摘要:

AbstractA novel compound, 1‐(3‐trifluoromethylphenyl)‐5‐phenoxy‐1,2,3,4‐tetrazole (WL 110547) is a pre‐emergence bleaching herbicide with selectivities in certain crops. These selectivities and the weed‐control spectrum are derived, in part, from features which influence the uptake of WL 110547 into sensitive tissue. WL 110547 is strongly adsorbed to soil with measuredKocvalues in the range 1500‐2500 and, following application, is confined to the surface layers of soil, especially when the organic matter content is high. Some plant species have anatomical features which protect their developing leaf tissue from contact with the soil during emergence and thus escape direct contact with these treated layers. Furthermore, some of these plants are deeply rooted and thus there is little opportunity for sufficient uptake of WL 110547 to cause a phytotoxic effect.However some weeds, especially annual dicotyledons, germinate only from shallow depths and, during emergence, their cotyledons or leaves are in contact with the soil. In soils treated with WL 110547 they can thus absorb phytotoxic concentrations of herbicide directly into their cotyledons or leaves. Additional uptake may also occur through roots near the surface and allow WL 110547 to be translocated via the transpiration stream to the site of action in cotyledons and leaves and enhance phytotoxicity.Knowledge of the features controlling uptake, combined with a knowledge of intrinsic susceptibility, have allowed an understanding of the spectrum of weed control and the selectivities betwee

ISSN:0031-613X    

DOI:10.1002/ps.2780280202

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractPre‐emergence applications of the novel tetrazole herbicide WL 110547 control a number of economically important grass and broad‐leaved weed species in small grain cereals. To assess the influence of plant and environmental factors on the biological performance of WL 110547, a series of tests were carried out under controlled conditions and, where appropriate, comparisons were made with field observations.When presented with the maximum opportunity for compound uptake in the absence of soil, differences in the degree of susceptibility to WL 110547 were observed amongst both monocotyledonous and dicotyledonous species, although the latter group generally showed higher levels of phytotoxicity. This species susceptibility to WL 110547 was unaffected by temperature.Increasing the sowing depth in soil decreased the level of effect of WL 110547 on a number of monocotyledonous species, although small‐seeded species (e.g. blackgrass, annual meadow grass), emerging from deep in the soil profile, subsequently developed levels of phytotoxicity comparable to, or even greater than, shallow‐planted seedlings. This was attributed to less vigorous seedlings, emerging from depth, that were unable to regenerate new tissue and grow away from a treated soil layer. Reduced growth rates of wild oat, blackgrass and speedwell, induced by low temperatures, also increased the phytotoxicity of WL 110547. Furthermore, applications of WL 110547 during seedling emergence maximised herbicide effect, as did seedling emergence through moist rather than dry soil.The results are discussed in relation to the mobility of the herbicide in soil, the mode of action of WL 110547, its availability to the plant and the duration of contact between emerging shoot and treated soi

ISSN:0031-613X    

DOI:10.1002/ps.2780280203

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractSix new pesticide metal complexes were synthesised, characterised and evaluated for controlled release by chemical and bioassay methods. Chemical assay and bioassay data demonstrate the increased persistence and increased shelf life of the pesticides upon complexation.

ISSN:0031-613X    

DOI:10.1002/ps.2780280204

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractDrawing on the experience gained in the management of resistance inHeliothis armigerain Australia, the successive stages of designing, setting up and monitoring an insecticide resistance management (I R M) programme are discussed, along with the problems that may have to be overcome in order to achieve success. While individual strategies will inevitably differ, the Australian experience should give valuable information for the setting up of IRM programmes worldwide.

ISSN:0031-613X    

DOI:10.1002/ps.2780280205

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractThe stability of some diluted emulsifiable concentrate formulations in clear liquid fertilizers, as affected by the nature and concentration of the salt solutions, was checked by a static test. The time‐induced changes in the concentration of the dispersed phase were estimated by visual observations and turbidity measurements. For each formulation a specific relationship between the electrical conductivity of all the fertilizer solutions and the emulsion stability was found. This was valid for a pH range between 4.6–6.3; in alkaline conditions the emulsion stability was relatively lower. A critical electrical conductivity range, above which irreversible destabilization occurred, was observed for each formulation: 100‐120 dS m−1for fenamiphos, 60‐70 dS m−1for metolachlor, 30‐50 dS m−1for chlorpyrifos, and about 45 dS m−1for S‐ethyl dipropylthiocarbamate (EPTC).The correlation observed between the emulsion stability and the electrical conductivity could be used in a simple and rapid qualitative test to estimate the physical compatibility between emulsifiable concentrate formulations and

ISSN:0031-613X    

DOI:10.1002/ps.2780280206

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractA capillary column gas chromatographic method is described for the determination of tau‐fluvalinate in honey samples. The method involves solid phase extraction of the sample with two RP C‐8 cartridges in series, purification of the extract, if necessary, on a silica cartridge, and detection of the active ingredient with an electron capture detector. The method is rapid and overcomes the problem of emulsion formation in liquid/liquid partition often found in traditional systems. The detection limit in actual samples is 0.01 mg kg−1and mean recoveries for fortified samples prepared with or without clean‐up are greater t

ISSN:0031-613X    

DOI:10.1002/ps.2780280207

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractA CIPAC/AOAC test with tomato plants is used to specify the volatility ratings of herbicide ester formulations. This work compares the tomato plant test with an alternative chemical one. The concentrations of esters and the effective molecular weight and density of each formulation were used with the ester vapour pressures to calculate its herbicide vapour pressure as complete, and evaporated formulations. The range was from 28.8 mPa (at 257deg;C) for a mixture of 2,4–D esters to 0–07 mPa (at 25°C) for a 2,4,5–T‐(iso‐octyl) formulation, as complete formulations, and 35‐5 and 0–16 mPa (at 25°C) as evaporated ones. A value of 0–6 mPa (at 25°C) was selected on the basis of the tomato plant test as the cut‐off area for low‐volatile esters and is recommended to be included in specifications for herbicide esters. Formulations with a herbicide vapour pressure above 3.3 mPa (at 25°C) are high‐volatile ones according to the tomato plant test, while between 0–6–3.3 mPa (at 25°C) is a borderline region where the test gives mixed results. Levels of 2,4–D‐ethyl and methyl were added to pure 2–ethylhexyl esters of 2,4–D and a 2,4,5–T‐(iso‐octyl) formulation to find what level of contamination would change the rating of these esters from low to high volatile. Formulations of 2,4–D‐(iso‐octyl) should not contain more than 11 g litre−12,4–D as methyl ester or 2.0 g litre−12,4–D as ethyl ester. Formulations of 2,4,5–T‐(iso‐octyl) should not contain more than 26 g

ISSN:0031-613X    

DOI:10.1002/ps.2780280208

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractRecombinant DNA technology has enabled the expression of a large number of eukaryotic genesin vitro.There has been growing interest in recent years in the development of baculovirus expression vectors as an easily manipulated gene expression system. Both virus and insect cell culture are relatively easy to handle, and biologically active proteins have been produced abundantly from a variety of eukaryotic, prokaryotic and viral genes. This review describes the molecular biology of baculoviruses and some of the current applications of the baculovirus expression system in insect cells. Specific emphasis is placed on those features relevant to the use of this system in pesticide research.

ISSN:0031-613X    

DOI:10.1002/ps.2780280209

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

摘要:

AbstractThe following are extended abstracts of papers presented at a meeting of the Pesticides Group held on 1 March 1989 at the Society of Chemical Industry, 14 Belgrave Square, London SWIX 8PS. The papers published here are entirely the responsibility of the authors and do not reflect the views of the Editorial Board of Pesticide Science.

ISSN:0031-613X    

DOI:10.1002/ps.2780280210

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY

ISSN:0031-613X    

DOI:10.1002/ps.2780280211

出版商:John Wiley&Sons, Ltd    

年代:1990

数据来源: WILEY