摘要:

AbstractThe biorational design of new miticides requires an understanding of the biochemistry and physiology of mites. This review considers the interaction and impact of existing miticides with the cuticle, nervous system, growth and development, metabolism, feeding and behaviour and assesses the potential of these as possible targets for miticide development. Considering the sites of action of some of the major miticides, GABAergic and octopaminergic transmission, and oxidative phosphorylation are attractive targets for further miticide development.

ISSN:0031-613X    

DOI:10.1002/ps.2780400202

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe pure individual stereoisomers of endosulfan, alpha‐endosulfan and beta‐endosulfan, were applied as emulsifiable concentrates to chickpea crop at the rate of 175 g a.i. ha −1 and 50 g a.i. ha −1, respectively. The dissipation rate of these isomers revealed that alpha‐endosulfan interconverted to beta‐endosulfan in minor quantities, while it was converted into endosulfan sulfate on chickpea leaves in significant amounts. On application, beta‐endosulfan was converted to endosulfan sulfate and alpha‐endosulfan in relatively smaller amounts. The study indicates that the beta stereoisomer of endosulfan is more persistent because it is resistant to interconversion and m

ISSN:0031-613X    

DOI:10.1002/ps.2780400203

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractIsoxazole‐substituted 1‐aminoethyl‐ and 1‐hydroxyethyiphosphonates were synthesized by a multi‐step procedure and were screened for herbicidal activity against Lepidium sativum L. and Cucumis sativus L. All the synthesized compounds exhibited notable herbicidal

ISSN:0031-613X    

DOI:10.1002/ps.2780400204

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe influence of allosamidin and its diastereoisomer isoallosamidin on chitinase activity from an insect cell line of Chironomus tentans, the crustacean Artemia salina and the bacterium Streptomyces griseus was studied. The rank order of susceptibility of chitinase activity to both inhibitors was found to be: insects »crustaceans« fungi, although isoallosamidin is about 600‐fold (insect) or 400‐fold (crustacea) less active than allosamidin and does not inhibit chitinase from Streptomyces at all. The complete and exclusive inhibition of N‐acetyl‐β‐D‐glucosaminidase by an acetylgluconolactone‐derivative and chitinase activity by allosamidin indicates that both enzymes can be determined separately in crude extracts, (containing both enzymes), with the substrates 4‐methylumbelliferyl‐N‐acetylglucosaminide or 4‐methylumbelliferyl

ISSN:0031-613X    

DOI:10.1002/ps.2780400205

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractSoxhlet extraction with hexane + acetone (1 + 1 by volume) was used for the extraction of organochlorine pesticide residues from river sediments, followed by Florisil column chromatography clean‐up and determination by gas chromatography with an electron‐capture detector. Average recoveries exceeding 90 % were obtained using this technique. Organochlorine pesticide residue levels in sediment samples from two major rivers flowing through predominantly rice‐growing areas were determined by this method. Relatively high residue levels of organochlorine pesticides such as HCH, heptachlor and endosulfan were found in the sedi

ISSN:0031-613X    

DOI:10.1002/ps.2780400206

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe dissipation of MCPA and cyanazine in smooth bromebrass (Bromus inermis Leyss.), Russian wild ryegrass (Elymus junceus Ficsch.) and intermediate wheatgrass (Agropyron intermedium) (Host) Beauv.) grown at three sites in western Canada was monitored for an eight‐week period following post‐emergence application of the herbicides as a mixture at 0.56 + 0.28 kg ha −1. The grasses were in the two‐ to six‐leaf stage at the time of application. MCPA, as its methyl ester, was detected using electrolytic conductivity detection whereas N‐specific alkali‐ionization detection was used for cyanazine. Foliar MCPA residues decreased more rapidly than those of cyanazine. At 56 days after application, MCPA residues were non‐detectable in all three grass species at all sites. Corresponding residues of cyanazine were of the order of the limit of quantification (0.02 m

ISSN:0031-613X    

DOI:10.1002/ps.2780400207

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractThe phenylpyrrole fungicide fenpiclonil accumulates to high levels in mycelium of Fusarium sulphureum and artificial liposomes. The accumulation is a result of a physicochemical distribution of the fungicide over lipid‐like material of the mycelium and the medium. Accumulation is reversible, as the fungicide can easily be removed from the mycelium by washing with water. Fenpiclonil is not metabolized by the fungus during incubation for 24 h. The fungicide affects neither membrane fluidity in artificial liposomes nor amino acid accumulation in bacterial vesicles. Thus, accumulation of the fungicide does not seem to affect the functioning of membranes.Fenpiclonil induces the accumulation of the membrane‐potential probe tetra‐phenylphosphonium bromide by F. sulphureum. Since accumulation of this probe probably reflects the cumulative potential over all cell membranes, the increased accumulation is more likely a result of changes of potentials over membranes of intracellular organelles rather than plasma membrane hyperpolarization. Hence, the previously described effects of fenpiclonil on amino acid and saccharide uptake cannot be explained by plasma membrane hyperpolariz

ISSN:0031-613X    

DOI:10.1002/ps.2780400208

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractA series of new 1,3, 4‐oxa(thia)diazol‐2(3H)‐ones were synthesized and tested as acaricides. High activities against eggs of Tetranychus urticae (Koch) were found for derivatives bearing an ortho‐halo‐substituted phenyl group in position 3, and a benzyl group para‐substituted by a branched C3‐C6alkoxy group in position 5 of the hetero‐ring. The best compounds attained the miticidal potency

ISSN:0031-613X    

DOI:10.1002/ps.2780400209

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractMethiocarb, a broad‐spectrum carbamate insecticide, has shown efficacy in repelling birds from a variety of crops, especially fruit. To evaluate the hazards posed to wildlife, we reviewed laboratory studies of methiocarb toxicity and repeilency to birds and mammals and field studies of methiocarb treatments to fruit and sweet corn. Calculations revealed that birds encountering typical maximum residue levels found in treated crops would have to eat extremely large amounts of treated food to die and would in almost all cases be repelled or immobilized long before a lethal dose could be ingested.Results from feeding tests in laboratories support these calculations, as do the findings from 33 field studies in 28 locations. In spite of extensive searches and observations, only 14 dead birds were found in treated fields. Based on estimates from 26 studies, treated plantings averaged 15% loss of fruit to birds compared with 36% for nearby untreated plantings. We conclude that methiocarb, applied to fruit crops at 1–7 kg a.i. ha −1, will not adversely affect

ISSN:0031-613X    

DOI:10.1002/ps.2780400210

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY

摘要:

AbstractPrediction of the fate of pesticides in soil is of interest from an environmental (pollution) as well as an agricultural (efficacy, carryover) viewpoint. Two environmental parameters that control microbial degradation of pesticides in soil are moisture and temperature. This study was designed to quantify the impact of soil water content and temperature on microbial degradation rates of the insecticide carbofuran (2, 3‐dihydro‐2, 2‐dimethylbenzofuran‐7‐yl methyl‐carbamate). Carbofuran degradation was determined by monitoring the [ 14 C] carbondioxide production from soils amended with [carbonyl‐ 14 C]carbofuran. Soils were incubated at seven soil‐water tensions over the range of 0–03 to 1–5 MPa, and at five temperatures (10°C to 30°C). The sigmoidal degradation kinetics observed from these incubations were modeled using a general saturation model. For the moisture experiments, maximum rate of hydrolysis and half‐life (DT50) were accurately modeled by an exponential relationship. The response of carbofuran degradation to temperature was also well described by an exponential relationship, from which it was estimated that the Q10associated with the maximum rate was 1.68, and

ISSN:0031-613X    

DOI:10.1002/ps.2780400211

出版商:John Wiley&Sons, Ltd    

年代:1994

数据来源: WILEY