摘要:

AbstractThe uptake and movement of a chemical into a wheat leaf has been simulated in a 5‐compartment model. The compound is considered to be applied to the leaf as discrete droplets of solution, from which water evaporates at a uniform rate. Solute diffuses from the droplets through the plant cuticle into the epidermal cell wall, and from there either into and out of the cytoplasm and vacuole of the mesophyll cells or along cell walls to the xylem. Once in the xylem it is carried in the transpiration stream towards the tip of the leaf.Accurate values for the parameters required by the model have not yet been measured, but the model simulates in a qualitative manner the movement pattern observed for 1‐methyl‐2‐pyridone. The results presented focus attention on the possible importance of membrane permeability in determining the phytotoxicity of xylem mobile pes

ISSN:0031-613X    

DOI:10.1002/ps.2780050402

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractA simple, quick and reliable method is described for the colorimetric estimation of residues of eight carbamate insecticides. The method is applicable to carbamates which on hydrolysis yield phenols with free para‐positions suitable for coupling with a diazo reagent to yield coloured solutions. Optimum conditions for the development and measurement of the colour are described. Analytical data including graphs and some results from mud‐bricks and cloth are presented to show the wide applicability of the met

ISSN:0031-613X    

DOI:10.1002/ps.2780050403

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe process of volatilisation of solvents and active ingredients from solid and liquid formulated products has been investigated. Plotting the amount of active ingredient volatilised from a carrier against the square root of time resulted in a linear curve. A simple method of determining the volatility of an active ingredient from layers of its formulated product is also described.

ISSN:0031-613X    

DOI:10.1002/ps.2780050404

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractData were collected that are needed to simulate soil fumigation with metham‐sodium with computation models. The rate of conversion of metham‐sodium into methyl isothiocyanate was dependent on temperature and soil type, and conversion was usually completed within a few hours. In comparison with dichloropropene, there was a higher water/gas distribution ratio and thus a slower vapour diffusion. Adsorption from the water phase onto the solid phase was weaker. The first‐order rate equation described the decomposition of methyl isothiocyanate and the half‐lives varied from a few days to a few weeks according to temperature and so

ISSN:0031-613X    

DOI:10.1002/ps.2780050405

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractSoil fumigation with metham‐sodium in the field was studied in detail by characterising soil and climatic conditions, and by measuring concentrations of methyl isothiocyanate. The effectiveness of two dosages in two contrasting soil profiles was compared on the basis of computed concentration‐time products for methyl isothiocyanate in the water phase. Under wet conditions, the vapour diffusion of methyl isothiocyanate was very slow and resulted in an irregular distribution in the soil. Showers further decreased effectiveness in the upper part of the soil. A dried top layer was unfavourable for the concentration‐time product near to the surface. Diffusion of methyl isothiocyanate to depths greater than about 30 cm was very

ISSN:0031-613X    

DOI:10.1002/ps.2780050406

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractIn field trials, loamy soils were fumigated by injecting dichloropropene and metham‐sodium with a horizontal‐blade injector. Concentrations ofcis‐andtrans‐1,3‐dichloropropene, and of methyl isothiocyanate were measured. The influence of different methods of tillage on fumigation effectiveness was compared by computing concentration‐time products at the various depths in the soil. With a fine‐structured top layer, there was no clear beneficial effect of shallow or deep rotary tillage before injection. If a dense top layer was not rotary‐tilled beforehand, deep and wide cracks were formed during injection. Shallow or deep rotary tillage both left loose cereal stubble mixed in the surface layer, which was difficult to finish off. Concentration‐time products could be substantially increased by finishing off the soil surface bette

ISSN:0031-613X    

DOI:10.1002/ps.2780050407

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe herbicide benzoylprop‐ethyl [SUFFIX,aethyl (±)‐2‐(N‐benzoyl‐N‐3,4‐di‐chloroanilino) propionate] has been applied in a radiolabelled form to spring wheat and winter wheat growing both indoors and outdoors. During the application the compound also fell onto the soil. The plants and corresponding soils were examined at harvest at 71‐98 days from treatment.Conversion of the herbicide occurred in plants and soil predominantly by a hydrolytic reaction to form benzoylpropbfollowed in plants by its conjugation with sugars. Small amounts ofN‐benzoyl‐3,4‐dichloroaniline and benzoic acid were also detected in plants. There was no evidence for the presence of 3,4‐dichloroaniline in the crops or soils nor was there evidence for 3,4,3′,4′‐tetra‐chloroazobenzene which has been implicated as a degradation product of some 3,4‐dichloroaniline herbicides in soils.Residues on plants were greatest in the straw and consisted mainly of benzoylprop‐ethyl and benzoylprop in free and conjugated forms. There was no evidence for appreciable movement of the compound within the plant from the treated foliage. Residues were particularly low in the grain and were not detected in the crop grown outdoors (limit of detectability 0.01 mg/kg). Residues in the soils were mainly in the 0‐7.5 cm layer and there

ISSN:0031-613X    

DOI:10.1002/ps.2780050408

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe herbicide benzoylprop‐ethyl (SUFFIX,aethyl (±)‐2‐(N‐benzoyl‐3,4‐dichloro‐anilino) propionate) is applied post‐emergence for the control of wild oats(Avenaspp.) in wheat. During application some falls onto the soil and in the present work the possible uptake of residues from the soil, particularly by rotation crops has been studied using radioisotope techniques under indoor and outdoor conditions.Soil application at 1 kg/ha gave lower residues in wheat in the year of application than were found in previous studies using overall foliar‐soil application. In the radiochemical experiments soil residues did persist into the following year, but residues in potatoes and wheat grown in these soils, although generally below the limit of determination (0.005 mg/kg), were occasionally just above this level (0.006 mg/kg).On the results of the present work, residues in rotational crops from soils treated in the previous year are unlikely to reach the limits of normal analyt

ISSN:0031-613X    

DOI:10.1002/ps.2780050409

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractThe degradation of [14C] benzoyl prop ethyl (SUFFIX,aethylN‐benzoyl‐N‐(3,4‐dichlorophenyl)‐2‐aminopropionate) in four soils has been studied under laboratory conditions.The major degradation product of benzoylprop ethyl at up to 4 months after treatment was its corresponding carboxylic acid (II). On further storage this compound became firmly bound to soil before it underwent a slow debenzoylation process which led to the formation of a number of products includingN‐3,4‐dichlorophenylalanine (IV), benzoic acid, 3,4‐dichloroaniline (DCA), which was mainly present complexed with humic acids, and other polar products. Although these polar products were not identified, they were probably degradation products of DCA, since they were also formed when DCA was added to soil. No 3,3′,4,4′‐tetrachloroazobenzene (TCAB) was detected in any of the soils at limits of detectability ranging from 0.01‐0.001 parts/million.SinceN‐3,4‐dichlorophenylalanine (IV) and 3,4‐dichloroaniline were transient degradation products of benzoylprop ethyl, the metabolism in soil of radiolabelled samples of these compounds was also studied.In these laboratory experiments the persistence of the herbicide increased as the organic matter content of the soil increased and the time for depletion of half of the applied benzoylprop ethyl varied from 1 week in sandy loam and clay loam s

ISSN:0031-613X    

DOI:10.1002/ps.2780050410

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY

摘要:

AbstractA review of the analytical methods for the detection and determination of residues of systemic fungicides in foodstuffs is presented.

ISSN:0031-613X    

DOI:10.1002/ps.2780050411

出版商:John Wiley&Sons, Ltd    

年代:1974

数据来源: WILEY