bluuebunny/crossref_metadata_2025_split huggingface dataset:
New pesticide metal complexes for controlled release
Authors: Prasad B. Prabhu , Kantam M. Lakshmi , Choudary B. M. , Sukumar K. , Satyanarayana K. 
Published: November 2006

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.
Stability of emulsifiable concentrate pesticide formulations in liquid fertilizers
Authors: Saltzman Sarina , Brates Nelly 
Published: November 2006

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−1 for fenamiphos, 60‐70 dS m−1 for metolachlor, 30‐50 dS m−1 for chlorpyrifos, and about 45 dS m−1 for 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 liquid fertilizers.
Genetic analysis and effect of synergists on diazinon resistance in the bulb mite, rhizoglyphus rohini claparède (acari:Acaridae)
Authors: Chen Jeng‐Shong 
Published: November 2006

AbstractA genetic analysis revealed that the resistance to diazinon of the bulb mite, Rhizoglyphus robini Claparède. lacked sex linkage, and was based on the operation of a dominant allele. Synergism of diazinon by eight inhibitors of detoxifying enzymes in susceptible and resistant strains of the bulb mite was determined. Esterases were shown to play an important role in detoxification against diazinon. S.S.S‐tributyl phosphorotrithioate, an esterase inhibitor, was the only synergist which obviously synergized diazinon. The others, including the inhibitors of glutathione‐S‐transferases, carboxylesterase and mixed function oxidases, showed obscure or even antagonistic effect.
Organosilane insecticides. Part II: Chemistry and structure—activity relationships
Authors: Sieburth Scott McN. , Langevine Charles N. , Dardaris David M. 
Published: November 2006

AbstractSilicon effectively substitutes for quaternary carbon in etofenpr ox‐type insecticides; the resulting dimethyl‐4‐ethoxyphenyl‐3‐(4‐fluoro‐3‐phenoxyphenyl)propylsilane is a broad‐spectrum insecticide with extremely low toxicity to fish. Four regions of this new silane insecticide have been systematically altered. The methyl groups on silicon appear to be critical for activity. Replacement of the fluorine with hydrogen results in a substantial loss of activity. The aromatic rings of the phenoxyphenyl fragment are best tethered by oxygen or carbonyl, the methylene and nitrogen analogs being of very low toxicity to the test species. The activity ranking of the methylene and carbonyl tethers is opposite to that found for ester pyrethroids. The relationship of insecticidal activity to the aromatic substituent para to the silicon atom has been found to correlate with the molar refractivity of the substituent. Replacement of a tetra‐substituted carbon atom with a silicon atom can simplify construction of test compounds and thus be advantageously used in the exploration of structure—activity relationships. A novel method for preparing allylbenzenes from aromatic aldehydes was also developed.
Spreading of spray mixtures on leaf surfaces: I. relative effectiveness of various physico‐chemical predictors
Authors: Abbott Henry A. , Van Dyk Louis P. , Grobbelaar Nathanaël 
Published: November 2006

AbstractSurface tension, contact angles and critical micelle concentration were not effective as practical predictors of spreading. Contact angles could not quantify spreading past the point where the angles became zero, although differences could be discerned by eye. Measurement of diameter of spread allowed quantification of these differences. Hansen parameters, used instead of surface tension, underlined the importance of hydrogen‐bonding and charge effects, but could not explain all the observed phenomena. The results emphasise the complexity of spreading on leaf surfaces, and problems experienced with several approaches encountered in the literature are discussed.
Spreading of spray mixtures on leaf surfaces: II. cohesive interaction parameters as predictors of spreading and the effect of molar volume and roughness on spreading
Authors: Abbott Henry A. , Van Dyk Louis P. , Grobbelaar Nathanaël 
Published: November 2006

AbstractPartial cohesive interaction parameters as predictors of the spreading of spray mixtures were investigated. Multiple linear regression of the inverse of the area of spread, 1/A, for leaf surfaces on the partial cohesive interaction parameters of pure liquids gave a good fit (r2 > 0–90) on virtually all tested surfaces. The coefficients obtained from the regression analysis could be used to describe the spreading properties of each surface uniquely. Regression of 1/Afor an unknown liquid on the coefficients of known surfaces could, conversely, be used to obtain the cohesive interaction parameters of the unknown liquid. A linear relationship was observed between the calculated energy of adsorption and the inverse of the area of spread. An increase in molar volume caused a decrease in the slope of the regression line and an increase in roughness caused a similar, but more pronounced, decrease.
Fungitoxicity of 6H‐pyrazolo[3,4‐c][l,2,5]thiadiazine‐2,2‐dioxides
Authors: Vicentini Chiara B. , Brandolini Vincenzo , Poli Tiziana , Veronese Augusto C. , Guarneri Mario , Giori Paolo 
Published: November 2006

AbstractA base‐promoted cyclisation of 4‐nitroso‐5‐benzylsulphonamidopyrazoles (VII) afforded 6H‐pyrazolo[3,4‐c][1,2,5]thiadiazine‐2,2‐dioxides (VIII). They were testedin vitrofor antifungal activity against a series of phytopathogenic fungi of different taxonomic classes. Five of the compounds had noteworthy activity; in particular 6H‐3‐phenyl‐5‐methyl‐7–(3,4‐dichlorophenyl) pyrazolo[3,4‐c][1,2,5]thiadiazine‐2,2‐dioxide (VIIIc) at the concentration of 200 mg litre−1completely inhibited the growth ofPythium ultimum, Corticium solaniandSclerotinia minor.
Regulatory pressures on pesticide formulations
Authors: Thomas Barry 
Published: November 2006

AbstractA greater public, political and regulatory awareness of chemicals in general, and in particular of their environmental behaviour, has led to increased attention being given to the so called ‘inert’ ingredients of pesticide formulations. Specific controls of these ‘inerts’ have been developed and introduced in the USA whilst in Europe the approach at national and Community level has been more broad‐based. These legislative controls and their associated influence on the labelling and data requirements for pesticide formulations are discussed. The positive move towards ‘safer’ formulations is to be welcomed and will hopefully not lose momentum in the light of increasing regulatory pressure on the individual constituents.
Influence of solid/liquid ratio on the experimental frror of sorption coefficients in pesticide/soil systems
Authors: Boesten Jos J. T. I. 
Published: November 2006

AbstractThe influence of the solid/liquid ratio on the experimental error in the sorption coefficient in pesticide/soil systems was assessed by theoretical analysis. It was assumed that the sorption coefficient is derived from the measured decrease in concentration in the liquid phase of a soil suspension. A first analysis based on systematic errors in the concentration in the liquid phase showed that the relative error in the sorption coefficient is controlled by the product of the solid/liquid ratio and the sorption coefficient (a dimensionless quantity). If this quantity tends to zero, the relative error tends to infinity. A second analysis, based on random errors in the concentration in the liquid phase, gave a similar result. To minimize experimental errors the solid/liquid ratio should be taken as large as possible unless the equilibrium concentration becomes too low to be measured accurately.
The use of pharmacokinetic models in the development and evaluation of site‐specific drug delivery systems
Authors: Aarons Leon , Boddy Alan 
Published: November 2006

AbstractThe influence of the pharmacokinetics of drug‐carrier conjugates and free drug and of the pharmacodynamics of therapeutic and toxic responses on the potential for successful targeting is discussed. A simple physiologically based compartmental model is used to explore the potential of drug‐targeted systems versus conventional administration. The major kinetic factors affecting the therapeutic advantage of targeted systems are the blood flow to the target site, the systemic clearance of free drug and the selectivity of release of drug from its carrier. A model independent analysis based on linear systems theory using a recirculating model of drug disposition is also described.
Effect of seed treatment in preventing transmission of dwarf bunt of winter wheat to new areas
Authors: Mathre Don E. , Johnston Robert H. , Grey William E. 
Published: November 2006

AbstractThe effectiveness of various fungicide formulations containing carboxin and thiabendazole in eradicating teliospores of Tilletia controversa (dwarf bunt) from winter wheat seed was evaluated in the laboratory and the field. In the laboratory tests, the viability of teliospores washed from treated infested seed was greatly reduced as compared to the viability of teliospores washed from untreated infested seed, suggesting that carboxin and thiabendazole were primarily fungicidal. Field tests in two different years were established to determine if teliospores from treated infested seed could infect nearby untreated noninfested seed. Formulations containing carboxin were highly effective in reducing infection of healthy seed. No dwarf bunt infected plants developed in either year from seed treated with ‘Vitaflo 250’. Furthermore, seedborne common bunt caused by Tilletia foetida was nearly eradicated by carboxin‐containing formulations in one field test. Carboxin treatment of winter wheat seed infested with dwarf bunt teliospores will greatly reduce the danger of introducing this pathogen into new areas.
Invertebrate pharmacological assay of novel, potent glutamate receptor antagonists: Acylated spermines
Authors: Blagbrough Ian S. , Bruce Mary , Bycroft Barrie W. , Mather Alan J. , Usherwood Peter N. R. 
Published: November 2006

AbstractSynthetic analogues of arthropod polyamine‐containing toxins have been investigated for antagonism of the quisqualate‐sensitive L‐glutamate receptor (quis‐GluR) of locust muscle. Block of the cation‐selective channel gated by quis‐GluR was demonstrated for N‐(4‐hydroxyphenylpropanoyl)‐and N‐(4‐hydroxyphenylacetyl)‐spermine at significantly lower concentrations than that for spermine.
Volatile analogues of penconazole and their activity against the take‐all fungus, Gaeumannomyces graminis var. tritici
Authors: Chamberlain Keith , Bateman Geoffrey L. , Nicholls Peter H. 
Published: November 2006

AbstractEight new sterol biosynthesis‐inhibiting fungicides, structurally related to penconazole and having vapour pressures up to 118 mPa, were synthesised. Their toxicities to the cereal take‐all fungus, Gaeumannomyces graminis var. tritici, on agar were measured; intrinsic activities were measured after incorporating the compounds into the agar and vapour activities were measured after their evaporation from glass and from moist soil. Vapour activity following evaporation from soil was shown to be a function of both the intrinsic activity of the compound and its partition coefficient between the air and moist soil (Kas). The latter is itself a function of vapour pressure, 1‐octanol/water partition coefficient (Kow) and the soil type. The compound most active as vapour from soil in the in‐vitro test, 1‐(pyridin‐3‐yl)‐2‐(4‐flurorophenyl)pentane, was ineffective against take‐all in wheat in a pot test in which the inoculated soil was treated unevenly, providing further evidence that the redistribution of fungicides in moist soil occurs predominantly via the water phase rather than the vapour phase.
Transformation rate of 1,3‐dichloropropene and 3‐chloroallyl alcohol in topsoil and subsoil material of flower‐bulb fields
Authors: Leistra Minze , Groen Ariette E. , Crum Steven J. H. , van der Pas Leo J. T. 
Published: November 2006

AbstractThe extent of the risk of (Z)‐ and (E)‐1,3‐dichloropropene and their transformation products (Z)‐ and (E)‐3‐chloroallyl alcohol causing a hazard to the quality of groundwater pumped up for public water supply from below flower‐bulb fields has been evaluated. The 1,3‐dichloropropenes were incubated at 10°C in water‐saturated subsoil material from three such fields. A first stage with gradual transformation was followed by a second stage with comparatively rapid transformation and after three months negligible amounts remained. The 3‐chloroallyl alcohols were incubated at 15°C in soils from the root zone of the same fields. Complete transformation had occurred in about a week or even less. The 3‐chloroallyl alcohols were also incubated in the water‐saturated subsoil material at 10°C. Again, a first stage with gradual transformation was followed by a second stage with fast transformation. In most instances, the concentrations had fallen to a very low level within three months. It was concluded that it is unlikely that residues in the upper groundwater would permeate into the deeper groundwater pumped up for public water supply.
Temperature effects on the action of acylurea insecticides against tobacco hornworm (Manduca sexta) larvae
Authors: Chandler Darren R. , King Robert G. , Jewess Philip , Reynolds Stuart E. 
Published: November 2006

AbstractThe toxic effects of six acylurea insecticides on larvae of the tobacco hornworm were investigated at each of four environmental temperatures (20, 25, 30 and 35°C). This spans the range of temperatures which the insects can tolerate. For all the acylureas tested, mortality increased with temperature when either newly hatched or fourth‐instar larvae were given insecticide in their food. Sub‐lethal growth inhibition also became more pronounced at progressively higher environmental temperatures. This temperature dependence of acylurea action was not due to altered uptake of the insecticide, since there was no significant variation with temperature in the amount of [14C]flufenoxuron taken up by fifth‐instar larvae when given a single meal containing labelled insecticide. Additionally, mortality of fourth‐instar larvae given a single intra‐haemocoelic injection of flufenoxuron was significantly greater at higher temperatures, implying that temperature affects a process that occurs after insecticide uptake. The intrinsic ability of acylureas to inhibit chitin synthesis is temperaturesensitive, since flufenoxuron inhibited the incorporation of [14C]N‐acetylalucosamine into chitin by proleg epidermis in vitro significantly less well at 20°C than at the higher temperatures tested. However, there was no significant variation between the effectiveness of in‐vitro chitin synthesis inhibition at 25, 30 and 35°C. These data show that the effectiveness of acylurea insecticides is subject to strong temperature effects in the range of temperatures likely to be experienced in the field.
Fungicidal β‐methoxyacrylates: From natural products to novel synthetic agricultural fungicides
Authors: Beautement Kevin , Clough John M. , de Fraine Paul J. , Godfrey Christopher R. A. 
Published: November 2006

AbstractThe strobilurins and oudemansins are natural β‐methoxyacrylates which inhibit mitochondrial respiration and, as a result, have fungicidal activity. A knowledge of the structures (configuration and conformation) and properties of these compounds has allowed the preparation of analogues in which both fungicidal activity and stability have been improved.
Light‐dependent herbicidal activity of 4‐pyridone‐3‐carboxanilide derivatives against Echinochloa oryzicola
Authors: Osabe Hirokazu , Morishima Yasuo , Goto Yukihisa , Masamoto Kazuhisa , Yagihara Hiroshi , Fujita Toshio 
Published: November 2006

AbstractNovel 4‐pyridone‐3‐carboxanilide derivatives containing various substituents on the anilide benzene and 4‐pyridone rings were synthesized, and their herbicidal activity against Echinochloa oryzicola was evaluated. These compounds exhibited light‐dependent herbicidal activity, except for some 1‐N‐benzyl analogs substituted on the anilide moiety which were light‐independent. Among compounds synthesized, 5‐bromo‐2′,6′‐diethyl‐1,4‐dihydro‐2,6‐dimethyl‐4‐oxo‐1‐phenethylpyridine‐3‐carboxanilide was found to possess the highest light‐dependent herbicidal activity, being almost equivalent with that of oxyfluorfen. The effects of substituents of the anilide benzene and 4‐pyridone rings on the activity are discussed.
Comparative purification methods for determination of triadimenol residues in plant material
Authors: Reynaud Patricia V. , Rolle Sylvaine D. , De Cormis Louis 
Published: November 2006

AbstractTwo procedures are described for the determination of residues of triadimenol and compared on cereal material. After extraction, purification is carried out by Florisil column chromatography in method I and by semi‐preparative High‐Performance Liquid Chromatography in method II. Triadimenol residues are quantified by gas chromatography with a thermoionic detector. With method I, interference was observed but not with method II. This specific procedure has been tested on other plant materials. Recoveries in the range of 90–98% indicate that this procedure is suitable for residue analysis of this fungicide with detection limits of 0·008 mg kg−1 in wheat grains, 0·03 mg kg−1 in wheat straw and 0·004–0·008 mg kg−1 in other plants. Maximum residue limits in France are: 0·1 mg kg−1 in grain, 2·0 mg kg−1 in straw and 1·0 mg kg−1 in other vegetables and fruit.
Cipac collaborative study to test a colorimetric method for determination of the stability of dilute emulsions
Authors: Bernes Albert , Galoux Michel 
Published: November 2006

AbstractA colorimetric method for the determination of the stability of dilute emulsions (down to 1 ml litre−1) of emulsifiable concentrates (EC) has been subjected to a collaborative study with 27 participating laboratories, on behalf of the Collaborative International Pesticides Analytical Council (CIPAC).A dye is added to the emulsifiable concentrate and an aliquot is poured into standard water to obtain an aqueous emulsion. After a specified time, the absorbance of an aliquot of the dyed emulsion is measured and compared to the absorbance measured after initial formation of the emulsion.Collaborators were furnised with four emulsifiable concentrate formulations and the dye, and requested to make three replicate determinations on each dyed sample in CIPAC standard waters A and D.The repeatability and reproducibility figures obtained in these trials indicate that the method permits a good estimation of the stability of dilute emulsions when it is followed exactly.
Resistance to insecticides in winter‐ and summer‐forms of pear psylla, Psylla pyricola
Authors: Van De Baan Hugo E. , Croft Brian A. 
Published: November 2006

AbstractSummer‐form pear psylla, Psylla pyricola Foerster, from sprayed pear were resistant to endosulfan (2·4‐fold), methiocarb (2·5‐fold), ethylan (5·8‐fold), azinphos‐methyl (7·7‐fold), and fenvalerate (40·1‐fold). Esterase (3·8‐fold), glutathione transferase (1·8‐fold), and cytochrome P‐450 monooxygenase (1·6‐fold) detoxification enzyme activity was higher in resistant than in susceptible summer forms. Synergism by piperonyl butoxide and S,S,S‐tributylphosphorotrithioate (DEF) was added evidence for cytochrome P‐450 monooxygenases and esterases as resistance mechanisms. Reduced penetration may also have contributed to resistance, as indicated by a 1·6‐fold slower penetration of azinphos‐methyl in resistant than susceptible summer‐forms. Similar differences in insecticide toxicity and esterase and glutathione transferase activities were observed between winter‐forms of resistant and susceptible pear psylla. Winter‐forms of P. pyricola were up to three times more tolerant to insecticides than summer‐forms. Higher cytochrome P‐450 monooxygenase activity (1·7‐fold) and slower azinphosmethyl penetration (2·1‐fold) in winter‐forms may have contributed to their greater insecticide tolerance; however, sequestration may also have been involved.
The influence of spray droplet characteristics on the efficacy of permethrin against the diamondback moth Plutella xylostella: The effect of drop size and concentration on the potency of ulv‐ and ec‐based residual deposits
Authors: Omar Dzolkhifli , Matthews Graham A. , Ford Martyn G. , Salt David W. 
Published: November 2006

AbstractThe effect of droplet diameter (36‐274 μm) and concentration (10‐400 g litre−1) of permethrin on the knockdown and mortality of 2nd‐instar Plutella xylostella larvae was investigated. Larvae were placed on brussels sprout leaf discs treated with residual deposits of permethrin applied as ULV or emulsion formulations. The LD50 of permethrin decreased with droplet size at all concentrations tested. This effect could not be accounted for solely by increased drop numbers per unit area of leaf, suggesting that for both formulations transfer of permethrin to larvae is more efficient for deposits composed of small drops. The concentration of permethrin in the ULV formulation could be reduced to approach a minimum quantity of toxicant per unit area to maintain 50 per cent mortality. The approach to the minimum dose varied with drop size and drop number per unit leaf area. The ULV formulation was approximately 2.7 times more effective at killing larvae than the emulsion, presumably as a result of greater availability of toxicant and transfer to larvae.
Excitation of central neurons by dieldrin and picrotoxinin in susceptible and resistant Drosophila melanogaster (meigen)
Authors: Bloomquist Jeffrey R. , Ffrench‐Constant Richard H. , Roush Richard T. 
Published: November 2006

AbstractNeurophysiological studies were used to characterize the resistance mechanism in a new cyclodiene‐resistant strain of Drosophila melanogaster. Suction electrode recordings were taken from the peripheral nerves of transected larval central nervous system. Treatment of nerve preparations with 1 mM GABA reduced the spontaneous firing of peripheral nerves. This inhibition was effectively reversed within 10 min by exposing preparations from susceptible insects (Oregon‐R wild type) to 10 μM dieldrin. In contrast, 30 min incubations with 10 μM dieldrin had no effect on preparations from resistant individuals. At 10 μM, picrotoxinin was also effective in antagonizing the action of GABA in susceptible nerve preparations. In recordings from resistant insects (n = 3), picrotoxinin displayed either no antagonism of GABA‐dependent inhibition, weak antagonism of GABA, or hyperexcitation indistinguishable from those of susceptible preparations. These results demonstrate that cyclodiene resistance in the Maryland strain of D. melanogaster is present at the level of the nerve, and that the resistance extends to picrotoxinin, albeit at a reduced level. The possible role of an altered GABA receptor in this resistance is discussed.