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Notes: [Auszug] A further series of experiments was then carried out in which the amount of adsorption was directly determined using xanthate labelled with carbon-14, and compared with the amount of xanthate removed as determined here. The combined measurements showed a discrepancy, in that, of the original ...

Notes: Summary. The following factors influencing the selectivity of di-allate against Avena spp. in spring wheat and barley have been investigated in seven field experiments: (a) depth and degree to which the herbicide is mixed with the soil, (b) time of application of the herbicide relative to sowing the crop, (c) implement used to incorporate the herbicide with the soil, (d) depth of germination of the Avena spp.Di-allate and tri-allate incorporated relatively deeply before drilling the crop controlled Avena spp, much more effectively than when incorporated shallowly by chain-harrowing after drilling, but the pre-drilling treatments were also more toxic to the crop.In wheat, di-allate incorporated shallowly after drilling was slightly more selective than when incorporated more deeply before drilling but in barley there was no evidence to favour either time of application. Pre-drilling treatments incorporated by a rotary cultivator were a little more selective to both crops than those incorporated by springtine harrows.Tri-allate was more selective than di-allate, in wheat, when incorporated before drilling the crop. There was no evidence regarding its selectivity as a post-drilling treatment.The initial distribution of the herbicide in the soil, after incorporation by: (a) spring-tine harrowing once, (b) rotary cultivating once or twice, or (c) chain harrowing once, was measured in one experiment by a fluorescent tracer technique. The results showed that ordinary farm implements give a very uneven distribution (both vertical and lateral) of herbicide in the soil.In the field, di-allate and tri-allate incorporated with the soil shallowly after drilling proved to be less selective and less active than similar treatments in the glasshouse. It is suggested that the reduced selectivity of these treatments in the field is due to loss of herbicide by vaporization and retention of the herbicide by the soil under dry conditions.The importance of the various factors influencing the selectivity of di-allate and triallate in the field is discussed in the light of the results of these experiments and those of other research workers (particularly Parker, 1963).Essais de plein champ sur la phytotoxicité sélective du di-allate envers les Avena spp. dans le blé et l'orge

Notes: Over a period of three seasons the effectiveness of rouging wild oats in cereal crops with a patented herbicide glove was compared with hand pulling. Time spent by one operator in searching for the wild oats was found to remain relatively constant at 1.25–1.5 h/ha over a wide range of wild oat populations. If this searching time was excluded, treatment of the actual wild oat panicles was about three times as fast with the glove (1450/h) as by hand-pulling (538/h). The implications of this and of the saving in time spent in carrying off and disposing of’pulled’ wild oats are discussed.Solutions of 5% and 10% w/v glyphosate applied to either the stem or the panicle of the wild oats prevented the formation of viable seed. It did not, however, prevent some inviable wild oat seed appearing in the harvested grain; without additional cleaning these would have prevented the sale of the grain for seed but not into E.E.C. intervention. Extirpation de la folle-avoine Durant one période de trios saisons, les auteurs ont compare l'efficacité de l'extirpation de la folle avoine dans des cultures de céréales au moyen d'un gant herbicide breveté et en pratiquant I'arrachage manuel. Le temps passé par un opérateur à la recherche des pieds de folle-avoine s'est révélé relativement constant: 1,25 à 1.5 h/ha pour un large échantillonnage de populations de folle-avoine. Si l'on enlève ce temps de recherehes, I’operation sur les panicles présentes de folleavoine a été environ 3 fois plus rapide avec le gant (1 450/h) quä la main (538/h). Les conséquences de ce résultat et de lëconomie de temps passéâ transporter et â détruire les plants de folleavoine arrachees sont discutées.Des solutions de glyphosate à 5% ou 10% (poids pour volume) appliquées soit sur la tige soit sur la panucle des follesavoines ont empèche la formation de semences viables. Toutefois, cette opération n'empeche pas la présence d'un certain nombre de semences non viables de folle-avoine dans le grain recolté; sans nettoyage supplémentaire, ces graines d'adventices auraient empéché la commercialisation du grain récolté comme semence, mais pas à I'intérieur de la C.E.E. Manuelle Bekämpfung von Flughafer über drei Vegetationsperioden wurde die effizienz der manuellen Flughaferbekämpfung in Getreidebestanden mit hilfe eines ‘herbizid-Handschuhs’ verglichen mit dem Aufwand beim Jäten von Hand. Die von einer Arbeitskraft benötigte Zeit für das auffinden der Flughaferpflanzen blieb über einen weiten Bereich der Besatzdichte an Flughafer mit 1,25–1,5 h/ha verhältnismässig konstant. Lässt man diesen Zeitaufwand uberücksichtigt, dann erfolgte die Behandlung der Flughaferrispen mit dem Handschuh etwa dreimal so schnell (1450/h) wie durch Jäten von hand (538/h). Die hieraus sowie aus der Ersparnis an Zeit, die sonst für Abtransport and Ablagerung der gejateten Flughaferpflanzen benötigt worden wäre, zu ziehenden Folgerungen werden diskutiert.Lösungen von 5% oder 10% (Gew./Vol.) Glyphosat entweder am Halm oder an der Rispe der Flughaferpflanzen angebracht. verhinderten die Bildung von keimfahigen Samen. Sie konnten aber nicht verhindern. dass dem Getreide nach der Ernte einige nicht keimfähige Flughafersamen beigemengt waren. Hierdurch bedingt wäre ohne zusätzliche. Reinigung ein Verkauf des Getreides als Saatgut nicht möglich gewesen, wohl aber ein Verkauf an die EG-Interventionsstelle.

Notes: In three experiments at two sites the influence of date of application, dose and additives on activity of asulam on bracken (Pieridum aquilinum) was investigated Asulam was only effective when it was applied to live bracken foliage. Of the foliar treatments. July applications were more effective than those applied in June or September. A dose of 1-1 kg/ha asulam gave inadequate control but 2-2 kg/ha and above applied in July gave good control. Increasing the dose increased the degree of control and also lowered the rate of regeneration. Adding 0·5%, Agral 90 or tributyl phosphate at 0·25%, and 0·5%, with or without Agral 90 at 0·5%, had little useful effect on asulam activity, 4·5 kg/ha dicamba or aminotrizole given in July were less effective than asulam at 2·2 kg/ha. Dicamba was the most active of the herbicides tested in the absence of viable bracken foliage. Facteurs influençant l'action de l'asulame sur la fourgére aigle (Pteridium aquilinum (L.) Kuhn)Dans trios essays studés en deux endroits différents, les auteurs ont étudié l'influence de la date d'application de la dose et de divers additives sur l'efficacité de l'asulame contre la fourgére aigle (Pteridium aquilinum). L'asulame n'a été efficace que lorsqu'il a été appliqué sur le feuillage vivant de la fourgére. Parmi les traitements foliaires, ceux effectués en juillet ont été plus efficacies que ceux effectués en juin ou septembre. Une dose d'asulame de 1.1 kg/ha n'a pas n'a pas donné de bons résultats, mais la dose de 2.2 kg/ha appliquée en juillet s'est montrée efficace. L'accroissement de la dose a augmenté l'efficacité et a baissé le taux de régénération. L'addition d'Agral 90 á 0.5% ou de tributyl phosphate á 0.25% et 0.50% avec ou sans Agral 90 á 0.50% n'a pratiquement pas eu d'influence sur l'activité de l'asulame. Une dose de 4.5 kg/ha de dicamba ou d'aminotriazole apportée en juillet s'est montrée moins efficace que l'asulame à 2.2kg/ha. Le dicamba a été le plus efficace des herbicides essayés sur la fougére en l'absence de feuillage vivant. Einflussgrössen bei der Bekämpfung von Adlerfarn (Pteridium aquilinum (L.) Kuhn) mit AsulamIn drei Experimenten an zwei Standorten wurde der Einfluss von Bekämpfungszeïtpunkt, von der Aufwandmenge und von Additiven auf die Wirkung von Asulam auf Adlerfarn (Pteridium aquilinum) unterucht. Asulam Zeigte nur dann eine Wirkung, wenn es auf lebendes Blattwerk des Farns ausgebracht wurde. Blattbehandlungen im Juli waren erfolgreicher als solche im Juni order September. Aufwandmengen von 1.1 kg/ha. Asulam führten zueinem unzulänglichem, von 2.2 kg/ha und darüber. im Juli ausgebracht, zu einem guten Bekämpfungserfolg. Mit zunehmender Aufwandmenge wurde der Bekämpfungserfolg verbessert und die Regenerationsrate verringert. Die Zumischung von 0.5% Agral 90 order von 0.25% und 0.5% Tributylphosphat mit order ohne Zusatz von 0.5% Agral 90 zeigten nur einen geringen Nutzeffeki auf die Asulamaktrivität. Dicamba order Aminotriazol (4.5 kg/ha). im Juli ausgebract, war weniger wirkungsvoll als Asulam mit 2.2 kg/ha. Von den Herbiziden, mit denen bei Nichtvorhandensein lebender Farnblätter Versuche angestellt wurden, war Dicamba das aktivste.

Notes: Summary. The phytotoxicities in a number of soils of lenacil, linuron, prometryne and simazine to two indicator plants were determined in field and glasshouse experiments. The results were compared with estimates of the adsorption capacity of the soils obtained by two methods using dimethylaminobenzaldehyde as a model adsorbate. The possible influence of other soil properties was also considered.One of the adsorption measurements had some predictive value for glasshouse behaviour but was not markedly superior to soil organic carbon content for this purpose. None of the factors studied was usefully correlated with field performance. Results from field experiments in spring were poorly correlated with those from similar experiments in autumn. Neither set of field results related closely to those obtained in the glasshouse. It is concluded that the influence of climate was more important than that of soil type.La phytotoxiciti de quelquts herbicides dans des experiences en pots et en plein champ, en relation avec les propriétés du sol

Notes: Summary. In field experiments extending over the period 1964–68 wettable powder and water soluble formulations of asulam and M & B 8882 were applied to a range of grass species in summer and autumn. Phleum pratense L., Dactylis glomerata L., Holcus lanatus L., Agrostis tenuis Sibth. and Poa trivialis L. were more susceptible than Lolium perenne L., Festuca pratensis Huds. and Festuca rubra L., although effects were more persistent on H. lanatus than on the other species. Trifolium repens L. (white clover) was more resistant to M & B 8882 than to asulam, particularly in July. The pattern of selectivity was similar with summer and autumn treatment, but effects were slower to develop in the autumn.Sélectivité des herbicides a base de carbamate de benzène sulfonyle entre différentes espèces de graminées et le trèfle

Notes: Blackgrass (Alopecurus myosuroides Huds.) was controlled by 2 kg/ha of metoxuron in glasshouse trials while winter wheat, cultivar Cappelle Desprez, tolerated 4 kg/ha. Blackgrass was controlled by 1.2 kg/ha of chlortoluron. Winter wheat previously damaged by freezing was injured by 2.5 kg/ha of chlortoluron applied at an early stage. Seedlings not exposed to freezing were not damaged by 2.5 kg/ha applied at the 4- and 5-leaf stage.Breakdown of chlortoluron and metoxuron in the soil was attributed, in part, to microbial action. More than one-third of the chlortoluron applied at 2 kg/ha disappeared in 6 weeks when applied in early spring while one half disappeared in 3 weeks when applied 2 months later. The bioassay, used to determine the amount of chlortoluron or metoxuron in the soil, was found to be adequate for metoxuron in only one of three soils.The bioassay results, for both herbicides, were affected by the addition of calcium carbonate to the soil, by sterilization of the soil, and by leaching. In comparisons of results in two sandy loams and a clay loam, the observed differences could not be altogether accounted for by differences in pH nor by changes in adsorption of metoxuron. When perennial ryegrass was grown in sandy loam, and treated with metoxuron before or after emergence, different watering regimes did not give any difference in weight of top growth.

Notes: The phytotoxicity of 10% w/w tri-allate granules to emerged plants of Avena fatua L. and wheat was investigated in the glasshouse, and to A. fatua alone under outdoor conditions. Tri-allate was applied at 1.68 and 3.36 kg a.i./ha using two patterns of granule distribution (1) the granules uniformly distributed over the soil surface and (2) the same weight of granules as in (1) but applied only to a central area of the soil surface. Wheat was very tolerant of high concentrations of tri-allate. Under optimum conditions of temperature and soil moisture in the glasshouse phytotoxic effects on wild oats were visible within 6 h and coleoptile or primary leaf entrapment was observed within 3 to 4 days of treatment. Phytotoxic effects of tri-allate were detectable at distances up to 12 cm from the site of restricted-granule application, although beyond 8 cm the effect was sub-lethal. On a sloping soil surface (1:8 gradient) the dispersal of tri-allate was approximately the same upwards or downwards from the site of herbicide application. Under outside conditions where the mean temperature was about 5 C tri-allate dispersal was sub-lethal beyond 3 cm although it evidently occurred primarily as vapour.

Notes: Abstract Cells of the red alga Cyanidium caldarium were preincubated with 5 mmol 1−1 levulinic acid (LA) and subsequently incubated with 14C-labelled haem (5.67 Bq nmol−1). Phycocyanin was isolated. The specific radio-activity of its chromophore phycocyanobilin (PCB) was determined after cleavage and purification by thin layer chromatography. The percentage of PCB formed from labelled haem within 0.5 h was considerably higher in LA treated cells than in non-treated controls. This difference disappeared after prolonged incubation (16.5 h) with haem. The results are interpreted as possible incorporation of haem into preexisting apoprotein.