bluuebunny/crossref_metadata_2025 huggingface dataset:
HERBICIDE RESIDUE DETERMINATIONS AND TAINT TESTS ON FRUIT FROM GOOSEBERRIES TREATED WITH CHLORTHIAMID AND DICHLOBENIL
Authors: McKONE C. E. , HANCE R. J. , BURCHILL D. J.
Published: July 2006

Fruit harvested from gooseberry plots treated with up to 33·6 kg/ha of chlorthiamid and dichlobenil (applied at two dates) was examined for the presence of residues of 2,6‐dichlorobenzonitrile together with the possible metabolites, 2,6‐dichlorobenzamide and 2,6‐dichlorobenzoic acid. In addition the canned fruit was examined for taint. Residues of 2,6‐dichlorobenzonitrile resulting from the application of both herbicides at all rates were below 0·05 ppm. Residues of 2,6‐dichlorobenzamide ranged from 0·13 to 0·45 ppm with the greatest residues occurring in fruit from plots treated with the highest amounts of chlorthiamid in March. Fruit from some of the March applications of both herbicides contained residues of up to 0·16 ppm 2,6‐dichlorobenzoic acid. No taints were found in the canned fruit.
EFFECT OF ELECTROLYTES ON THE SOLUBILITY OF SOME 1,3,5‐TRIAZlNES AND SUBSTITUTED UREAS AND THEIR ADSORPTION ON SOIL*
Authors: HURLE KARL B. , FREED VIRGIL H.
Published: July 2006

Summary. The solubilities of three isopropylamino, ethylamino‐triazines (chloro‐, methoxy‐ and methylthio‐) and three, N′‐phenyl‐. NN‐dimethylureas (0, 1 and 2 chlorine substitutions on the phenyl group) were determined in water and in solutions of chloride salts of NH+4, K+ and Ca++ at ionic strengths of 0·3 and 0·6. Adsorption of these compounds by soil from the same chloride solutions at ionic strengths of 0·3 was measured. As expected, the solubilities were depressed by increasing ionic strength but the type of cation exerted a small, though significant, effect. Adsorption of the test compounds increased in the presence of the various salts. The possible import of these findings in relation to joint fertilizer and herbicide use and soil drying following herbicide application is commented on.

Effets des électrolytes sur la solubilité et l'adsorption par le sol de quelques 1,3,5‐triazines et urées substituées

Résumé. Les solubilités de trois isopropylamino, éthylamino‐triazines (Chloro‐, méthoxy‐et méthylthio‐), et de trois N′‐phényl‐NN‐diméthylurées (0, 1 et 2 chlores substitutés sur le groupe phényle) ont été déterminées dans l'eau et dans des solutions de sels de chlorure de NH4+, K+ et Ca++à des forces ioniques de 0,3 et 0,6. L'adsorption de ces composés par le sol à partir de ces mêmes solutions à la force ionique de 0,3 a été mesurée. Comme il était attendu, les solubilités furent diniinuées par l'accroissement de la force ionique mais la nature du cation exerça une influence faible mais néanmoins significative. L'adsorption des composés essayé fut accrue en présence des différents sels. La signification possible de ces réultats, en relation avec l'utilisation simultanée des engrais et des herbicides ainsi qu'avec le déssèchement du sol aprés um traitement herbicide fait l'objet de commentaires.

Einfluss von Elektrolyten auf die Löslichkeit einiger 1,3,5‐Triazine und Harnstoffderivate und auf ihre Adsorption an Boden

Zusammenfassung. Die Löslichkeit von drei Isopropylamino‐äthylamino‐triazinen (Chlor‐, Methoxy‐ und Methylthio‐) sowie drei N′‐Phenyl‐NN‐diniethyl‐harnstoffen (0, 1 und 2 Chlorsubstitutionen an der Phenylgruppe) wurden in Wasser und in Lösungen von NH4Cl, KCl und CaCl2 bei Ionenstärken von 0,3 und 0,6 bestimmt. Die Adsorption dieser Verbindungen an Boden aus Lösungen derselben Saize wurde bei der Ionenstarke von 0,3 gemessen. Wie erwartet wurde die Löslichkeit mit zunehmender Ionenstärke erniedrigt, wobei die Art des Rations einen kleinen, jedoch signifikanten Effekt zeigte. Die Adsorption der untersuchten Verbindungen nahm in Gegenwart der verschiedenen Salze zu. Es wird darauf hingewiesen, dass diese Befunde für die kombinierte Anwendung von Düngesalzen und Herbiziden wichtig sein können. Ebenso können sie wichtig sein für eine mögliche Austrocknung des Bodens nach Herbizideinsatz.
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 MCPA

Résumé. 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 Boden

Zusammenfassung. 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.
THE INFLUENCE OF THE METHOD OF APPLICATION OF PROMETON TO THE SOIL ON ITS TOXICITY TO WHITE MUSTARD (SINAPIS ALBA L.)
Authors: OSTROWSKI JANUSZ , HANCE R. J.
Published: July 2006

Summary. The effect of the method of incorporation of prometon into the soil on its phytotoxicity to white mustard was studied in pot experiments. Two groups of method were compared. In the first, the total quantity of soil to be used was mixed with the volume of appropriate prometon solution necessary to produce the required final herbicide and water concentrations. In the second group, the herbicide was initially mixed with a sub‐sample of soil which was then diluted with untreated soil to give the required final concentration.

Phytotoxicity was greatest when procedures of the second type were followed. There was no difference between the behaviour of wettable powder and unformulated applications.

Influence de la méthode d'application de la prométone dans le sol sur sa toxicité pour la moutarde blanche (Sinapis alba L.)
INTERACTIONS BETWEEN RESIDUAL HERBICIDES AT LOW CONCENTRATIONS*
Authors: HOROWITZ MENASHE , HERZLINGER GEZA
Published: July 2006

Summary. Immediate and residual phytotoxicity of binary combinations of several residual soil‐applied herbicides at 0·1 and 0·5 ppm was compared to the expected response calculated by Colby's formula. In one experiment diuron was combined with diphenamid, fluometuron, noruron, prometryne or simazine, and in another experiment trifluralin was combined with diuron or dichlobenil. The observed phytotoxicity of most combinations was only slightly different from the expected response. One combination, diuron 0·5 ppm + fluometuron 0·5 ppm, affected mustard significantly more than expected and this synergistic interaction remained appreciable after incubation of 2 months.

Interactions entre les herbicides persistants a faible concentration
TOLERANCE OF CRANBERRY (VACCINIUM MACROCARPON AIT) TO SAN‐9789: AN EXPERIMENTAL HERBICIDE
Authors: DEVLIN ROBERT M. , DEUBERT KARL H.
Published: July 2006

Summary. The experimental herbicide 4‐chloro‐5‐(methylamino)‐2‐(α,α,α‐trifluoro‐m‐tolyl)‐3(2H)‐pyridazmone (SAN‐9789) was applied to cranberry vines (Vaccinium macrocarpon Ait. cv. Early Black) in April at rates of 0, 9, 13·5, 18, and 27 kg a.i./ha. No phytotoxicity on vine growth or appearance was detected in plots receiving 9 kg/ha but at 13·5 kg/ha a temporary chlorosis at the base of the cranberry leaf blade was observed. More extensive and permanent chlorosis was caused by the larger application rates of 18 and 27 kg/ha. No significant differences were detected between control and treated berries with respect to colour, percentage dry weight, and size. However, application rates of 27 kg/ha significantly reduced pectin content of fresh cranberries. Berries from vines treated in April with SAN‐9789 did not contain detectable amounts of the herbicide at harvest time in September.

Résistance de la canneberge à gros fruits (Vaccinium macrocarpon Ait) à im herbicide expéri‐mental, le SAN‐9789
NN‐DIALLYL‐αα‐DICHLOROACETAMIDE AS AN ANTIDOTE FOR EPTC AND OTHER HERBICIDES IN CORN
Authors: CHANG F. Y. , BANDEEN J. D. , STEPHENSON G. R.
Published: July 2006

Summary. The efficacy of NN‐diallyl‐αα‐dichloroacetamide (R‐25788) as an antidote for reducing the injury of various herbicides in corn (Zea mays L.) was tested under controlled conditions in growth rooms. The application of R‐25788 to the soil as a pre‐plant incorporated treatment to corn significantly reduced the toxicity often out of twenty‐two herbicides tested. These ten herbicides were, in order of decreasing effectiveness of the antidote, EPTC, barban, sulfallate, vernolate, molinate, butylate, alachlor, pebulate, linuron and di‐allate. In quartz sand nutrient culture, R‐25788 was more effective as an antidote for barban applied to the foliage of corn than it was for barban applied to the roots.

Le NN‐diallyl‐αα‐dichloroacétamide comme antidote de I'EPTC et autres herbicides dans le mais.
A COMPARISON OF THE GROWTH AND COMPETITION BEHAVIOUR OF SEEDLINGS AND PLANTS FROM RHIZOMES OF AGROPYRON REPENS (L.) BEAUV. AND AGROSTIS GIGANTEA ROTH
Authors: WILLIAMS E. D.
Published: July 2006

Summary. Seedlings and plants derived from single‐node rhizome fragments of Agropyron repens and Agrostis gigantea were grown in au unheated glasshouse, separately or together with wheat (cv. Kolibri), in sandy loam soil in well‐spaced pots, adequately watered and moderately fertilized. Samples of crop and weeds were taken for growth analysis in mid‐ May, late June and early August (when the wheat was ripe).

On average, wheat decreased the weight of weed shoots by 84% and of rhizomes by 77%, but the weeds decreased the weight of wheat shoots by only 7% and of grain by 13%. Without wheat, seedlings of both weed species had, by late June, grown as much as plants from rhizomes, but with wheat, the weed seedlings were throughout most of the experiment more susceptible to competition than were plants from rhizomes. There was no simple relationship between the final dry weights of the weeds and the amount they decreased wheat yield: although Agropyron seedlings in competition with wheat were much lighter than Agrostis from rhizomes, they decreased grain yield of wheat as much, suggesting that they competed more intensely for a limiting factor, possibly nitrogen.

It is concluded that the faster initial growth rate of wheat seedlings relative to the weeds from rhizomes and a larger initial seed reserve relative to the weed seedlings enabled the wheat to dominate the weeds.

Comparaison de la croissance et comportement compétitif de plantules et de plantes issues de rhizomes d'Agropyron repens (L.) Beauv. et d' Agrostis gigantea Roth
AN AUTORADIOGRAPHIC STUDY OF THE DISTRIBUTION OF 14C LABELLED ASSIMILATES AT DIFFERENT STAGES OF DEVELOPMENT OF OXALIS LATIFOLIA H.B.K. AND O. PES‐CAPRAE L.
Authors: CHAWDHRY M. A. , SAGAR G. R.
Published: July 2006

Summary. An autoradiographic study of the distribution of 14C‐labelled assimilates, derived from 14CO2 fed to the aerial parts, was made at ten different developmental stages of Oxalis latifolia H.B.K. and Oxalis pes‐caprae L. Changing patterns of distribution of labelled assimilates to the underground parts of both species were revealed. These patterns are discussed in the context of the timing of control by defoliation and by foliageapplied herbicides.

Etude autoradiographique de la distribution des métabolites marqués an 14C à différents stades de développement de l'Oxalis latifolia H.B.K. et de l'O. pes‐caprae L.
Distribution et métabolisme du métha‐benzthiazuron chez des espèces végétales
Authors: COLLET G. F. , PONT V.
Published: July 2006

Summary: Résumé: Zusammenfassung

Le méthabenzthiazuron (MBT) migre rapidement des racines vcrs Ies feuilles, où il est plus ou moins activement métabolisé selon l'espéce végétale considérée. Les transformations métaboliques du MBT permettent d'isoler en particulier un catabolite (hydroxymethyle du MBT) relativement stable. Ce dernier est à l'origine d'une voie métabolique qui démé‐thyle peu à la chaine urée. D'autre part nous avons identié des produits de condensation avec le glucose. Quelques réactions métaboliques réversibles libêrent à nouveau du MBT à partir de certains de ses méatabolites.

Verteilung und Metabolismns von Metiiabenzihiazuron in empfindlichen odcr resistenten Pffanzenarten

MethahenzthiazuTon (MST wird scbnell von den zu den Blättem geleitet, wo es, abhängig von der jeweiligen Art, mehr oder weniger stark melabolisiert wird. Die Umwand‐lung von MBT ermöglicht insbesondere die Isolierung eines reiativ stabilen Abbauprodukts (Hydroxylmethyl‐MBT). Letzeres steht am Anfang eines Abbauwegs bei dem stufen‐weise die Hamstoifkette demethyliert wird. Ausserdem wurden einige Kondensationsprodukte mit Glucose identifi‐ziert. Verscliiedene reversible Stoffwechselreaktionen können auch MBT aus bestimmtcn Metaboliten freisetzen.

Distribution and metabolism of methabenzthiazuron in susceptible or resistant plant species

Methabenzthiazuron (MBT) passes rapidly from the roots towards the leaves where it is more or less actively metabolized depending upon the species considered. In particular, the metabolic transformations of MBT allow the isolation of a relatively stable catabolite (hydroxymethyl‐MBT). The latter is the origin of a metabolic pathway which gradually deme‐thylates the urea chain. Additionally, some products of condensation with glucose have been identified. Several reversible metabolic reactions can also release MBT from certain of its metabolites.
The time of the onset of competition between wild oats (Avena fatua L.) and spring cereal
Authors: CHANCELLOR R. J. , PETERS N. C. B.
Published: July 2006

Summary: Résumé: Zusammenfassung

Seven field experiments in spring wheat and barley with natural infestations ot A. fatua were set up to investigate the effects on grain yield of removing the weeds by hand at intervals during early growth stages. Only three sites showed any significant yield reductions and these all had populations of wild oats of 150 stems or more per m2 at harvest. No significant yield reductions occurred at lesser densities (20–100/m2). At the three higher‐density sites, competitive effects did not start until the crop had four leaves, about 4–5 weeks after it had emerged. A further experiment in a glasshouse designed to test if competition occurred prior to the emergence of crop and weed indicated no effect at all during this period.

Lépoque du déclenchement de la compétition entre la folle avoine (Avena fatua L.) et les céréales de printemps

Sept essais ensemencés en blé de printemps et en orge on t été implantés dans des champs présentant des infestations naturelles d'Avena fatua, en vue dévaluer les effets, sur le rendement en grain, de l'extirpation des mauvaises herbes à la main, à des intervalles réguliers durant les premiers stades de la croissance.

Trois essais seulement on t accusé des réductions significa‐tives des rendements et ceux‐ci avaient tous des populations de folle avoine de 150 pieds ou plus au m2 à la récolte. II n'y a pas eu de réductions significatives de rendement pour des densités inférieures (de 20 à 100/m2). Dans les trois essais à densitéélevée, les effets compétitifs ne commencérent pas avant que la plante cultivée ait atteint le stade 4 feuilles, 4 à 5 semaines environ aprés sa Ievée. Une expérience ulté‐rieure en serre réalisée pour rechercher si la compétition se produit avant la levée de la plante cultivée et de la mauvaise herbe n'a montré aucun effet durant cette pédode.

Der Zeitpunkt des Beginns einer Konkurrenz zwischen Flughafer (Avena fatua L.) und Sommergetreide

Es wurden sieben Feldversuche mit Sommerweizen und‐gerste mit einer natürlichen Verseuchung von A. fatua angelegt, um den Einfluss einer Beseitigung der Unkräuter von Hand zu verschiedenen Entwicklungsstadien auf den Kornertrag zu messen. Nur bei drei Versuchen waren ge‐sicherte Ertragsrückgänge festzustellen; die Flughaferdichte betrug in diesen Fällen zum Erntezeitpunkt 150 oder mehr Halme je m2. Bei geringeren Dichten (20–100/m2) waren keine gesichterten Ertragsminderungen feststellbar. In den drei Versuchen mit den höheren Dichten setzte die Konkurrenz nicht ein bevor das Getreide im 4‐Blattstadium war; das waren etwa 4–5 Wochen nach dem Aufiaufen. Es wurde ein weiterer Versuch im Gewächshaus angelegt, um festzustellen, ob die Konkurrenz vor dem Auflaufen des Ge‐treides und des Unkrauts eintrat. Während dieser Periode war kein Einfluss festzustellen.
Control of Datura stramonium L. with oxadiazon under simulated spray and furrow irrigation
Authors: FELTON W. L.
Published: July 2006

Summary: Résumé: Zusammenfassung

Cotton, soybeans and the weed species Datura stramonium L. were grown in the glasshouse under simulated spray and furrow irrigation. Oxadiazon at different rates was applied as a pre‐emergence treatment. The number of Datura, was decreased by higher rates of oxadiazon under spray irrigation but not with sub‐irrigation. Control at 4 kg/ha with spray irrigation was 75% but less than 15% with sub‐irrigation. Soybeans were less tolerant to oxadiazon than cotton but phytotoxicity was evident in both crops at 4 kg/ha.

La lutte contre le Datura stramonium L. avec l'oxadiazon sous irrigation simulée par aspersion ou par submersion.

Du coton, des sojas et une espèce de mauvaise herbe: Datura stramonium L., ont été cultivés en serre, sous irrigation simulée par aspersion ou par submersion. L'oxadiazon a été appliqué h différents taux en traitement de prévlevée. Le nombre de Datura a été diminué parles doses les plus élevées d'oxadiazon sous irrigation par aspersion mais pas par submersion. L'efBcacité herbicide à,4 kg/ha a été de 57% avec l'irrigation par aspersion mais moins de 15% avec l'irrigation par submersion. Les sojas se sont montrés moins résistants à l'oxadiazon que le coton, mais la phytotoxicitéétait évidente dans ces deux cultures à 4 kg/ha.

Die Bekämpfung von Datura stramonium L. mit Oxadiazon unter simulierter Beregnung und Furchenbewässerung

Baumwolle, Sojabohnen und das Unkraut Datura stramonium L. wurden unter simulierter Beregnung und Furchenbewasserung im Gewachshaus gezogen. Oxadiazon wurde mit verschiedenen Aufwandmengen im Vorauflauf angewendet. Bei hoheren Aufwandmengen ging die Anzahl von Datura bei Beregnung zuruck, nicht aber bei UntergrundbewSsser‐ung. Bei 4 kg/ha und Beregnung betrug die Bekampfung 75 %, bei UntergrundbewSsserung aber weniger als 15%. Die Sojabohnen waren gegenuber Oxadiazon weniger tolerant als Baumwolle, aber bei beiden Kulturpflanzen trat bei 4 kg/ha Phytotoxizitat auf.
Ecology and control of blackberry (Rubus fruticosus L. agg.)
Authors: AMOR R. L.
Published: July 2006

Summary: Résumé: Zusammenfassung

Cutting off the canes, either at ground level or at a height of IS cm, stimulated the formation of suckers from lateral roots of Rubus procerus P. J. Muell. The application of 2,4,5‐T or picloram sprayed on the foliage killed many plants, suppressed shoot production from the crowns of others, but stimulated sucker formation.

Within age groups of from 1 to 5 years, older plants were more resistant to 2,4,5‐T (0067%, 020%) and to picloram (0067%) than were younger plants. Picloram (020%) was the most effective treatment and affected plants of all ages equally.

it is suggested that the age of plants may be a major source of variation in the efficacy of herbicides on other perennial weeds.

Ecologie des ronces (Rubus fruticosus L. agg.) et méthodes de lutte. III‐Réaction de R. procerus au fauchage et aux applications d'herbicides sur le feuillage

Le fauchage des tiges, aussi bien au niveau du sol qu'a une hauteur de 15 cm, a stimuli la formation de drageons k partir des racines laterales de Rubus procerus P. J. Muell. L'application de 2,4,5‐T ou de piclorame en pulvérisation sur le feuillage a tué beaucoup de plantes, a supprimé chez d'autres la production des pousses à partir des couronnes, mais a stimulé la formation de drageons.

Parmi les groupes d'àge de un à cinq ans, les plantes les plus agés ont été plus riisistantes que les plus jeunes au 2,4,5‐T (0,067%, 0,20%) et au piclorame (0,067%). Le piclorame (0,20%) a été le traitement le plus efficace et a affiectéégalement des plantes de tous âges.

II est suggéré que l'âge des plantes peut étre une importante source de variation dans l'efficaclté des herbicides sur d'autres plantes pérennes.

Ökologie und Bekämpfung der Brombeere (Rubus fruticosus L. agg.) 111. Reaktion von Rubus procerus auf meehanische Entfernung oberirdisclier Pfianienteile und auf blartapplizierte Merbizide

Das Abschneiden der Ruten—entweder an der Bodenober‐filiche Oder in 15 cm Höhe—fordert bei Rnbus procerus P. J. Muell. die Ausbildung von Wurzelsprossen aus Seitenwurt zeln. Die Blattbehandlung mit 2.4,5‐T oder Picloram toter viele Pflanzen ab und unterdrilckt die Sprossbildung de‐Seitentriebe, fordert aber die Wurzelsprossbildung. Inner‐halb der Ahersgruppen von 1–5 Jahren sind Sltere Ptlanzen widerstandsfahiger gegenuber 2,4.5‐T (0.067%, 0.20%) und Picloram (0.067%) als jungcre Pflanzen. Picloram (0,20%) zeigte die beste Wirkung und erfasste die Pflanzen in alien Altersstufen gleich. Es wird vermutet, dass das Alter von Pflanzen die Hauplurscahe unterschiedlicher Wirksamkeit von Herbiziden auch bei anderen mehrjflhrigen Unkrflutern ist.
Preliminary field trials with 2,4‐D ester, barban and tri‐allate applied in spray volumes of 5–20 l/ha
Authors: TAYLOR W. A. , MERRITT C. R.
Published: July 2006

Summary: Résumé: Zusammenfassung

A machine is described for experimental application of herbicides in volumes of spray liquid in the range 5–20 I/ha and at a uniform drop size. Uniformity of distribution is comparable to that from a conventional small‐plot sprayer working under optimal conditions. The machine was used to apply 2,4‐D ester, barban and tri‐allate. Subsequent biological assessments revealed no major loss of effectiveness in weed control when compared with applications in 165 or 200 I/ha sprayed through hydraulic fan nozzles as in contemporary field practice.

Essais préliminaires au champ avec l'ester du 2,4‐D, le barbane et le triallate appliqués en pulvérisation avec un volume de 5 à 20 l/ha

Un appareil est décrit pour l'application expérimental d'herbicides en pulvérisation avec un volume de liquide alla de 5 à 20 I/ha et une taille uniforme de gouttes. L'uniformité de la distribution est comparable à celle d'un pulvérisateur pour petites parcelles travaillant dans des conditions optimales. L'appareil a été utilisé pour appliquer du 2.4‐D ester, du barbane et du triallate. Des essais biologiques effectués & la suite des traitements ont montré qu'il n'y avait pas de perte importante d'efficacité herbicide par comparaison avec des traitements appliqués avec 165 ou 200 1/ha en utilisant les buses S fente en usage dans la pratique actuelle des traitements au champ.

Vorläufige Feldversuche mit 2,4‐D Ester, Barban und Triallat mit Brühemengen von 5–20 l/ha

Es wird ein GerSt beschrieben mit dem versuchsmässig Herbizide mit Brühemengen zwischen 5 und 20 1/ha bei gleichbleibender Tropfengrösse ausgebracht werden können. Die Gleichmässigkeit der Verteilung lässt sich mit der eines unter optimalen Bedingungen arbeitenden Parzellenspritz‐geräts vergleichen. Mit diesem Gerät wurden 2,4‐D Ester, Barban und Triallat ausgebracht. Die darauffotgende bio‐logische Früfung zeigte keinen wesentlichen Verlust in der Wirksamkeit der Unkrautbekämpfung, verglichen mit den gegenwärtig üblichen Verfahren mit 163 oder 200 l/ha und Flachstrahldüsen.