摘要:

AbstractThe distribution and persistence of chlormequat was determined chemically in chlormequat treated potato plants and in the progeny from their tubers.Chlormequat penetrated into the leaves, was translocated to the tubers and accumulated in the underground parts. Potato tubers harvested from chlormequattreated plants produced temporarily dwarfed plants.In the progeny of tubers, the compound was translocated to all parts of the plant, the highest amounts being found in the underground parts. A loss of only 18 ± 2% occurred between planting the seed tubers and harvesting the potato plants 2 months later

ISSN:0031-613X    

DOI:10.1002/ps.2780040502

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractThe adsorption of paraquat dichloride (1,1′‐dimethyl‐4,4′‐bipyridylium dichloride) on a soluble sodium humate fraction of a Fenland soil was studied by gel filtration (on Sephadex G10 and G100) and by ultrafiltration (through an Amicon Diaflo UM‐2 ultrafilter). Both methods depend upon the separation, on a molecular weight basis, of the unadsorbed molecules of herbicide from the adsorption complex (consisting of polymeric organic materials and the adsorbed paraquat). Separations were obtained on columns of Sephadex G10 (Method I) and in the ultrafiltration experiments (Method II), and isotherms were prepared from data for adsorption in water (by Method II) and in sodium chloride (by Methods I and II) solutions. Results from the two methods were comparable over the concentration range examined. The increased adsorption of paraquat by Na+‐compared with Ca2+‐humate is explained on the basis of the selectivity sequence of humate for exchangeable cations. Attempts to prepare isotherms from gel filtration data, for the adsorption of paraquat on two soluble model humic polymers (polyacrylic acid and a polymer prepared by the oxidative coupling of benzoquinone and ammonium chloride) were unsuccessful because binding to the gel matrix did not permit quantitative recoveries of the adsorption complexes.Paraquat was adsorbed to the same extent on each of four fractions of Na+‐humate separated

ISSN:0031-613X    

DOI:10.1002/ps.2780040503

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractA method is described for the determination of dimetridazole (1,2‐dimethyl‐5‐nitroimidazole) in pig tissues. The final estimation is made by direct current polarog

ISSN:0031-613X    

DOI:10.1002/ps.2780040504

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractResidues of dimetridazole (1,2‐dimethyl‐5‐nitroimidazole) in the tissues of pigs after administration of the drug are reported. Three dosing regimes were examined, administration of 0.05% dimetridazole in the feed for a period of 1 month, administration of 0.05% dimetridazole in the feed for a period of 2 months, and administration of 0.05% dimetridazole in the drinking water for a period of 1 week. The maximum drug level found was 6.9 μg/ml in the plasma of a pig after one week's medication with dimetridazole in the drinking water. Depletion of the drug was rapid and 48 h after the withdrawal of medication tissue levels of the drug were invariably less than 0.

ISSN:0031-613X    

DOI:10.1002/ps.2780040505

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractSpring wheat (Triticum aestivumL. “Caribo”) was grown in vermiculite containing methabenzthiazuron (N‐(benzothiazol‐2yl)‐NN′‐dimethylurea) presowing. Effects of the herbicide on plant development and plant composition were analysed up to an age of 4 weeks.Inhibition of photosynthetic oxygen evolution represented the primary effect induced by the herbicidal treatment and led to a decreased concentration of soluble reducing sugars. Photosynthetic activity however recovered after 3 weeks and even increased above control values. Secondary effects following methabenzthiazuron treatment included a delayed chlorophyll breakdown, a decreased chlorophylla/bratio, enlarged chloroplasts, an increased concentration of soluble amino acids and of soluble protein, and an increasedin vitronitrate reductase activity. These responses are taken to indicate an increased photosynthetic and metabolic capacity in methabenzthiazuron treated wheat plants.Comparable results can be obtained with plants grown at low light intensities. It is concluded that the “physiological effects” observed in wheat plants after treatment with methabenzthiazuron are similar to a natural adaptation reaction to low light intensities. It is assumed that this adaptation reaction is caused by a low concentration of soluble reducing sugars.Experiments with plants growing at different light intensities indicated that effects due to herbicidal action were more pronounced at high light intensities.Measurements on daily fluctuations revealed a peak around noon for the sugar content and the nitrate reductase activities measuredin vivoas well asin vitro. In vivonitrate reductase activity in plants treated with 5 parts/million methabenzthiazuron was very low, presumably because of lack of sugars for the production of NADH. The protein concentration was increasing and the amino acids were decreasing during the day in herbicide treated plants, possibly indicating increased protein synthesis in the light in plants treated with m

ISSN:0031-613X    

DOI:10.1002/ps.2780040506

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractTotal uptake of linuron by wheat seedlings in nutrient solutions was close to that expected from the product of the amounts of water transpired by the plants and the concentrations of herbicide in solution. Uptake from 19 different soils was less than the amount supplied by mass‐flow when the concentrations of linuron in the soil solution were estimated from slurry adsorption measurements. Using a pressure‐membrane technique, it was shown that the actual soil solution concentrations of linuron were less than those estimated, and following rewetting of pressure‐membrane samples, the rate of redistribution of linuron between the adsorbed and solution phases was slow. The results suggest that under the conditions of the uptake experiments, the systems were not in equilibrium, and show that the rates of adsorption and desorption of linuron may be important in determining its availability to p

ISSN:0031-613X    

DOI:10.1002/ps.2780040507

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

Abstract2‐2H‐5‐Benzyl‐3‐furylmethyl esters exclusively are obtained from an exchange reaction of the parent esters with deuterium oxide and a trace of acid (n.m.r. and mass spectrometric control). Similarly, with tritiated water, 6 insecticidal esters of 5‐benzyl‐3‐furylmethyl alcohol give the corresponding [2‐3H]esters, each with specific activity of app

ISSN:0031-613X    

DOI:10.1002/ps.2780040508

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractThe procedures involve the removal of captafol, captan or endosulfan spray deposits from the plant surfaces with solvent and their measurement by g.l.c. In contrast to residue analysis, clean‐up procedures are avoided and the speed of the methods enable large numbers of samples to be processed in the monitoring of initial spray deposits and the subsequent redistribution or loss in relation to the efficiency of spray application techniques. Recoveries of captafol and captan suspension deposits from glass were greater than 96%: recoveries of emulsion deposits from plant surfaces were greater than 95% for captafol, 93% for captan and 96% for endosulfa

ISSN:0031-613X    

DOI:10.1002/ps.2780040509

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractBromoxynil octanoate labelled with14C in theringor in thecyano‐group was applied to wheat seedlings at the two‐leaf or fully‐tillered stage and at rates equivalent to up to 16 oz a.i./acre. The plants were grown either in environmental chambers under controlled conditions for up to 28 days, or outdoors under field conditions for various periods up to harvest. Initially, elimination of radioactivity occurred more rapidly with bromoxynil‐cyano‐[14C]‐octanoate than with bromoxynil‐ring‐[14C]‐octanoate, indicating metabolic attack on thecyanogroup. Under outdoor conditions withring‐[14C]‐herbicide applied at the two‐leaf stage, only 12% of the radioactivity was retained after 28 days, principally in the treated leaves. When application was made at fully‐tillered stage, about 33% of the14C was retained after 56 days, almost entirely in the treated senescent leaves at the base of the plant. There was very little translocation of the herbicide or of any major metabolite.The level of radioactivity in harvested grain and in straw more than 7.5 cm above the ground was very low, even after very late application ofring‐[14C]‐labelled herbicide. The amount of bromoxynil octanoate, together with any metabolite retaining part of the aromatic ring, did not collectively exceed the equivalent of approx. 0.01 parts

ISSN:0031-613X    

DOI:10.1002/ps.2780040510

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY

摘要:

AbstractForty new organofluorine compounds, containing phosphorus, have been synthesised as potential pesticides. The compounds include esters of O,O‐dialkyl phosphoramidic acids of the type (RO)2P(O)NHAr; thioesters ofO,O‐dialkyl thiophosphoramidic acids of the type (RO)2P(S)NHAr; esters ofO,O‐dialkyl phosphonic acid of the type (RO)2P(O)Ar and esters of O,O‐dialkyl thiophosphonic acid (RO)2P(S)OAr. All the compounds have been screened for their insecticidal activity against adult cockroaches (Periplanata americana) and a few show appreciable a

ISSN:0031-613X    

DOI:10.1002/ps.2780040511

出版商:John Wiley&Sons, Ltd    

年代:1973

数据来源: WILEY