摘要:

Zusammenfassung.Im modifizierten logarithmischen Feldversuch mit ‘Kreuzparzellen’ wurden die Wechselbeziehungen zwischen Vorsaatbehandlung mit NaTCA bzw. Dalapon und Vorauflaufbehandlung mit Pyrazon bzw. Lenacil untersucht. Für jedes Kombinationspaar (NATCA+Pyrazon, Dalapon+Pyrazon, NaTCA+Lenacil, Dalapon+Lenacil) entstanden sechunddreissig Varianten. Dabei zeigte sich, dass auch NaTCA und Dalapon allein eine gewisse Wirkung gegen dikotyle Arten haben. Mit Steigenden Aufwandmengen an NaTCA bzw. Dalapon nahm in der Kombination mit Pyrazon bzw. Lenacil die Unkrautwirkung und in geringerem Masse auch die Phytotoxizität gegen die Rüben zu. Da bei der kombinierten Anwendung der genannten Vorsaat‐ und Vorauflaufherbizide die Empfindlichkeit der Rüben weniger Stark zunahm als die der Unkräuter, wurde zumindest unter den im Versuch gegebenen Bedingungen die Selektiviät nicht vermindert.The interaction between herbicides applied before sowing and pre‐emergence

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01484.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Summary.Senescent, expanded or expanding leaves of lettuce plants were treated individually with MCPA. The subsequent development of auxin‐induced symptoms throughout the plants was recorded. The number of leaves affected and the severity of the symptoms increased with application to the less mature leaves. In addition more leaves were affected when the application was made to larger plants than to smaller ones. These results were associated with absorption/translocation differences in the leaves of different ages, and in their spatial relationship to tissues at particularly susceptible stages of development. In further experiments, applications of similar weights of MCPA to lettuce plants in droplet sizes of approximately 100 μ and 500 μ were compared. There were consistent trends for the small droplets to produce greater effects.Quetques effets de la taille des gouttelettes et de leur position sur la reaction de la laitue à des doses sub‐létales

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01485.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Summary.Successive bioassays during 1966 and 1967 showed that simazine degradation reached 80% in 11 and 22i weeks, respectively, in soil from the 0–2 in. horizon of a gooseberry experiment to which simazine had been applied annually in the absence of soil cultivation from 1960. Where an annual farmyard‐manure mulch was also applied, the same loss of residual activity was reached in 10 and 20 weeks. This mulch initially reduced the simazine level rapidly compared to that of unmulched soil, but the subsequent rates of degradation were similar. The rate of simazine degradation depended more on environmental conditions each year than on soil type. The results indicate that an annual simazine degradation in excess of 80% can be expected in Loughgall soils in conditions of non‐tillage. Even if simazine applications continued indefinitely at an annual dose of 20 Ib/ac–the current dose in the gooseberry experiment–a large residue accumulation could not occur with or without a mulch.Persistance de la simazine appliquée annuellement en l'absence prolongée de faço

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01486.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Summary.The effects were determined of paraquat dichloride and Lissapol NX, consutuents of the commercial formulation Gramoxone W, on the rate of oxygen uptake by cultures ofFusarium cutmanmtandTrkkoderma viride.When applied separately, paraquat dichode was less inhibitory than the wetting agent; when applied together, the inhibitory effect was greater than the sum of those obtained separately. Synergism was also observed between paraquat dichloride of commercial purity and a solution containing the additives used m Gramoxone W but without the paraquat dichloride. This effect is thought to be due to increased permeation of paraquat dichioride into fungal mycelia in the presence of a wetting agent. Older cultures were less affected than younger ones by the coniponents of Gramoxone W. The results suggest that the additives used in formulating herbicides may be critical in determining fungitoxicity.Effets des constituants du Gramoxone W sur les taux de respiration de champignons du sol

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01487.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Summary.An investigation was made of a now herbicide, 2–amino‐3–chloio‐1,4–naphthociuinone (ACNQ,), which appears to be promising for the control oiEchinochloa crus‐galli(L.) Beauv. in transplanted paddy rice [Oryza sativaL.).In pot experiments in the glasshouse, seedlings ofEchinochloaat different stages of growth were killed by ACNQ, at doses equivalent to 2–4 kg/ha (applied as granules) if they were submerged, but not if the shoots emerged above water. Activity was increased more by raising the level of water in the pot than by increasing the dosage. Emergent rice seedlings were little affected by ACNQ, up to 8 kg/ha, and the observed selectivity is considered to be due mainly to differences in plant height in relation to depth of water.In laboratory experiments with rice seedlings grown without soil, the activity of ACNQ again increased with the depth of solution. Conversely, at a standard solution depth, there was a reduction in damage with advancing stage of growth, and the chemical had little effect once the leaf tip was above the solution surface.The rate of leaching of ACNQ. through a sandy soil was slow and, at a dose of 2 kg/ha, persistence was about 15 days.In evaluating new herbicides for paddy rice it is suggested that screening tests arc necessary on submerged as well as non‐submerged plants.Activité herbicide de la 2–amino‐3–chloro‐1,′4–naphtoquimne. I. Activité herbi

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01488.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Summary.Electron‐capture gas chromatography was used to detect tri‐allate residues in persistence studies with two soils. At rates equivalent to 0–75, 15 and 3 Ib/ac, 50% of the amount applied was degraded in 8–11 weeks at 25°C in moist Regina heavy clay and Weyburn loam. No loss occurred in sterile soils, indicating that microbial degradation may be a, major factor contributing to tri‐allate breakdown.When aqueous solutions buffered at pH 4–8 were held at 25° G, only 10–15% of the tri‐allate was chemically degraded during 24 weeks.At the normal field rate of 1·25 Ib/ac, tri‐allate was not readily leached. From soil columns of Weyburn loam, 5–7% was eluted by 9 in. of water; with clay the corresponding value was 12–13% of the amount applied. When field plots were sprayed with 125 lb/ac in April, tri‐allate could still be detected until the soil froze in November.Facteurs agissant sur la perte

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01489.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Summary.The persistence of ten herbicides in soil was tested in the glasshouse over a 5–month period, using an oat bioassay. Simazine and diuron were highly persistent, atrazine persistent, fluometuron, trifluralin, bromacil and noruron moderately persistent, and pyrazon, prometryne and ametryne of short persistence. Six of these herbicides were also included in a field experiment consisting of logarithmically sprayed strips on which oats were sown at ten intervals of 1 month; changes of herbicidal activity with time were evaluated by measuring the length of the strip showing herbicidal injury. Results corroborate those of the glasshouse experiments except for trifluralin which was more persistent in the field. Disappearance curves were generally sigmoidal. The more persistent compounds showed a long period of slow disappearance followed by rapid disappearanc

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01490.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Résumé.L'absorption initiale et la migration du14G‐métobromuron se produisirent avec une vitesse identique dansSinapis arvensisL. etVeronica persicaPoir., mais, avec un traitement plus prolongé, [‘accumulation par unité de surface foliaire fut plus importante chezVeronica persica. II n'y eut pas d'accumulation ultérieure dans les racinrs, les tiges, les pétioles ou les nervures foliaires principales des deux espèces après le début de diminution de la radioactivité. II y eut toutefois une accumulation continue sur le bord des feuilles. Aucune relation ne peut être êtablie entre l'absorption et la migration d'une part, et les différences de sensibilityé des deux especes vis‐i‐vis du mitobromuron d'autre part.L'absorption et la migration du14C‐métobromuron apparurent légèment plusrapides chezSolanum tuberosum, variété Isola que chez la variété Delos. Ceite différence disparut rapidement et la concentration finale par unité de surface fut plus élevée chez Delos que chez Isola. L'accumulation de métobromuron dans les racines, les tiges, les petioles el les nervures des feuilles cessa lorsqu'une concentration particulièere fut alteinte. Dans les portions du limbc entre les nerures et au bord des feuilles, l'accumulation of poursuivit durant toutc I'expérience. Aucune relation ne peut être e'tablie entre l'absorption et la migration d'une part et la sensibilité des deux cultivars d'autre part.Les autoradiogrammes montrèrent que, dans les expériences où le14C‐metoéromuron fut applique sur les racines et sur les feuilles deSinapis arvensis, deVeronica persicaet des deux variétés de pomnies de terre, le métobromuron est, dans des conditions normales, ohligatoirement transporté dans le xylème.Summary.Initial uptake and transport of14C‐metobromuron occurred equally rapidly inSinapis arvensisL. andVeronica persicaPoir., but with longer treatment, accumulation per unit leaf area was greater inV. persica.There was no further accumulation in the roots, stems, petioles or main leaf veins of either species after the initial increase in radioactivity. There was, however, continued accumulation in the leaf margins. No relation was found between uptake and translocation and the differential susceptibility of the two species to metobromuron.Uptake and translocation of14C‐metobromuron was rather more rapid inSolanum tuberosumL. cv. Isola than in cv. Delos. This difference soon disappeared and the final content per unit leaf area was greater in cv. Delos than in cv. Isola. Accumulation of metobromuron in the roots, stems, petioles and leaf veins ceased when a particular concentration had been reached; in the interveinal areas of the legal margins accumulation continued throughout the experiment period. No relation was found between uptake and translocation and the differential susceptibility of the two cultivars.Evaluation of the autoradiograms from experiments with root‐ and leaf‐applied14C‐metobromuron inSinapis arvensis, Veronica persicaand the two potato varieties indicated that under normal cond

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01491.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Summary.The decomposition of seven urea herbicides byBacillus sphaericuswas studied. Experiments with14C‐labelled monolinuron demonstrated that monolinuron was degraded by removal of CO2from the ureido portion of the molecule and leaving the /Kchloroaniline moiety. Tests with monuron, diuron, monolinuron, linuron, metobromuron, fluometuron and methabenzthiazuron indicated thatB. sphaericuswas only able to decompose the methoxy compounds monolinuron, linuron and metobromuron in this way. All compounds were identified by infrared spectroscopy. A pathway for degradation of the herbicides byB. sphaericusis propose

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01492.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY

摘要:

Résumé.Une nouvelle urée substitutée le méthbenzthiazuron (N‐benzothiazol‐2‐yl‐NN′‐diméthylurée), a été utilisée en culture hydroponique deTriticum sativum cv.Vilmorin 27. La substance active selon qu'elle est pure ou sous sa forme commerciale provoque des inhibitions de croissance différentes. On a mis en évidence le röle joué par les ingrédients théoriquement inactifs ajoutés à la substance active. L'utilisation de diquat marqué permet de conclure à la présence de l urée dans i'ensemble des tissus. La cinétique de la réponse suggére un phénoméne de détoxification. C'est la concentration extérieurc aux racines

ISSN:0043-1737    

DOI:10.1111/j.1365-3180.1969.tb01493.x

出版商:Blackwell Publishing Ltd    

年代:1969

数据来源: WILEY