eradicating or at least containing the weed before it becomes a major problem.The distribution of Avena strigosa Schreb. and Agropyron repens (L.) Beauv. is also given. Distribution d'Avena fatua L., d'Avena. strigosa Schreb. et d'Agropyron repens (L.) Beauv. dans les cultures d'orge de l'ouest de l'Ecosse
SPATIAL GROWTH OF SORGHUM HALEPENSE (L.) PERS.*
Authors: HOROWITZ MENASHE 
Published: July 2006

Summary. Small plants of Sorghum halepense (L.) Pers. were planted in the field and grown without competition from weeds and crops for 2½ years. The plant spread by means of subterranean rhizomes from which aerial shoots developed at increasing distances from the plant centre, and by tillering around these aerial shoots to form clumps. No preferential direction of expansion was detected and established patches developed an approximately circular shape.Aerial growth stopped completely in the cold season. During the warm season the mean area increment amounted to 1·3 m2/month and was similar in both years of observations. After 2½ years of growth, patches had extended up to 3·4 m from the initial sprig and had a mean area of 17 m2.In the second summer of growth, shoot density reached 190/m2 and mean seed production was 84 g, or 28 000 seeds per plant.About 80% of rhizome dry weight was present in the upper 20 cm of soil and rhizomes did not penetrate deeper than 40 cm. About 80% of rhizome dry weight was present within 1 m radius from the plant centre. Croissance dans l'espace de Sorghum halepense (L.) Pers.
EFFECTS OF TEMPERATURE AND SOIL TYPE ON THE PHYTOTOXICITY OF TRIFLURALIN
Authors: RAHMAN A. 
Published: July 2006

Summary. Wheat, oats, and green foxtail were grown at day‐night temperatures of 32–16, 27–16, or 16–16°C in the growth chamber. The caryopses were planted at depths of 2·5 or 6·3 cm, and trifluralin was incorporated in the surface 5 cm of soil. The results indicated that the phytotoxicity of trifluralin was somewhat greater when plants were grown at day‐night temperatures of 32–16°C than at a temperature regime of 16–16°C. A further study in the greenhouse indicated that the phytotoxicity of trifluralin was dependant upon soil properties. In general, the toxicity of trifluralin to both wheat and green foxtail appeared to decrease with an increase in the organic matter content of the soil.Effets de la température et de la nature du sol sur la phytotoxicité de la trifluraline
SEED GERMINATION OF AGROSTIS GIGANTEA ROTH
Authors: WILLIAMS E. D. 
Published: July 2006

Summary. To assess the role of seed production and seedling behaviour in the biology of the perennial grass weed Agrostis gigantea Roth, seed germination and seedling emergence of the species were investigated in the glasshouse and in the laboratory. These studies showed that the species may produce a large number of seeds: panicles collected from a cereal field in 1971 and 1972 contained about a thousand viable seeds in both years. Mature seeds of the species are mostly non‐dormant and germinate readily on moist soil surfaces. Freshly‐harvested seeds require light and alternating tempratures for germination, but older seeds can germinate in constant temparature in the dark. Covering seeds with 0·6 cm soil halved the percentage emergence and few seedlings emerged from seeds sown deeper than 3±8 cm, but many seeds survived under enforced dormancy. A. gigantea seeds may also persist long in frequently cultivated shallow soil. The species flowers late but its seeds become viable quickly—in 1969 a third of the number that were finally viable became so within a week of flowering. Germination des semenes d' Agrostis gigantean Roth.