bluuebunny/crossref_metadata_2025_split huggingface dataset:
Persistence of 2,4,5‐T in a heavy clay soil
Authors: Walker Allan , Smith Allan E. 
Published: November 2006

AbstractThe persistence of the herbicide 2,4,5‐T was studied at different controlled temperatures and moisture levels in Regina heavy clay. Degradation approximated to first‐order kinetics and the half‐life varied from about 4 days at 35°C and 34% soil moisture to about 60 days at 10°C and 20% soil moisture. The laboratory data were used in conjunction with the appropriate measurements of surface soil temperature and moisture content in the field to simulate the degradation pattern for the herbicide in five separate micro‐plot experiments. Satisfactory agreement with the observed patterns of loss was obtained in two of the experiments but in the other three, the model over‐estimated rates of loss. It is suggested that the reason for this was the difficulty of obtaining a correct measure of soil moisture content to use in the simulation program.
Analysis of polar metabolites of organophosphorus insecticides on an anion‐exchange chromatographic column
Authors: Houx Norbert W. H. , Jongen Wim M. F. , De Vries Anje W. , Welling Wim , Dekker Abraham 
Published: November 2006

AbstractA simple and rapid procedure is described for the qualitative and quantitative analysis of metabolites of malathion and other insecticides. The omission of an extraction at low pH, and mild conditions of anion‐exchange chromatography on QAE‐Sephadex prevent the degradation of a malathion metabolite, S‐(1‐carboxy‐2‐ethoxycarbonyl)‐ethyl O,O‐dimethyl phosphorothioate (malaoxon α‐carboxylic acid), which takes place under strongly acid conditions. Disadvantages of the commonly used fractionation of malathion and malaoxon metabolites based on partitioning are discussed.
Residual sprays for the control of the crazy ant Anoplolepis longipes (Jerd.) in the seychelles
Authors: Haines Ian H. , Haines Jennifer B. 
Published: November 2006

AbstractAttempts to find suitable quick‐acting toxic sprays, for the control of Anoplolepis longipes (Jerd.) in buildings, involved investigations of the toxicity and weathering properties of several insecticide formulations. Their mammalian toxicity was also considered and, particularly for indoor applications, their odour and non‐staining properties. Bendiocarb, gamma‐HCH and chlorpyrifos were particularly effective, killing ants rapidly after minimal contact with spray deposits, but gamma‐HCH and chlorpyrifos weathered better than bendiocarb and were therefore more suitable for outdoor applications.
Potentiation of warfarin toxicity to roof rats (Rattus rattus) by L‐histidine and by vitamin K adsorbers
Authors: Rao Muktha Bai Krishnoji 
Published: November 2006

AbstractThe efficacy of warfarin alone or with various additives was tested against roof rats (Rattus rattus). Warfarin alone at 50 mg kg−1 of bait killed 37% of the roof rats where‐as the additives, L‐histidine (40 mg kg−1 of bait), activated‐clay, charcoal and carbon (10 g kg−1 of bait), tested individually, produced no mortality. However, when warfarin wascombined with each of these additives in turn, only the L‐histidine combination resulted in 100% mortality while the other combinations killed 88, 75 and 63% of the test rats respectively. Further trials of paired comparison tests were carried out in order to evaluate the efficacy of the warfarin/L‐histidine combination under different environmental conditions. All the rats succumbed to this combination in both cage and rattery conditions when there was no alternative food. Mortality decreased to 60% in cage and 70% in rattery when alternative food was provided alongside the poison bait. Rats tended to die more quickly with the L‐histidine combination than with warfarin alone. Field trials also confirmed that this combination was effective in reducing roof rat infestations as shown by the yield of corpses, the post‐poison bait intake and post‐operational surveillance.
Time‐controlled cholinesterase reactions as a means of measuring water‐soluble residues of organophosphorus insecticide spray deposits on plant surfaces
Authors: Uk Solang 
Published: November 2006

AbstractEllman's method of cholinesterase assay which is often used for residue analysis of organophosphorus insecticides has been modified by adding the protein denaturant, sodium dodecyl sulphate, to control the duration of the reaction. In doing so, the reaction time can be standardised to facilitate the measurement in a field laboratory of residues of water‐soluble organophosphates, particularly on plant surfaces that have been subjected to sprays. Thirty samples can be analysed in 1 h by timing each step of the procedure for a series of 30 reaction tubes at 1‐min intervals from the incubation of the enzyme with the insecticide to the final addition of the sodium dodecyl sulphate. Results from a series of aerial spray trials are presented and discussed briefly as an example of a field application of the method.
The effect of gamma‐HCH upon the ultrastructure of the neurohaemal organs on the median nerves of the stick insect (Carausius morosus)
Authors: Osborne Michael P. 
Published: November 2006

AbstractTopical application of gamma‐HCH induced considerable ultrastructural changes and damage in the cellular components of the neurohaemal organs on the median nerves of Carausius morosus. The cytoplasm and nucleoplasm of the glial cells became much more opaque to electrons and shrinkage occurred in the cellular wrappings surrounding the nerve axons. The cytoplasm of the tracheal wall cells and end cells also increased in electron density. Damage to the nervous elements was less evident than to the glial cells but some clumping and increase in electron opacity of the axoplasm took place. Neurosecretory granules could fragment and/or become less opaque to electrons. Some axons that lacked a glial‐cell sheath and contained neurosecretory granules appeared to be disrupted or degenerating. At very high doses there was an apparent reduction in the number of storage granules and an increase in exocytotic profiles in some neurosecretory axons. These results are discussed in relation to the possible modes of action of gamma‐HCH upon the nervous system of insects.
The relative susceptibility of two field collections of Bulinus truncatus (Audouin) to trifenmorph
Authors: Daffalla Ash A‐R. , Duncan John 
Published: November 2006

AbstractChemical control of the intermediate hosts of schistosomiasis, based on copper sulphate, has been practised in the Sudan Gezira since 1956. A continued use of the more recent trifenmorph blanket‐treatments raises the question of eventual resistance to this molluscicide. Two collections of Bulinus truncatus (Audouin), from a treated and an untreated area of the Gezira, have therefore been subjected to laboratory rearing, bioassay and measurement of the rate of uptake of the chemical into the snail. A difference in susceptibility could be shown and this has been tentatively attributed to the rather more marked difference, in penetration rate of the molluscicide, between the two groups of snails.
Toxic effects of surfactants applied to plant roots
Authors: Horowitz Menashe , Givelberg Assia 
Published: November 2006

AbstractSix surfactants used as additives to pesticide sprays, were applied in aqueous solution to the roots of sorghum plants. After a few hours of exposure to the surfactant solution, ions and amino‐acids leaked from the roots into the ambient solution, presumably due to a loss of membrane integrity. After 2‐3 days, the plants wilted and, at high concentrations of surfactants, they died. Toxic effects varied with the surfactant and its concentration, but no clear relationship was found between the physical effect of lowering the surface tension, the release of solutes by the roots, and the injury caused to the plant. The results are of significance because of the proposed use of sewage effluents, known to contain detergents, for irrigation purposes in Israel.
Studies on the degradation of bis(tributyltin) oxide in soil
Authors: Barug Daniel , Vonk Johannes W. 
Published: November 2006

AbstractThe degradation of bis(tri[1‐14C]butyltin) oxide in two soils (1 mg tin kg−1) has been studied under laboratory conditions. Half of the applied compound disappeared from unsterilised silt loam and sandy loam in approximately 15 and 20 weeks, respectively; it disappeared also from the sterilised soils but to a lesser extent. The formation of small amounts of dibutyltin derivatives was established by thin‐layer chromatography both in the unsterilised and sterile soils. The amount of unextractable radioactivity increased with time in the unsterilised and sterile soils. In the unsterilised soils 14C was released as [14C]carbon dioxide in amounts equivalent to 20% of the applied radioactivity for silt loam and 10.7% for sandy loam over a period of 42 weeks. Almost no [14C]carbon dioxide was released from the sterile soils, confirming microbial participation in the degradation of the compound in the unsterilised soils.
Synthesis and screening of a new group of fungicides: 1‐(2‐phenyl‐1,3‐dioxolan‐2‐ylmethyl)‐1,2,4‐triazoles
Authors: van Gestel Jef , Heeres Jan , Janssen Marcel , van Reet Gustaaf 
Published: November 2006

AbstractA series of substituted 1‐(2‐phenyl‐1,3‐dioxolan‐2‐ylmethyl)‐1,2,4‐triazoles has been prepared and evaluated in the glasshouse for fungicidal activity. Compounds with 2,4‐dichloro substitution on the phenyl ring and with a lower alkyl side chain on dioxolane ring were found most promising for the control of powdery mildew gherkins and barley and for the control of bean rust. These compounds were systemically active and some are being developed commercially for various applications.
The pyrethrins and related compounds; Part XXIII:Kinetic control in the formation of pyrethroidal estersb
Authors: Elliott Michael , Janes Norman F. , Khambay Bhupinder P. S. 
Published: November 2006

AbstractThe unequal amounts of the two diastereomers of (RS)‐1‐(3‐phenoxyphenyl)ethyl (RS)‐2‐(4‐chlorophenyl)‐3‐methylbutyrate, obtained from equimolar proportions of the alcohol and acyl chloride under normal conditions, imply stereoselectivity in the reaction. The extent to which this depends on the nature of the α‐substituent for arange of 3‐phenoxybenzyl esters, on the nature of the acid, and on the method of esterification is investigated. Selectivity arises from kinetic, rather than thermodynamic control.
Alkyl aryl ketone oxime O‐ethers: A novel group of pyrethroids
Authors: Bull Michael J. , Davies J. Hugh , Searle Robert J. G. , Henry Arthur C. 
Published: November 2006

AbstractThe alkyl phenyl ketone oxime O‐benzyl ethers are a new group of insecticidal compounds. Although they lack the ester linkage, they resemble the pyrethroids in general, and the esters of 2‐phenylalkanoic acids, in particular fenvalerate, because they show similar physiological effects on isolated nerve preparations and on whole insects; they also show a similar pattern of change of biological activity in response to structural change. The compounds may exist as two geometric isomers, of which only the (E) series shows significant biological activity; this observation appears to have some bearing on the relationship between conformation and activity in the pyrethroid series as a whole.
Carbendazim formulations for the eradication of Dutch elm disease
Authors: Cooke Louise R. , Clifford Derek R. , Gendle Peter , Holgate Margaret E. 
Published: November 2006

AbstractFormulations containing carbendazim (40 or 80 mM) in hydrochloric acid (180 or 320 mM) were pressure‐injected into elms previously inoculated with the fungus Ceratocystis ulmi (the cause of Dutch elm disease) and their performance as eradicants assessed. All formulations caused some damage to foliage but leaves regenerated. Treatment with carbendazim (80 mM) in hydrochloric acid (180 mM) resulted in four out of five trees remaining free from disease, not only immediately after treatment, but also throughout the following season. Injection of acid alone resulted in rapid death of the trees.
A trial to determine the persistence of carbendazim pressure‐injected into elms
Authors: Cooke Louise R. , Clifford Derek R. , Gendle Peter , Holgate Margaret E. 
Published: November 2006

AbstractThe persistence of carbendazim in elm twigs, after pressure‐injection of the commercial formulation ‘Lignasan’ into the trunks, was monitored by bioassay. Initial distribution was poor (38% of twigs contained no detectable fungitoxicant) and after 53 days carbendazim was detected in only 19% of the twigs. In groups of control and injected trees inoculated with Ceratocystis ulmi (the cause of Dutch elm disease) on one of five dates between July and September, disease development was limited and a significant (P=0.05) reduction in symptoms in injected trees was detected only in those inoculated on the first date (2 July 1976). Both the very erratic distribution of fungitoxicant and the restricted disease development, which precluded demonstration of a correlation between fungitoxicant level at inoculation and subsequent symptom expression, were attributed to the effects of the abnormally hot, dry summer in 1976.
Daminozide residues in sweet cherries, and their determination by colorimetric and gas‐liquid chromatographic methods
Authors: Allen John G. 
Published: November 2006

AbstractDaminozide residues in fruit from sweet cherry trees were determined over a period of 4 years as part of an investigation into the effects of growth regulators. Analysis was by the usual colorimetric method. Additionally, for the 2 final years, a gas‐liquid chromatographic method was developed to determine the 1,1‐ dimethylhydrazine produced by hydrolysis of daminozide residues and to confirm the results from the first method.
Uptake of phorate by lettuce
Authors: Suett David L. , Padbury Christine E. 
Published: November 2006

AbstractFollowing experimental and commercial applications to soil of a granular formulalation of phorate (O,O‐diethyl S‐ethylthiomethyl phosphorodithioate), residues in the soil and in lettuce were determined by gas‐liquid chromatography. When applied by the bow‐wave method as a continuous logarithmically‐changing dose ranging from approximately 0.9 to 16.0 kg a.i. ha−1, the proportional rate of oxidation in soil of phorate sulphoxide to phorate sulphone was inversely related to dose. Ten weeks after application, total phorate residues in the soil had declined by about 35% at all dose levels. Residues in mature lettuce, from the 1‐5 kg ha−1 dose‐range, comprised the parent and oxygen analogue sulphoxides and sulphones; the relative proportions of the individual metabolites were independent of dose. Over this dose‐range, total residue concentrations in the crop became proportionally slightly greater with increasing dose. When single doses of 1.1, 2.0 or 2.2 kg a.i. ha−1 were applied at drilling, the total residue concentrations in the lettuce declined from 5 mg kg−1 in seedlings from some treatments to <0.05 mg kg−1 at harvest. In plants raised in peat blocks containing 10 or 20 mg a.i. per block, however, residues in seedlings totalled 45‐47 mg kg−1 and declined to only 0.7 mg kg−1 at harvest. It was concluded that bowwave applications of phorate when field‐sowing lettuce were unlikely to lead to unacceptable residues in the harvested crop, but that residues in lettuce raised in phorate‐treated peat blocks may be unacceptably high.
Delayed toxicity after intravenous administration of bioresmethrin to rats
Authors: Gray Andrew J. , Connors Thomas A. 
Published: November 2006

AbstractCapillary gas‐liquid chromatographic analysis of seven commercial samples of bioresmethrin [5‐benzyl‐3‐furylmethyl (1R)‐trans‐chrysanthemate] demonstrated that each contained toxicologically significant amounts (1‐5%) of the (1R)‐cis‐isomer (cismethrin) as an impurity. Intravenous injection of the labelled compounds to rats indicated that the concentrated solutions of these compounds may precipitate in the blood and subsequently become trapped in the lung. Slow release of the toxic isomer impurity probably accounts for the delay in appearance of symptoms after intravenous administration of impure bioresmethrin. Similarly, higher doses of cismethrin can be tolerated when concentrated solutions are administered intravenously.
Uptake of pesticides from water and soil by earthworms
Authors: Lord Kenneth A. , Briggs Geoffrey G. , Neale Michael C. , Manlove Rosemary 
Published: November 2006

AbstractThe uptake of pesticides by earthworms from aqueous solutions was examined and shown to be a reversible physical process. Measurements of distributions of pesticides between aqueous solutions and worm solids showed that adsorption coefficients were related to octanol‐water distribution coefficients, as are soil‐water distributions. From these relationships it was calculated that concentration factors of stable chemicals in earthworms from soil should be similar, except for polar substances which penetrate poorly, and be determined mainly by the soil organic matter content. Examination of uptake from soils indicated that the calculated concentration factors are unlikely to be achieved because of slow diffusion of chemicals in soils and because of metabolism in the soil or the worm.
New chlorinated juvenile hormone analogues and their biological activity
Authors: Piccardi Paolo , Massardo Pietro , Bettarini Franco , Longoni Angelo 
Published: November 2006

AbstractIn the search for new juvenile hormone analogues (JHAs), a general approach was chosen based on the substitution of the isoprene unit, that carries the epoxy function in the natural hormone JHIII, by 3,3,3‐trichloropropyl, 2,2‐dichlorocyclopropyl‐ methyl, 3,3‐dichloroallyl, or 3‐chloroprop‐2‐ynyl groups. Accordingly, several terpenoid aromatic JHAs were prepared with, or without, oxygen atoms in the aliphatic chain. Structure‐biological activity relationships of the most active compounds toward the yellow mealworm (Tenebrio molitor) and the large cabbage white butterfly (Pieris brassicae) are given. With a view to preparing synthetically accessible analogues, some alkyl phenyl ethers were also made, which were not branched in the aliphatic chain and were related terminally to the most active compounds. They were only moderately active against insects when tested for morphogenetic activity, but exhibited a good field persistence. The occurrence of a moderate acaricidal activity among these analogues prompted the examination of several 1,4‐disubstituted‐phenyl derivatives. The ovicidal effectiveness of these products against a susceptible strain of the two‐spotted spider mite, Tetranychus urticae, was ten or 100 times higher than that of the well known and highly potent JHAs.
Effects of certain herbicides on the oxidative decarboxylation of tryptophan by peroxidase
Authors: Scarponi Luciano , Tafuri Francesco , Perucci Piero 
Published: November 2006

AbstractNon‐enzymic and peroxidase‐catalysed oxidative decarboxylations of tryptophan (TPP) were studied. The in‐vitro rate of enzymic reaction was affected by various herbicides at low concentrations (10−5−10−4M): dinoseb, 2,4‐D, dichlobenil and benazolin acted as inhibitors; on the other hand, chlorpropham, bromacil, diphenamid and 4‐ethylamino‐6‐isopropylamino‐1,3,5‐triazin‐2‐ol (hydroxyatrazine) were stimulatory. The results of in‐vivo experiments showed that chlorpropham and 2,4‐D changed the activity of peroxidase from Brassica germinated seeds in vivo, as they do in vttro. Determinations of consumed TPP were carried out either by spectro‐photometry or by chromatography.
The photolysis of quinomethionate in benzene solution
Authors: Clark Terence , Thomas Loeffler R. S. 
Published: November 2006

AbstractThe photolysis of quinomethionate in benzene solution was found to result in complete cleavage of the dithiole ring with loss of both sulphur atoms. Products isolated and identified were those arising from the reaction of intermediate radicals with oxygen and with the solvent. They were identified, by gas chromatography‐mass spectrometry and by comparison with authentic samples synthesised by known methods, as 6‐methyl‐1,2,3,4‐tetrahydroquinoxaline‐2,3‐dione and 6‐ and 7‐methyl‐3‐phenyl‐1,2‐ dihydroquinoxalin‐2‐one. A mechanism that accounts for the formation of these products is presented.
Hydrolysis of cyanazine and related diaminochloro‐1,3,5‐ triazines. Part II: hydrolysis in sulphuric acid solutions
Authors: Terence Grayson B. 
Published: November 2006

AbstractHydrolysis of cyanazine in sulphuric acid solutions involves primary attack at the nitrile group to give first the corresponding amide and then the carboxylic acid followed subsequently by displacement of the chlorine atom. Comparison of the respective reaction rates showed that, in sulphuric acid solutions (at concentrations around 0.5M) at 25°C, the rate of this attack at the nitrile group is approximately ten times faster than at the chlorine atom. The kinetic data indicate that in these moderately acid solutions the mechanism of cyanazine hydrolysis corresponds to an A‐2 reaction involving prior protonation of the nitrile group followed by rate determining nucleophilic attack by water. However, at higher acidities, the rates decelerate which leads both to diversion from the Zucker‐Hammett postulate for simple A‐2 reactions and to undue curvature in the Bunnett or Bunnett‐Olsen linear free‐energy plots, so that with the present data such a conclusion cannot be extended to the reaction in solutions of acidity higher than 0.5M. Removal of the chlorine atom attached to the 1,3,5‐triazine ring in atrazine was also found to be an A‐2 reaction in moderately acid solutions, but at higher acidities ([H+]>2M), there is an acceleration in the rate. It is suggested that this is a consequence of diprotonation of the diamino‐1,3,5‐triazine molecule.
Pesticide breakdown by soil enzymes
Authors: Burns Richard G. , Edwards Jennifer A. 
Published: November 2006

AbstractA proportion of natural substrate decay in soil is effected by extracellular enzymes tenaciously associated with the humic colloids. This indigenous catalytic component (‘accumulated’ enzyme) may also be involved in pesticide breakdown, particularly the organophosphorus compounds and the acylanilides, and this possibility is considered here. Additionally, guide‐lines for detecting and then confirming the presence of accumulated pesticide‐degrading enzymes are suggested.
The pyrethrins and related compounds; Part XXIV: synthesis, 13C‐nuclear magnetic resonance spectra and insecticidal activity of cycloalkyl analogues of fenvalerate
Authors: Elliott Michael , Farnham Andrew W. , Janes Norman F. , Johnson Diana M. , Pulman David A. 
Published: November 2006

AbstractClose isosteres of fenvalerate [(RS)‐α‐cyano‐3‐phenoxybenzyl (RS)‐2‐(4‐chlorophenyl)‐3‐methylbutyrate], in which cyclopropyl groups replace isopropyl have insecticidal activity close to or greater than the parent compounds, and diminished intravenous toxicity to rats. A direct toxicological relationship of these compounds to fenvalerate itself and to chrysanthemate esters is indicated by the consistently greater activity of esters from one of an enantiomeric pair of acids. Other esters with larger alkyl or cycloalkyl groups, or spiropentane analogues of chrysanthemates are less active insecticides. 13C‐Nuclear magnetic resonance spectra suggest that in the α‐cyanobenzyl esters there is an intramolecular through‐space interaction in solution. The relationships between the chemical structures of the compounds synthesised and their relative activities to different insect species and toxicity to rats are discussed.