bluuebunny/crossref_metadata_2025 huggingface dataset:
ZUR SELEKTIVITAT VON PHENMEDIPHAM ALS NACHAUFLAUFHERBIZID IN BETA‐RÜBEN*
Authors: ARNDT F. , KÖTTER C.
Published: July 2006

Summary. Sugar beet are outstandingly tolerant to 3–methoxycarbonyIaminophenyl‐A′‐(3′‐methylphenyl) carbamate phenmedipham) and the difference in susceptibility between the main weeds prevalent in beet crops and the beet themselves can be used to obtain selective weed control. The herbicide is applied post‐emergence; action via the soil can be excluded as non‐existent.

A test with twenty‐nine varieties of sugar beet and one variety of fodder beet showed no interaction between phytotoxicity and variety. No variety particularly susceptible to phenmedipham was found.

Investigations on the mode of action and selectivity proved that phenmedipham is a strong inhibitor of the Hill reaction. There were no differences in the extent of inhibition of the Hill reaction in chloroplasts of a sensitive plant (mustard) as compared with a resistant species (sugar beet). Measurements of photosynthesis using infra‐red absorption methods and intact plants showed that it was inhibited in both sensitive and resistant species: the degree of inhibition, however, varied according to the species. In contrast to susceptible weeds, the resistant sugar beet and Amarantus relroflexus showed recovery in assimilation, and the recovery phases were significant. It can thus be concluded that sugar beet and A. retroftexus are able to inactivate phenmedipham.

Sélectivité du phenmediphame, herbicide de post‐levée dans les cultures de de betteraves sucrièes
3,4,3′,4′‐RACHLOROAZOBENZENE: ITS TRANS‐LOCATION AND METABOLISM IN RICE PLANTS
Authors: STILL GERALD G.
Published: July 2006

Summary. 3,4,3′,4′‐Tetrachloroazobenzene (TCAB) and TCAB‐14C were supplied to the roots of rice (Oryza sativa L.) plants in nutrient solution. An analysis of the shoots indicated that the TCAB was absorbed and translocated to the shoots. The translocated material was characterized by gas‐liquid chromatography and mass spectrometry. Roots were exposed to saturation concentrations of TCAB‐14C in liquid culture to determine the translocation and distribution of the compound. Only 5′6% of the total azobenzene present in the nutrient solution was absorbed by the intact rice plants and only 3′2% of the absorbed TCAB‐14C was translocated to the shoots after 12 days of treatment. No TGAB was isolated from plants treated with propanil or 3,4‐dichloroaniline after 14 days of treatment.
UPTAKE OF COPPER IN HYDRILLA*
Authors: SUTTON DAVID L. , BLACKBURN R. D.
Published: July 2006

Summary. A linear increase from 933 to 15,943 ppmw of copper occurred in hydrilla (Hydrilla verticillata Casp.) 4 days after treatment with copper sulphate pentahydrate (CUSO4. 5H2O, CSP) at 0·5–4·0 ppmw of copper. Neither increase in calcium levels to 0·8 MM in the ambient solution nor aeration affected the amount of copper in excised hydrilla tissue during a 24‐h treatment period with CSP at 1·0 ppmw of copper. Part of the accumulated copper appeared to be bound in hydrilla. A higher accumulation of copper occurred after treatment with an organic copper complex (cutrine) than with either CSP or copper chloride (CuCI2.2H2O, at 1·0 ppmw of copper. This high accumulation with cutrine appeared to be related principally to the amount of copper remaining in the treatment solution.
PLANT GROWTH STIMULATION BY SUBLETHAL CONCENTRATIONS OF HERBICIDES*
Authors: WIEDMAN STEVEN J. , APPLEBY ARNOLD P.
Published: July 2006

Summary. Significant stimulation of root or shoot growth of oats (Avena sativa L.) resulted from pre‐emergence applications of eleven herbicides at sublethal doses. Two additional herbicides stimulated cucumber (Cucumis sativus L.) root growth. Several types of herbicides with different mechanisms of lethal action were represented. Three herbicides failed to stimulate plant growth significantly in these studies, although all of them have been observed to cause growth stimulation in other experiments. Studies on oat seedling respiration, photosynthesis, protein content, free amino acid content, and total available soluble carbohydrates failed to provide any consistent explanation for stimulation. These results provide further evidence of the validity of the Arndt‐Schulz hypothesis which states that all poisons are stimulatory at sublethal concentrations.

Stimulation de la croissance des plantes par des concentrations sublétales d'herbiddes

Résumé. Une stimulation significative de la croissance des racines ou des tiges de I'avoine (Avena sativa L.) a été provoquée par l'application en pré‐levée de onze herbicides à des doses sublétaies. Deux autres herbicides ont stimulé la croissance des racines de concombre. Plusieurs types d'herbicides possédant des mécanismes diffrénts d'action létale étaient représentés. Trois herbicides n'ont pas provoqué de stimulation significative de la croissance au cours de cette étude, bien qu'ils aient provoqué une stimulation dans d'autres expériences. Des recherches sur la respiration, la photosynthése, la teneur en protéines, en amino‐acides libres et le total disponible des hydrates de carbone solubles dans la plantule d'avoine n'ont fourni aucune explication logique de la stimulation. Ces résultats apportent une nouvelle preuve de la validité de l'hypothése d'Arndt‐Schulz selon laquelle tous les poisons ont un effet stimulant à des concentrations sublétaies.

Förderung des Pflanzenwachstums durch Herbizide in sublethalen Konzentrationen

Zusammenfassung. Die Vorauflaufanwendung von elf Herbiziden in sublethalen Dosen förderte das Wurzel‐ und Sprosswachstum von Hafer (Avena sativa L.) signifikant. Zwei weitere Herbizide stimulierten das Wurzelwachstum bei der Gurke (Cucumis sativus L.). Es waren Herbizide aus verschiedenen Gruppen mit unterschiedlichem Mechanismus der lethalen Wirkung vertreten. Drei Herbizide förderten in diesen Studien das Wachstum nicht signifikant, obwohl eine solche fördernde Wirkung in anderen Experimenten beobachtet worden war. Untersuchungen der Atmung von Haferkeimlingen, der Photosynthese, des Proteingehaltes, des Gehaltes an freien Aminosäuren und der Gesamtmenge an löslichen Kohlenhydraten erbrachten keine einheitliche Erklärung für die Förderung. Diese Ergebnisse stützen die Gültigkeit der Arndt‐Schulz Hypothese, die besagt, dass alle Gifte in sublethalen Dosen stimulierend wirken.
SPATIAL GROWTH OF CYNODON DACTYLON (L.) PERS.*
Authors: HOROWITZ MENASHE
Published: July 2006

Summary. Small sprigs of Cynodon dactylon (L.) Pers., were planted and grown without competition from weeds and crops for 2 1/2 years. The plant spread by means of above‐ground creeping stolons and subterranean rhizomes which could also emerge as aerial shoots, producing in their turn new stolons and rhizomes. Initially there was linear extension of stolons and rhizomes, following which gaps in the sod were filled by stolon branching and new shoots. There was no preferential direction of stolon elongation and established sods developed an approximately circular shape and expanded concentrically. The rate of increase in sod area was similar in both years of observation but radial extension was smaller in the second year than in young plants.

The mean sod area was 25 m2 after 2½ years of growth, and mean monthly area increment was 0·9 m2. Growth almost stopped in the cold season and exceeded 2 m2 per month in the summer. The plants had extended up to 3·9 m from the plant centre after 2 1/2 years. The number of flowering culms per sod, produced only in the warm season, was directly proportional to sod area; seeds were infertile in the Newe Ya'ar area.

After 2½ years of growth about 70% of the rhizome dry weight was present in the upper 20 cm of soil. Few rhizomes penetrated deeper than 40 cm. More than 60% of the rhizomes were present within 1 m radius of the plant centre and 90% were present within 2 m radius.

Croissance spatiale de Cynodon dactylon (L.) Pers.
SOME PHYSICO‐CHEMICAL INTERACTIONS OF PARAQUAT WITH SOIL ORGANIC MATERIALS AND MODEL COMPOUNDS I. EFFECTS OF TEMPERATURE, TIME AND ADSORBATE DEGRADATION ON ARAQUAT ADSORPTION
Authors: BURNS I. G. , HAYES M. H. B. , STAGEY M.
Published: July 2006

Summary. Some investigations were carried out on the adsorption of paraquat by a range of organic materials which included an organic soil, various humic fractions from that soil, model polymers prepared by the oxidative coupling of benzoquinone, the ion exchange resins Zeo‐Karb 216 and 226, and Amberlite XAD‐2. The time required for the adsorption process to reach equilibrium ranged from about 3 h (for the soil and humic preparations) to about 48 h (for the more highly cross‐linked materials). Adsorption by Amberlite XAD‐2, a cross‐linked polystyrene resin, was very small, presumably because it lacked ion‐exchange sites.

The results suggested that particle diffusion control was operating and the different equilibrium times reflected different degrees of molecular complexity within the adsorbents.

Temperature, within the 20°–70°C range, did not affect the adsorption equilibrium, and this is indirect evidence for ion exchange as the primary adsorption mechanism. No evidence was found for decomposition of paraquat in the adsorption systems studied.

Quelques interactions physico‐chimiques du paraquat avec des inatéaux de sol organique et des composes modéles I. Effets de la température, du temps et de la dégradation sur I'adsorption du paraquat
THE SELECTIVE ACTION OF PICLORAM IN RED MAPLE AND WHITE ASH
Authors: MITCHELL B. J. F. , STEPHENSON G. R.
Published: July 2006

Summary. White ash (Fraxinus americana L.) trees, 2 years of age, treated continuously with 10 ppm picloram (4‐amino‐3,5,6‐trichloropicolinic acid) in nutrient culture were only slightly injured after 4 weeks whereas red maple (Acer rubrum L.) trees were killed after only 2 weeks treatment.

When the roots were exposed to 10 ppm 14C‐picloram, the rate of root uptake, acropetal translocation in the stem, and accumulation in the leaves was much lower in the susceptible red maple than in the tolerant white ash. The foliar penetration and translocation of 14C‐picloram applied to the leaves was very slight but similar in both species. Although a radiolabelled picloram metabolite was isolated from plant extracts, it was formed at equal rates in both species.

It was concluded that the tolerance of white ash was not related to lower rates of picloram uptake or faster rates of picloram detoxication. It was postulated that the high susceptibility of red maple was due to a blockage of the xylem by picloram which caused death by a dessication of the leaves and upper stems.

Action sélective du piclorame sur Fraxinus amerieana L. et Acer rubrum L.
RESPONSE OF A PASTURE TO REMOVAL OF DOCKS (RUMEX SPP.) BY TREATMENT WITH ASULAM
Authors: SAVORY B. M. , SOPER D.
Published: July 2006

Summary. Asulam at 1 lb/acre was sprayed on forty‐two plots in a dock‐infested ryegrass/timothy sward in May, 1970. Each plot was paired with an untreated plot, containing nearly the same ground cover of docks. The plots were selected to represent the whole range of dock cover existing on the site (3–54%). Harvest cuts of dorks and grasses separately were taken one week post‐treatment, and twice subsequently in 1970 and twice in 1971. The percentage change in grass and total herbage yield ratios was plotted against initial dock cover for each pair of plots at each harvest and subjected to regression analysis.

Significant correlations were obtained between grass yield ratios and initial dock cover for harvest 2, 3 and 2–5 combined: those plots which initially contained the largest dock populations gave the largest increases in grass yields after asulam treatment. Total herbage yield ratios were not correlated with initial dock cover at any harvest.

Overall, total herbage yields for the 2 years were not altered by asulam treatment, but grass formed 98·3% of the total yield on the treated plots, compared with 87·5% on the untreated. Asulam gave complete control of docks in 1970 and 73% on a dry weight basis in September, 1971.

Reaction d'une pâture traitée avec l'asulam contre les rumex (Rumex spp.)
DIE AUFNAHME VON ADSORBIERTEM MONOLINURON IM BODEN DURCH SENFPFLANZEN
Authors: SÜSS A. , GRAMPP B.
Published: July 2006

Zusammenfassung. Um den Einfluß verschiedener Bodenmischungen auf die Aufnahme von adsorbiertem [14C]‐markíertem Monolinuron zu verfolgen, wurden jeweils 30, 45, 60, 73 und 90 g Monolinuron‐behandelter Boden (0,42‐0,53 μg Monolinuron/g Boden) mit unbehandeltem auf 100 g aufgefüllt und damit 15.4–67.1 μg adsorbiertes Monolinuron eingesetzt. Die Aufnahme durch Senipflanzen wurde in Neubauerversuchen während 24 Tagen verfolgt. In 3 Anbauperioden wurden 1.17–9.74 μg aufgenommen. Der überwiegende Teil blieb jedoch an den Boden adsorbiert. Bei einer Bilanzerstellung konnten 99% der zu Versuchsbeginn eingesetzten Monolinuronmenge wieder gefunden werden, Durch den Sorptionsprozeß wurde Monolinuron chemisch nicht vcerändert. Ebenso kann das Ausgangsmolekül in der Pflanze nachgewiesen werden. Die nachweisbare Monolinuronmenge in der Pflanzensubstariz wird umso geringer, je weiter die Aufnahmeintensität zurürkgeht. Über eine Isotopen‐Austauschreaktion wurde versucht, das pflanzenverfügbare Monolinuron zu messen.

The uptake of adsorbed monolinuron in the soil by mustard plants
CHEMICAL WEED CONTROL IN BROADCAST‐SEEDED FLOODED TROPICAL RICE
Authors: DE DATTA S. K. , BERNASOR P. C.
Published: July 2006

Summary. Several new herbicides were tested for control of weeds in broadcast‐seeded flooded tropical rice. Among the new herbicides, S‐(2‐methyl‐l‐piperidylcarbonyl‐methyl)‐O,O‐di‐n‐propyl dithiophosphate (C‐19490), S‐(2‐methyl‐l‐piperidylcarbonyl‐methyl)‐O,O‐di‐n‐propyl dithiophosphate combined with 2‐(1′,2′‐dimethylpropylamino)‐4‐ethylamino‐6‐methylmercapto‐s‐triazine [C‐19490/C‐18898 (C‐288)], and N‐secondary‐butyl‐4‐tertiary‐butyl‐2,6‐dinitroaniline (A‐820) were highly selective in controlling Echinochloa crus‐galli (barnyard grass) and other annual weeds under tropical conditions. S‐(4‐chlorobenzyl)‐N,N‐diethylthiol carbamate (benthiocarb) and N‐(butoxymethyl)‐2‐chloro‐2′,6′‐diethylacetanilide (butachlor) continued to look promising in our experiments. Only butachlor is widely used in Asia.

Désherbage chimique des cultures tropicales de riz inorndé, seméà la volée
Effect of the form of a deposit on the activity of barban applied to Avena fatua L.
Authors: LAKE J. R. , TAYLOR W. A.
Published: July 2006

Summary: Résumé: Zusammenfassung

Experiments are described where different forms of deposit of barban were applied lo wild oats (Avena fatua L.) by varying drop size (110. 220 or 440 μm diameter) and application rate. Plants were grown in trays in a glasshouse and sprayed in the laboratory using a spinning disc in a cabinet. The results showed that the form of a deposit can have a significant effect on herbicidal activity, deposits produced with the smallest drop size being the most effective.

Effect de la forme du depot sur l'activite du barbane appliqué sur Avena fatua (L.)

Des expériences sont décrites au cours desquelles différentes formes de dépöts de barbane ont ete appliquées sur de la folle avoine (Avena fatua L.) en faisant varier la taille des gouttes (110, 220 ou 440 μ de diamétre) et la dose d'application. Les plantes ont été cultivées sur tablettes en serre et traitées au laboratoire en utilisant un disque tournant dans une enceinte. Les résultats obtenus ont montré que la forme du dépót pouvait avoir un effet significatif sur I'activité de I'herbicide, les dépôts formes par les gouttes les plus petites étant les plus efficaces.

Einfluss der Art des Spritzbelages auf die Wirksamkeit von Barban gegenüber Avena fatua L.

Es werden Versuche über die unterschiedliche Applikation von Barban auf Flughafer (Avena fatua L.) beschrieben. Variiert wurden die Tröpfchengrösse (110, 220 oder 440 μm Durchmesser) und die Aufwandmenge. Die Pflanzen wurden im Gewflchshausangezogen und mit einem ZentrifugalzcrstSuber behandelt. Die Ergebnisse zeigen, dass die Art der Applikation einen gesicherten Einfluss auf die herbizide Wirkung haben kann, wobei die Applikation mit der kleinstcn Tröpfchengrösse am wirkungsvollsten war.
The residual activity of metribuzin in soil
Authors: LAY M. M. , ILNICKI R. D.
Published: July 2006

Summary: Résumé: Zusammenfassung

The residual activity of 4‐ammo‐6‐tert‐butyl‐3‐(methylthio)‐1,2,4‐triazine‐5‐4(H)one (metribuzin) on indicator plants in Sassafras sandy loam soil was studied. Inhibition of coleoptile. radicle and primary root development were found at 1 ppm in oat (Avena sativa L., var. Beede) and at 5 ppm in cucumber (Cucumis sativus L., var. Pepino). At concentrations below 5 ppm, metribuzin stimulated the elongation of primary root and radicle in cucumber. After 46 days’ incubation. less than 1 ppm of the intact compound remained in soil without affecting the elongation of oat roots while its half life was approximately 6 days at 28deg;C incubation.

L'activité résiduelle de la métribuzine dans le sol

L'activité résiduelle de la 4‐amino‐6‐t‐butyl‐3‐(méthylthio)‐1,2,4‐tHazine‐S‐(4H)‐one (métribuzine) a étéétudiée sur des plantes tests dans un sol sablo‐limoneux de Sassafras. L'inhibition de la coléoptile, de la radicule et du développement de la racine primaire a été constatéà la dose de 1 ppm pour l'avoine (Avena sativa L. var. Beede) et à 5 ppm pour le concombre (Cucumis sativus L. var. Peplno). A des concentrations inférieures à 5 ppm, la métribuzine a stimulé l'élongation de la racine primaire et de la radicule du concomposé. Après 46 jours d'incubation, moins d'un ppm du composé intact restait dans le sol sans affecter l'élongation des racines d'avoine, alors que sa demi‐vie a été approximativement de 6 jours à une température d'incubation de 28°C.

Die Residualwirkung von Metribuzin im Boden

Es wurde die Rcsidualwirkung von 4‐Amino‐6‐tert,‐butyl‐3‐(methylthio)‐1,2,4‐triazin‐5‐(4H)‐one (Metribuzin) an Indikalorpflanzen in Sassafras‐sandigem‐Lehm untersucht. Bei 1 ppm war bei Hafer (Avena sativa L., Sorte Beede) die Entwicklung der Koleoptile, der Keim‐ und der Primär‐wurzel gehemmt und bei 5 ppm desglcichen bei Gurke (Cucumis sativus L., Sorte Pepino). Bei Konzentrationen unter 5 ppm, förderte Metribuzin bei der Gurke die Streckung der Primär‐ und der Keimwurzel. Nach 46 Tagen Inkubation‐szeit war weniger als 1 ppm der unveränderten Verbindung im Boden, was aber das Längenwachstum der Haferwurzeln nicht beeinträchtigte. Die Halbwertzeit betrug bei 28°C ungefahr 6 Tage.
Measured and computed concentration patterns of propyzamide in field soils
Authors: Leistra M. , Smelt J. H. , Verlaat J. G. , ZANDVOORT R.
Published: July 2006

The persistence of propyzamide in soil was studied by analysing soil samples taken at intervals two or three times after application in the spring to experimental fields. Single samples were taken from other fields. 8 to 12 months after autumn application. The concentrations were measured by electron‐capture gas chromatography. Persistence is expressed in first‐order dissipation rate constants and half‐life values.

Data were measured and collected on the adsorption of propyzamide on soils, the soil characteristics and the weather conditions. Computations of the mobility of propyzamide in soil were carried out for simplified systems. Results of measurements and computations are compared.
Control of Cyperus rotundus with glyphosate: the influence of ammonium sulphate and other additives
Authors: SUWUNNAMEK U. , PARKER C.
Published: July 2006

Summary: Résumé: Zusammenfassung

Glyphosate was applied to Cyperus rotundus L. in combination with a range of other herbicides and certain non‐herbicidal additives. Most herbicides tended to have an antagonistic effect with glyphosate, especially those which inhibit photosynthesis. On the other hand 2,4‐D amine and aminotriazole showed at least additive and sometimes synergistic effects. Striking activation was obtained with ammonium sulphate added at rates between 1·25 and 10 kg/ha. Other compounds causing almost equal activation were several ammonium phosphates, ammonium butyl‐phosphate and urea. The activity of glyphosate on C. rotundus was considerably greater when applied 3 weeks after planting than at 9 weeks. The activation was also greater at 3 weeks but was still apparent at 9 weeks.

Lutte contre le Cyperus rotundus avec el glyphosate: influence du sulfate d’ammonium et d'autres adjuvants

Le glyphosate a été appliqué au Cyperus rotundus L. en association avec une série d'autres herbicides et certains adjuvants non‐herbicides. La plupart des herbicides manifestèrent un effet antagoniste avec le glyphosate, particulièrement ceux qui inhibent la photosynthèse. D'autre part, le 2,4‐D sel d'amine et l'aminotriazole montrérent des effets au moins additifs et quelquefois synergiques. Une activation frappante fut obtenue avec le sulfate d'ammonium ajoutéà des doses comprises entre 1,25 et 10 kg/ha. D'autres produits ont provoqué une activation à peu près équivalente: plusieurs phosphates d'ammonium, le butylphosphate d'ammonium et l'urée. L'efficacité du glyphosate sur C. rotundus a été considérablement plus élevée lorsqu'il a été appliqué 3 semaines après plantation, au lieu de 9 semaines. L'activation fut aussi plus grande à 3 semaines, mais était encore apparente à 9 semaines.

Bekämpfung von Cyperus rotundus mit Glyphosate: Der Einfluss von Ammoniumsulfat und anderen Zusätzen

Cyperus rotundus L. wurde mit Glyphosate in Kombination mit einer Reihe anderer Herbizide und bestimmter nicht‐herbizider Zusätze behandelt. Die meisten Herbizide zeigten mit Glyphosate die Tendenz einer antagonistischen Wirkung, insbesondere solche, die die Photosynthese hemmen. Andererseits wirkten 2,4‐D‐Amin und Aminotriazol zumindest additiv und manchmal auch synergistisch. Eine beeindruckende Aktivierung wurde mit Ammoniumsulfat bei Aufwandmengen zwischen 1·25 und 10 kg/ha erreicht. Andere Verbindungen, die eine fast gleichwertige Aktivierung bewirkten, waren verschiedene Ammoniumphosphate, Ammoniumbutylphosphat und Harnstoff. Die Aktivität von Glyphosate war beträchtlich höher, wenn es 3 Wochen, statt 9 Wochen nach dem Pflanzen angewendet wurde. Die Steigerung war zwar nach 3 Wochen grösser, war aber auch noch nach 9 Wochen festzustellen.
Effect of soil storage on propanil degradation
Authors: LAY M.M. , ILNICKI RICHARD D.
Published: July 2006

Summary: Résumé: Zusammenfassung

Sassafras sandy loam soil was subjected to various storage conditions after collection and 3′,4′‐dichloropropionanilide (propanil) was used for testing the biodegradation potential of the stored soil. Cleavage of propanil was affected drastically after 5 days’ moist storage at 0, 10, 25 or –15° C and by 5 days’ air‐drying. In 1 week approximately 90% of the propanil was degraded when fresh soil samples were used. However, 60–80% of residual propanil was found in soil which had been stored under various conditions from 5 to 30 days. Samples air‐dried for 10 days were mildly affected as compared with the samples moist‐stored at various temperatures, indicating that restricted gas exchange had a detrimental effect on biodegradation in moist‐stored samples. These findings show that any biodegradation study should be conducted with fresh soil samples.

Effet de la conservation du sol sur la degradation du propanil

Un sol argilo sableux a été soumis apres prélèvement à diverses conditions de conservation et du 3,4‐dichloropro‐pionanilide (propanil) a été utilisé pour estimer le potentiel de biodégradation du sol ainsi conservé. La dégradation du propanil aété profondément affectée aprés 5 jours de conservation à l'humidité, à 0, 10, 25 ou –15° C et par 5 jours de séchage à l'air. En une semaine, 90 % environ du propanil aété dégrade dans le cas oil des échantillons frais de sol ontété utilises. Toutefois, 60 a 80 % de propanil résiduel aété retrouvé dans un sol conservé pendant 5 à 30 jours dans des conditions variées. Les eéchantillons séchés k l'air pendant 10 jours ontété moyennement affectés en compar‐aison avec les échantillons conserves ä l'humiditéä des températures variées; ceci indique que la restriction des échanges gazeux a un effet défavorable sur la biodégradation dans les échantillons conserves à rhumidité. Ces résultats montrent que toute étude de biodégradation devrait être conduite avec des échantillons de sol frais.

Wirkung der Lagerung von Boden auf den Abbau von Propanil

Boden (Sassafras‐sandiger‐Lehm) wurde nach der Probennahme unter verschiedenen Bedingungen gelagert und, seine biologische Abbaufahigkeit mit 3′,4′‐Dichlorpro‐pionanilid (Propanil) untersucht. Der Abbau von Propanil wurde nach fünftägiger Lagerung des Bodens in feuchtem Zustand bei 0, 10, 25 oder – 25°C und fünftägiger Lufttrocknung sehr stark beeinflusst. Wenn frische Bodenproben verwendet wurden, waren nach einer Woche etwa 90% des Herbizids abgebaut. Dagegen waren noch 60–80% des Propanils vorhanden, wenn der Boden unter verschiedenen Bedingungen 5–30 Tage gelagert worden war. Proben die 10 Tage lang luftgetrocknet wurden, waren, verglichen mit den bei verschiedenen Temperaturen feucht gelagerten Bodenproben, nur wenig beeinflusst. Das weist darauf hin, da ein verringerter Gasaustausch sich schädlich auf die im feuchten Zustand gelagerten Proben auswirkte. Diese Ergebnisse zeigen, dass jede Untersuchung des biologischen Abbaus von Herbiziden im Boden mit frischen Bodenproben durchgefuhrt werden sollte.
Persistence and mobility of bromacil in orchard soils
Authors: LEISTRA M. , SMELT J. H. , ZANDVOORT R.
Published: July 2006

Summary: Résumé: Zusammenfassung

Bromacil was applied annually for 6 or 7 years in two apple‐orchard experiments. At intervals of a year after the last applications, concentrations at various depths down to more than 1 m were measured by gas‐liquid chromatography. On an average, 54% of the annual dosage was still present, corresponding to a decline to 35% of the initial amount within a year. The highest concentration in the profile was found at about 10–20 cm, which indicates a much lower mobility than that found with soil thin‐layer experiments. Traces of bromacil were found at depths around 1 m, especially with the higher dosages. The upper limits of the amount leaching below a depth of 1 m were estimated at less than 3% of the dosage.

Persistance et mobilité du bromacile dans les sols de vergers.

Du bromacile a été apporté annuellement pendant six ou sept ans dans des essais effectués dans deux vergers de pommiers. A des intervalles d'une année aprés la derniére application, les concentrations ont été mesurées par chroma‐tographie gaz‐liquide, á des profondeurs variées allant jusqu'a plus d'un métre. En moyenne, il a été retrouvé 54% de la dose annuelle, ce qui correspond á une diminution de 35% de l'apport initial, dans l'intervalle d'une année. Les concentrations les plus fortes dans le profil ont été trouvées aux environs de 10 à 20 cm, ce qui indique une mobilité beaucoup plus lente que ce qui a été trouvé dans des expériences avec des couches minces. Des traces de bromacile ont été retrouvées à des profondeurs avoisinant 1 m, particuliére‐ment avec des dosages élevés. Les limites supérieures du lessivage à une profondeur inférieure à 1 m ont été estimées à moins de 3% de la dose.

Persistenz und Mobilität von Bromacil im Boden von Obstanlagen

In zwei Apfelanlagen wurde iiber sechs bzw. sieben Jahre, jährlich einmal Bromacil angewendet. In Abständen von einem Jahr nach den letzten Anwendungen wurde das Herbizid in verschiedenen Bodentiefen bis liber 1 m Tiefe gaschromatographisch nachgewiesen. Im Durchschnitt waren noch 54% der jährlichen Aufwandmenge vorhanden. Das entspricht einer Abnahme der ursprünglich ausgebrach‐ten Herbizidmenge um 35% innerhalb eines Jahres. Die höchste Konzentration wurde in einer Tiefe von etwa 10–20 cm gefunden. Die Mobilität des Herbizids war, verglichen mit seiner Beweglichkeit in Versuchen mit der Boden‐Dunn‐schicht‐Chromatographie wesentlfch geringer. Spuren von Bromacil wurden besonders bei den hoheren Aufwand‐mengen in einer Tiefe von 1 m gefunden. Es wird angenom‐men, dass die hochste Herbizidmenge, die liber 1 m tief transportiert wurde, weniger als 3% der Aufwandmenge entspricht.
European weeds and other alien species in the Subantarctic
Authors: WALTON D. W. H.
Published: July 2006

Summary: Résumé: Zusamenfassung

The species of European weeds which occur as persistent aliens on the subantarctic islands are listed. Their persistence and degree of success in establishment of populations is examined and probable means of introduction suggested for certain species. Poa annua, Cerastium holosteoides and Stellaria media appear to be the most widespread species while Poa annua is undoubtedly the most successful species. Grazing effects can materially influence the spread of introduced species, reindeer on South Georgia having brought about the establishment of pure Poa annua swards. Viable seeds of some species have been found to persist for several years, only germinating under unusual weather conditions. It is concluded that whilst Man's activities have not so far damaged irreparably the floras of any of the islands there is considerable cause for concern for the future.

Les mauvaises herbes européennes et autres espéces étrangéres dans la zone subantarctique.

On a dressé la liste des espèces européennes de mauvaises herbes qui apparaissent comme des adventices persistantes dans les îles de la zone subantarctique. Leur persistance et Ie degré de réussite dans l'établissement de population est examiné et il est suggéré quelques moyens probables d'intro‐duction pour certaines espéces. Poa annua, Cerastium holosteoides et Stellaria media apparaissent comme les espéces les plus répandues, cependant que Poa annua est indubitable‐ment I'espéce qui a le mieux réussi. Les effets du pâturage peuvent matériellement influencer la dispersion des espéces introduites, les rennes en Georgie du Sud ayant contribué a l'etablissement de pelouses monospé cifiques de Poa annua. Il a été constaté que des semences viables de certaines espéces peuvent persister pendant plusieurs années, ne germant que dans des conditions climatiques inhabituelles. Il en est conclu que si les activités de l'homme n'ont pas encore endommagd de façon irréparable les flores d'aucune des îles, il y a cependant de graves raisons d'inquiétude pour le futur.

Europäische Unkräuter tmd andere fremdiändische Arten in der Sub‐Antarklis

Die europäischen Unkrautarten die sich auf den subantarktischen Inseln eingebürgert haben, sind zusammen‐gestellt. Ihr Ausdauern und ihr Vermögen Poputationen zu bilden wird untersucht und mögliche Wege der Einbüirgerung werden für einige Arten dargelegt. Poa annua, Cerastium holosteoides und Stellaria media scheinen die am weitesten verbreiteten Arten zu sein, während Poa annua zweifelsohne die erfolgreichste Art ist. Durch Abweiden kann die Aus‐breitung der eingeführten Arten wesentlich beeinflusst werden; so entstanden auf Süd‐Georgien durch Rentiere reine Poa annud‐Rasen. Es wurde gefunden, dass die Samen einiger Arten mehrere Jahre lebensfähig bleiben und nur onter ungewöhnlichen Witterungsbedingungen keimen. Es wird gefolgert, dass die Tätigkeit des Menschen bisher auf keiner der Inseln zu irreparablen Schaden der Floren gefuhrt hat, die weitere Entwicklung gibt jedoch Anlass zur Sorge.
Persistence and movement of ethofumesate in soil*
Authors: SCHWEIZER E. E.
Published: July 2006

Persistence of ethofumesate [(±)2‐ethoxy‐2.3‐dihydro‐3,3‐dimethylbenzofuran‐5‐yl‐methansulphonate] in soil was associated with soil temperature. Ethofumesate applied at 4.5 kg/ha in November persisted about twice as long in soil as that applied the following March. In another field study, 88–91% of the herbicide had dissipated after 24 weeks in sandy loam soil, compared to 72–77% in loam soil when it was applied at rates of 2.2, 3.4, 4.5, and 9.0 kg/ha. The rate of degradation was independent of the initial rate of chemical applied. The time required for 50% of the herbicide to dissipate in sandy loam and loam soils was 7.7 and 12.6 weeks, respectively. The movement of ethofumesate in these two soils over a 24‐weeks sampling period was confined mainly to the upper 7.5 cm of the soil profile.
Adsorption et désorption de la pyrazone par quelques colloïdes organiques et minréaux
Authors: FUSI P. , CECCONI S. , Franci M. , VAZZANA C.
Published: July 2006

On a éludié l'adsorption et la désorption de la pyrazone sur des colloïdes organiques et minéraux et sur des résines échangeuses d'ions saturées par les ions H+, Na+, K+, Ca++ et Mg++. Pour ce qui concerne les adsorbants‐H, on a trouvé l'ordre d'adsorption suivant: Amberlite‐H> Dowex‐H > humus‐H> montmorillonite‐Al,H > illite‐Al,H > kaolinite‐ Al,H. Cette adsorption, qui semble etre due à des liaisons physiques et non à des mécanismes de protonation, est plus grande que celle trouvée avec des systèmes‐K, ‐Na, ‐Ca, et ‐Mg. Avec des systèmes‐Ca on a obtenu le même ordre d'adsorption: Dowex‐Ca> montmorillonite‐Ca> illite‐ Ca> kaolinite‐Ca. Contrairement à ce que nous avons trouvé pour la résine Dowex, avec la montmorillonite et l'illite, le cation saturant semble avoir un effet sur l'adsorption de la pyrazone; en effet nous avons obtenu l'ordre suivant: Ca++> Mg++> K+> Na+. Pour tons les systèmes que nous avons examinés, la désorption de la pyrazone adsorbée a été complète.
Specific microbial responses to herbicides*
Authors: GROSSBARD ERNA , DAVIES HAZEL A.
Published: July 2006

Examples from the literature and from the authors’own laboratory demonstrate that herbicides can exert adverse effects on the soil micro‐flora, depending on concentration, though often at higher rates than the herbicidal dose. Examples refer to changes in microbial growth (asulam, linuron, paraquat) and equilibrium (metoxuron), respiration and nitrification in samples from field experiments (linuron, simazine) and laboratory experiments (bentazone, glyphosate, barban, etc.), enzyme activities (urease, phosphatase; barban, chlorpropham, linuron) and the decay of sprayed vegetation (glyphosate, paraquat).
A note on the dispersal of seeds of blackberry (Rubus procerus P.J. Muell.) by foxes and emus
Authors: BRUNNER H. , HARRIS R. V. , AMOR R. L.
Published: July 2006

The monthly variation in the number of seeds of blackberry (Rubus procerus P. J. Muell.) in fox (Vulpes vulpes) faecal droppings was measured at two sites in Victoria, Australia. The maximum percentage of droppings containing seeds (89% at Dartmouth and 55% at Sherbrooke) and the maximum monthly average for the number of seeds per dropping (570 at Dartmouth and 390 at Sherbrooke) occurred in March. Droppings of emu (Dromaius novaehollandiae) collected at Dartmouth contained a mean of 2460 blackberry seeds per dropping.

Blackberry seed obtained from berries, fox droppings and emu droppings was tested for germination over a 1O‐month period. Germination commenced in spring and ranged from 22 to 35%.

It is concluded that foxes and birds are probably responsible for dispersing blackberry over large areas of Victorian bushland.
Uptake, translocation, metabolism and selectivity of glyphosate in Canada thistle and leafy spurge
Authors: GOTTRUP O. , O'SULLIVAN P. A. , SCHRAA R. J. , VANDEN W. H.
Published: July 2006

The uptake, translocation and metabolism of glyphosate [N‐(phosphonomethyl) glycine] by Canada thistle (Cirsium arvense (L.) Scop.) (susceptible) and leafy spurge (Euphorbia esula (L.)) (resistant) were examined in an attempt to elucidate the nature of the differential sensitivity. The pattern of uptake and translocation was similar in both species. Glyphosate moved readily in the apoplast and the symplast. High humidity and/or surfactant greatly increased the amount of 14C‐glyphosate absorbed and translocated over that in low humidity and/or without surfactant. No 14Cmetabolites were detected in either species 1 week after treatment with 14C‐glyphosate. More of a glyphosate spray solution containing a fluorescent dye was received and retained on Canada thistle by virtue of its growth habit than on leafy spurge. More glyphosate should therefore be available for uptake by Canada thistle and this may account for the differential sensitivity of these two species.
The vegetation of roadsides and adjacent farmland of the Mornington Peninsula, Victoria, Australia
Authors: LANE D.
Published: July 2006

A survey of the composition and structure of the vegetation of the roadside easement and adjacent farmland was made at eighteen sites on the Mornington Peninsula. Victoria, Australia. The ground cover was grass dominant at all sites, with a predominance of introduced species notably Holcus lanatus, Anthoxanthum odoratum and Briza maxima. Agrostis tenuis and Paspalum dilatatum occurred to a lesser extent. Two alien broad‐leafed species, Hypochoeris radicata and Plantago lanceolata, were abundant at most sites.

The frequency of species present on the easement was markedly reduced in the adjacent farmland; conversely, the pasture plants Lolium perenne, Trifolium repens and T. subterraneum, did not colonize the easement to any great extent.

At some sites, the native trees and shrubs had not been cleared during road construction. They were able to survive on the easement despite the influences of the adjacent road and farmland. Seedlings of all the native species were found.
Investigations into some aspects of the biology of potatoes as weeds
Authors: LUTMAN P. J. W.
Published: July 2006

The results of a survey of potato fields have shown that up to 370 000 tubers/ha may remain in the field after the potato harvest. Most of these tubers were less than 4 cm in diameter and their distribution in the soil suggests that they had fallen between the bars of the harvester elevators.

Despite high mortality during winter, substantial populations of potato plants were found in subsequent crops. Up to 50 000 sprouts/ha were recorded in a survey of several winter wheat fields. Emergence of these sprouts started in April and continued until the end of May, and in other trials new sprouts were still emerging at the end of June. Several experiments indicated that soil temperatures and moisture levels in spring and also tuber depth affected emergence; the deeper tubers emerged later. Weed potato plants in cereal crops were found to produce an average of 2 daughter tubers, thus providing a tuber population for infestations in the following year.

The results are compared with those of other workers, and their importance in the development of methods of control is discussed.
Glasshouse trials with controlled drop application of some foliage‐applied herbicides
Authors: MERRITT C. R. , TAYLOR W. A.
Published: July 2006

MCPA, mecoprop, dichlorprop, dicamba, 2,3,6‐TBA, bentazone, ioxynil/bromoxynil (a mixture), barban, difenzoquat and chlorfenprop‐methyl were applied by spinning disc in controlled drop sizes from 150‐350μm and at very low volume rates (5–45 1/ha), to the foliage of some dicotyledonous weed species or wild oats (Avena fatua L.). The same herbicides were also applied by means of conventional hydraulic nozzles at volume rates of about 200 1/ha. Most of these herbicides performed as well at very low volume rates as with the conventional application, the major exceptions being bentazone, ioxynil/bromoxynil (both of which have distinct contact effects) and dichlorprop. Comparisons between oil and water as the diluent at a very low volume rates suggest that there may be situations when oil is preferable and others when water is.
The degradation of simazine, linuron and propyzamide in different soils
Authors: WALKER A. , THOMPSON JULIE A.
Published: July 2006

Simazine, linuron and propyzamide were incubated in 18 different soils at 25°C and field capacity soil moisture content. The degradation of each herbicide followed first‐order kinetics. The half‐life of simazine varied from 20 to 44 days, that of linuron from 22 to 86 days and that of propyzamide from 10 to 32 days. The rate of linuron degradation was highly significantly correlated with soil organic matter content, clay content, soil respiration and the extent of herbicide adsorption by the soil. The rate of simazine degradation was significantly and negatively correlated with soil pH, but the rate of propyzamide degradation was not related with any of the soil factors examined.
Seed dormancy and periodicity of seedling emergence in Veronica hederifolia L.
Authors: ROBERTS H.A. , LOCKETT PATRICIA M.
Published: July 2006

Emergence of Veronica hederifolia seedlings began in mid‐October and continued into spring; few appeared from June to September. Ripe seeds shed in June were dormant but wben buried in soil outdoors developed a capacity for germination initially at low temperatures (constant4 C; daily alternations of 4‐10° and 4‐1 5 C) and later at somewhat higher temperatures, with peak germination in September‐November. During winter, spring and early summer thc germination capacity declined, to increase again in late summer and early autumn. Cyclic physiological changes thus occur in seeds of V,hederifolia present in the soil, with which lhe consistent seasonal periodicity of seedling emergence is associated.

In dry storage ihe capacity for germination progressively increased, but alter 12 months there was a sharp decline in germination at 4° C. Few seeds germinated at 20° C, but moistening with GA 4/7; brought about complete germination at this temperature.
Impact of 2,4‐D on Ceuthorhynchidius horridus (Coleoptera: Curculionidae) and their compatibility for integrated control of Carduus thistles
Authors: TRUMBLE J. T. , KOK L. T.
Published: July 2006

Acute and chronic effects of spring application of 2,4‐D on adult C. horridus (Panzer) were examined by determining dose‐mortality response and adult vitality. LC50 values for males (70.2 kg/ha) and females (61.4 kg/ha) corresponded to 41.7 and 36.6 times, respectively, the recommended application rate of 1.68 kg/ha. Survival of weevils treated with 1.68 kg/ha was not different from untreated controls, but higher doses (16.8–147.8 kg/ha) caused significantly greater mortality. Adult vitality, measured by number of feeding marks per weevil and rate of weight change. was unaffected by the herbicide. When thistle infested fields were sprayed with 1.68 or 2.24 kg/ha of 2,4‐D the host plants died, but the survival, reproduction, and population increase of C. horridus were not affected.
A study of competition between seedlings of gorse (Ulex europaeus L.) and perennial ryegrass (Lolium perenne L.) by means of a replacement series experiment
Authors: IVENS G. W. , MLOWE F.
Published: July 2006

Competiton between seedlings of gorse (Ulex europaeus L.) and perennial ryegrass (Lolium perenne L cv. Grasslands Nui) was studied in a replacement series experiment under glasshouse conditions. Without cutting, the shoot growth of gorse in monoculture exceeded that of ryegrass over 22 weeks but was reduced more by competition from ryegrass than the grass growth was reduced by competition from gorse. The root system of gorse was small compared with that of ryegrass and was further reduced by competition. Cutting three times at 2 or 4 cm reduced the total growth of both species and gorse was affected more than ryegrass. With grass, however, the ‘growth between succeeding cuts declined faster than that of gorse and in the final harvest period, gorse in monoculture oulyielded ryegrass. The relative crowding coefficients of gorse were low compared with those of ryegrass and their products consistently exceeded 1.0. The results are discussed in relation to lirmiting seedling establishment of gorse in the field.
Interaction between glyphosate and various herbicides for broadleaved weed control
Authors: O'SULLIVAN P.A. , O'DONOVAN J.T.
Published: July 2006

The effects of several herbicides for broadleaved weed control on glyphosate (n‐phosphonomethyl glycine) phytotoxicity to wheat (Triticum aestivum L.), barley (Hordeum vulgare L.) and wild oats (Avena fatua L.) were studied in the greenhouse. In tank mixtures, dicamba (3,6‐dichloro‐o‐anisic acid), 2,4‐D (2,4‐dichlorophenoxy‐acetic acid) and bromoxynil (3,5‐dibromo‐4‐hydroxy benzonitrile) reduced the phytotoxicity of threshold rates of glyphosate on all three species. With increasing rates of the herbicides for broadleaved weed control relative to a fixed rate of glyphosate, there was a general trend towards increased antagonism. Increasing glyphosate rates above the threshold level in mixtures containing a fixed rate of herbicides for broadleaved weed control overcame the antagonism. Both the inert and active ingredients of 2,4‐D amine and ester appeared to be involved in the antagonism. There was no reduction in glyphosate phytotoxicity on the annual grasses when 2,4‐D or bromoxynil were sprayed sequentially at various times in relation to glyphosate. When droplets of bromoxynil and glyphosate were placed side by side on a leaf, glyphosate phytotoxicity was not reduced, whereas when the two herbicides were mixed and applied as one droplet, considerable reduction in glyphosate phytotoxicity occurred. These results suggest that the reduction in glyphosate phytotoxicity caused by tank mixing with herbicides such as 2,4‐D, bromoxynil and dicamba may be due to a physical or chemical incompatability within the tank mixture rather than to a biological interaction in the plant.
Residues of atrazine and its metabolites after prolonged usage
Authors: KHAN S. U. , SAIDAK W. J.
Published: July 2006

Atrazine was applied to a field planted to corn (Zea mays L.) for 20 consecutive years at rates ranging from 1.40 to 2.24 kg/ha. Analysis of soil samples taken 6 and 12 months after the final application showed the presence of residues of the parent compound and its mono dealkylated hydroxy analogues. Shoots and roots of oat (Avena saliva L.) plants grown in the field contained hydroxyatrazine (2‐hydroxy‐4‐ethylamino‐6‐isopropylamino‐s‐triazine) and one of its mono dealkylated analogues in the conjugated form. Oats and timothy (Phleum pralense L.) grown in treated soil in a growth cabinet showed similar results. The data suggest that long‐term annual applications of atrazine for weed control in corn result in the persistence of some of its degradation products, mainly hydroxylated analogues, in soil I year after the final herbicide application. It is conceivable that such residues may enter into the food crops planted in atrazine‐treated soil in the year or years following the cessation of a long‐term treatment.
The kinetics of linuron and metribuzin decomposition in soil using different laboratory systems
Authors: HANCE R.J. , HAYNES R. A.
Published: July 2006

Rales of linuron and metrihuzin breakdown in soil were studied in four laboratory systems: fresh soil incubated in polyethylene bags; air‐dry soil resetted and incubated in polyethylene bags; complete soil cores; a perfusion apparatus. The apparent order of reaction. estimated using a power rate equation, varied from 0.45 to 2.90 and was not consistent with respect either to the compounds or the incubation methods. It is possible that diffusion controlled processes may be involved in producing this variation. The results of six of the eight experiments could be fitted to the first order rate equation (P= 0.01). When the first order model was statistically valid, half‐life times were within 50% of the time for 50% disappearance calculated wiih the power rate expression but there were differences up to five‐fold in the times for 90% disappearance, calculated by the two methods. It is suggested that decomposition experiments giving orders of reaction greater than I require verification in more than one experimental system
Ash from rice stubble inactivates thiobencarb and molinate
Authors: TOTH J. , MILHAM P. J. , RAISON J. M.
Published: July 2006

The vegetative growth of Japanese millet (Echinochloa utilis Ohwi et Yabuno) was much lens reduced by pre‐emergent treatments of thiobencarb (S‐eithyl hexahydro‐1,4‐azepine‐l‐thiolcarbamate) and molinate (S‐(4‐chlorobenzyl)‐N.N‐diethylithiolcarbamate] when the herbicides were applied at <4 l a.i. ha−1 over rice stubble ash. The effcct was caused by adsorption of the herbicides onto activated carbon in the ash and occurred alike in field and pot experiments.

The reduction in herbicide activity was quantified in the pot experiment. There the ash rendered at least 60% of the applied herbicide biologically unavailable.