bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of oil formulations of deltamethrin for use on cotton targets for tsetse fly control
Authors: Hussain Manzoor , Han Liang‐Feng , Rathor M. Nasir
Published: November 2006

A range of formulations of deltamethrin were prepared, some containing an ultraviolet (UV) absorber compound or a combination of the UV absorber and an oil, and applied to blue cotton tsetse fly target samples which were then exposed to the effect of simulated sunlight and water in the laboratory. The residue of insecticide remaining on the targets and the activity of the latter against tsetse flies was determined. Formulations containing the UV absorber and coconut oil or silicone oil remained the most effective against tsetse flies.

A coconut oil formulation of the insecticide was selected for field evaluation in comparison with a commercial deltamethrin formulation, Glossinex 200′ S.C., which contains 10% UV absorber. Target samples treated with these formulations were exposed to natural tsetse fly habitat in Ghana for a period of five months and evaluated for deltamethrin residues and activity against four species of tsetse fly. After five months, 4–13 times more deltamethrin remained on the targets treated with the coconut oil formulation than on those treated with ‘Glossinex’, and consequently the former were more active against tsetse flies than the latter. Target samples sequentially dipped in the coconut oil formulation resulted in uniform insecticide concentration on the targets, whereas those dipped in ‘Glossinex’ contained gradually decreasing deltamethrin concentrations.
Inhibition of sterol biosynthesis in cell‐free extracts of Botrytis cinerea by prochloraz and prochloraz analogues
Authors: Kapteyn Johan C. , Milling Richard J. , Simpson Donald J. , De Waard Maarten A.
Published: November 2006

The sensitivity of cytochrome‐P450‐dependent sterol 14α‐demethylase (P45014DM) to prochloraz and several prochloraz analogues was studied in a cell‐free assay of Botrytis cinerea Pers. ex Fr. The EC50 values (concentrations which inhibited radial growth of B. cinerea by 50%) of the compounds tested ranged from 3.3 × 10 −8 to 1.7 × 10 −5 M. The IV50 values (concentrations which inhibited cell‐free C4‐demethyl sterol synthesis by 50%) in cell‐free assays of B. cinerea ranged from 2.6 × 10 −9 to 4.4 × 10 −7 M. Ranking compounds in terms of their relative inhibitory potencies showed quite similar trends to the order of fungitoxicity, but the IC50 values did not quantitatively reflect the differences in toxicity. Therefore, the differential inhibition of cell‐free P45014DM activity by these compounds cannot fully account for their differences in activity towards B. cinerea. Additional mechanisms must be involved.

The compounds tested were generally more potent in the B. cinerea assay than in similar assays developed for Penicillium italicum Wehmer and, in particular, Saccharomyces cerevisiae Meyen. This correlated with the relatively higher activity of most test compounds to B. cinerea. Results suggest that the cell‐free assay of B. cinerea is more useful to evaluate candidate fungicides as inhibitors of sterol 14α‐demethyiase activity than similar assays from model organisms.

The present study confirms that the affinity of prochloraz analogues for P45014DM depends on the nature of the N‐1 substituent of the imidazole and the azole ring. It was also found that addition of an amino group at C‐2 of the imidazole moiety of prochloraz gave a compound (6) which inhibited 4, 4‐demethyl sterol biosynthesis in B. cinerea at a different site from the P45014DM. This was confirmed by the observation that laboratory‐generated triadimenol‐resistant isolates of B. cinerea showed reduced sensitivity to triadimenol and prochloraz, but not to compound 6.
Behaviour of the insecticides ethoprophos and carbofuran during soil—water transport
Authors: Dowling Kathryn C. , Costella Ronald G. , Lemley Ann T.
Published: November 2006

The movement of the organophosphate nematicide‐insecticide ethoprophos (ethoprop; O‐ethyl S,S‐dipropyl phosphorodithioate) and the carbamate insecticide‐nematicide carbofuran (2,3‐dihydro‐2,2‐dimethylbenzofuran‐7‐yI methylcarbamate) was studied under steady‐state flow in small‐scale laboratory soil columns. Miscible displacement column experiments, mass balance calculations, and batch incubation studies furnished information on insecticide sorption and degradation processes that occur during transport through soil. Miscible displacement studies demonstrated that ethoprophos degradation could be described as first‐order and that both insecticides exhibited non‐equilibrium sorption. Both batch and miscible displacement results showed ethoprophos to be more strongly sorbed by soil than carbofuran. Measured equilibrium sorption coefficients were 1.29 cm3 g−1 for ethoprophos and 0.29 cm3 g−1 for carbofuran on a Riverhead soil (0.011 organic carbon fraction); 035 cm3 g−1 for carbofuran on Valois soil (0.016 organic carbon fraction); and 2.38 cm3 g−1 for ethoprophos on Rhinebeck soil (0.031 organic carbon fraction). Two solutions to the convection‐dispersion equation, one that incorporated equilibrium sorption and another (bicontinuum model) that included a non‐equilibrium sorption term, allowed quantitative evaluation of transport processes. The bicontinuum model used in conjunction with experimental batch and mass balance techniques provided estimates of insecticide sorption and degradation parameters.
Cuticular penetration of 2,4‐D as affected by interaction between a diethylene glycol monooleate surfactant and apple leaf cuticles
Authors: Tan Siyuan , Crabtree Garvin D.
Published: November 2006

Impacts of pH and sorption‐desorption of ‘Pegosperse’ 100‐O (PEG. 100‐O; diethylene glycol monooleate, containing 15% diester) surfactant by apple (Malus pumila M.) leaf cuticles on surfactant‐enhanced cuticular penetration of 2,4‐D [(2,4‐dichlorophenoxy)acetic acid] were studied. Glass cylinders were affixed to enzymatically isolated adaxial apple leaf cuticles after the cuticle segments had been soaked in 10 ml liter−1 PEG 100‐O solution and washed for 20 and 120 min, respectively. Quantities of [14C]2,4‐D in the glass‐cuticle chambers passing through the cuticles at pH values from 1 to 6 5 were determined. PEG 100‐O significantly increased cuticular penetration of dissociated 2,4‐D at pH 4–5; the surfactant had no effect on penetration of undissociated 2,4‐D at pH 10. Surfactant‐enhanced penetration of 2,4‐D occurred only when the surfactant was in the cuticles, while the process of surfactant sorption‐desorption alone had no effect on penetration. These results support a ‘hydrophilic channel’ hypothesis, i.e. that surfactants may create hydrophilic channels or increase the area of the channels in the cuticle and, consequently, enhance the passing of polar molecules like dissociated 2,4‐D through the cuticle.
Inhibition of pheromone action in Sesamia nonagrioides by Haloacetate analogues
Authors: Riba Magi , Eizaguirre Matilde , Sans Albert , Quero Carmen , Guerrero Angel
Published: November 2006

The electrophysiological activity of some halogenated analogues of the major component of the sex pheromone of the corn stalk borer Sesamia nonagrioides Lef. (1) is presented. The analogues comprise a series of fluoro‐, chloro‐ and bromoacetate analogues4–10 as well as trifluoromethyl ketone 11. The fluoro derivatives 4–6 displayed remarkable electro‐antennogram (EAG) intrinsic activities in comparison with the parent acetate 1, while the remaining analogues elicited significantly lower response. The compounds have also been tested as inhibitors of the sex pheromone perception in EAG and in the field. In the laboratory. fluoro analogues 4–6 were better inhibitors than chloro derivatives 7–9, which in turn behaved similarly to the bromoacetate 10. Trifluoromethyl ketone 11, however, was a poor inhibitor of the pheromone action. In the field, baits of mixtures of compounds 5–11 with the corn stalk borer pheromone in 10:1 ratio inhibited the concomitant attraction of the clover cutworm moth Scotogramma irifolii Rott., while the difluoro analogue 5, trichloroacetate 9 and trifluoromethyl ketone 11 also diminished the number of catches of the armyworm Mythimna unipuncta Haw. The monofluoroacetate 4. trifluoro analogue 6 and bromo derivative 10 significantly disrupted the pheromone action of the corn borer, whereas trifluoromethyl ketone 11 synergistically increased the number of males attracted to the pheromone trap alone. Addition of 11 to baits containing the corn borer pheromone caught S. nonagrioides selectively with regard to the other habitat‐sharing species M. unipuncta and S. trifolii.
HPLC separation and subsequent detection of aromatic heptaene polyenes in peat after treatment with Streptomyces griseoviridis
Authors: Raatikainen Olavi J. , Päivinen Tuulikki H. , Tahvonen Risto T.
Published: November 2006

Aromatic heptaene polyenes (AHPs), the largest group of antifungal polyene antibiotics, were detected in steam‐sterilized Sphagnum peat after treatment with a new biofungicide containing fermenter‐cultivated Streptomyces griseoviridis Anderson K61, a bacterium capable of producing AHPs in vitro. Three concentrations (0.05 g litre−1, 0‐2 g litre−1 and 2.0 g litre−1) of the biofungicide were used and compared to untreated controls. The substrates were incubated for seven weeks under greenhouse conditions, with and without cucumber seedlings, and samples were analysed for heptaene polyenes by HPLC using a photodiode array detector. Changes in AHP concentrations indicated that the fermenter‐cultivated mycelium was a partial source of extractable heptaenes in peat. The identification of p‐aminoacetophenone (PAAP) by HPLC‐MS in peat hydrolysates verified the presence of AHPs.
Modeling root absorption and translocation of 5‐substituted analogs of the imidazolinone herbicide, imazapyr
Authors: Little Desiree L. , Ladner David W. , Shaner Dale L. , Ilnicki Richard D.
Published: November 2006

Quantitative structure‐activity relationships (QSAR) were developed between the physicochemical parameters of the 5‐substituent of a series of analogs of the imidazolinone herbicide, imazapyr, and root absorption, translocation, inhibition of acetohydroxyacid synthase (AHAS), and herbicidal activity of the analogs. An optimum substituent lipophilicity (π = 1.85–2–3) for root absorption was identified for corn (Zea mays L.) and sunflower (Helianthus annuus L.). Translocation from roots to shoots was greatest for those analogs having either highly nonpolar or highly polar 5‐substituents, indicating that both symplastic and apopiastic mechanisms may be functioning. In addition, translocation from roots was positively correlated with electron‐withdrawing parameters of the 5‐substituent, and a possible mechanism governing this relationship is discussed. Modeling in vitro AHAS inhibition was not successful, but models were developed for herbicidal activity as measured in an Arabidopsis thaliana (L.) Hevnh. bioassay. The whole‐plant models described an optimum substituent lipophilicity (π = 0 71) which probably reflected the influence of this parameter on the component processes of absorption and translocation. Whole‐plant activity was also greater for analogs having electron‐donating 5‐substituents; this result suggests that electron donation may be important for metabolism, or more likely, for AHAS inhibition.
The toxicity of the rodenticide flocoumafen to barn owls and its elimination via pellets
Authors: Newton Ian , Wyllie Ian , Gray Alan , Eadsforth Charles V.
Published: November 2006

In a Barn Owl feeding study, five birds were fed with flocoumafen‐dosed mice for consecutive periods of one, three and six days. Following each of these periods the owls were allowed to recover on undosed diet. Four of the birds survived all the treatments, but the fifth bird, which had been moulting prior to the start of the six‐day feeding trial, subsequently died from haemorrhaging five days after the final dose. During the six‐day feeding trial the birds received cumulative flocoumafen doses ranging from 0–78 mg kg−1 to 1‐25 mg kg−1 (0.93 mg kg−1 for the bird which died).

By comparison with previous, analogous studies, flocoumafen appears less toxic to Barn Owls than brodifacoum. However, the relative toxicity of flocoumafen, bromadiolone and difenacoum cannot be ascertained from these studies because the dose rates were not comparable.

Chemical analysis of regurgitated Barn Owl pellets indicated that a substantial amount (mean 27%) of the consumed flocoumafen was eliminated unchanged in the pellets during the dosing periods. After dosing ceased, the flocoumafen content in pellets decreased rapidly. These data confirm those from a preliminary single‐dose study and substantiate the use of pellet analysis as a sensitive and selective method for non‐invasive monitoring of the exposure of Barn Owls to anticoagulant rodenticides in their prey. Analysis of liver residues from both the owl which died and those which survived indicated that flocoumafen is slowly eliminated from this organ with a terminal elimination (β‐phase) half‐life probably in excess of 100 days.
Feeding deterrence of northern fowl mites (acari: Macronyssidae) by some naturally occurring plant substances
Authors: Carroll John F.
Published: November 2006

Eighteen of 21 naturally occurring compounds and plant extracts tested in an in‐vitro feeding system deterred northern fowl mites, Ornithonyssus sylviarum (Canestrini and Fanzago), from feeding. At 1.0% (w/v) concentrations in chicken blood, five compounds killed all mites exposed to them. Citronellal and bay extract prevented mite feeding completely at 0.1% concentrations. None of the compounds or extracts had repellent activity when mites were surrounded by a ring of the test material (0–42 mgcm−2) impregnated in filter paper.
Synthesis of pyrethroic acids from natural products and from isomeric compounds: Strategy and practice
Authors: Krief Alain
Published: November 2006

Pyrethroic acids are essential constituents of the pyrethroids, which are now some of the most powerful commercially available insecticides. A number of syntheses of pyrethroic acids have been published since the elucidation of the structure of chrysanthemic acid, one of the naturally occurring acids present as esters in Chrysanthemum cinerarefolium Vis. This paper reports some results of the stereoselective synthesis of the most biologically active enantiomers of pyrethroic acids obtained over the last five years in our laboratory. Two different approaches, which have been patented by two leading European companies in the agrochemical field, have been carried out simultaneously. The first uses the cheap chiral natural products mannitol and tartaric acid as starting materials and allows the rapid construction of the cyclopropane framework. The second takes advantage of the isomeric relationship between dimethyl dimedone, a readily available, non‐chiral compound and chrysanthemic acid. Enantioselective isomerisation of dimethyl dimedone to (1R)‐cis‐ and (1R)‐trans‐chrysanthemic acid has been achieved successfully using a lipase. These two approaches to the synthesis of chrysanthemic acid are compared with related approaches in the literature, which use other natural products or isomers of chrysanthemic acid as starting materials.
Recent advances in the stereoselective synthesis of L‐phosphinothricin
Authors: Zeiss Hans‐Joachim
Published: November 2006

L‐Phosphinothricin, the parent α‐amino acid of the herbicide glufosinate‐ammonium, has been obtained in high enantiomeric purity by three different methods. The stereoselective alkylation of a D‐valine‐derived bis‐lactim ether, followed by the hydrolysis of the heterocyclic intermediate, represents an attractive approach for gram‐scale quantities in the laboratory. Another very efficient access to L‐phosphinothricin consists of the asymmetric hydrogenation of a prochiral α‐acylamido acrylate with a chiral bis‐phosphine‐rhodium catalyst, while the reaction of chiral pre‐built C‐4‐fragments, like L‐vinylglycine or L‐2‐amino‐4‐halobutyric acid, which can be obtained from the inexpensive starting materials L‐aspartic acid and L‐glutamic acid, with (methyl)phosphinic acid derivatives represents a third route which allows the production of nearly enantiomerically pure L‐phosphinothricin.
The synthesis of pyrroles with insecticidal activity
Authors: Kuhn David G. , Kamhi Victor M. , Furch Joseph A. , Diehl Robert E. , Lowen Gregory T. , Kameswaran Venkataraman
Published: November 2006

The 2‐aryl‐4‐bromo‐5‐trifluoromethylpyrrole‐3‐carbonitriles represent a new class of insect control agents. The high insectidical activity observed in this series prompted us to investigate the preparation of regioisomeric arylhalotrifluoromethylpyrrole carbonitriles. The synthesis and biological activity of eight of the twelve possible regioisomers are described and discussed.
Derivatives of pesticides with an α‐amino acid function: Synthesis and effect on threonine uptake
Authors: Dufaud Annie , Chollet Jean‐François , Rudelle Jérǒme , Miginiac Léone , Bonnemain Jean‐Louis
Published: November 2006

The synthesis of several derivatives of a pesticide and an α‐amino acid are described. The process involves three steps, the last one (deprotection of the α‐amino acid group) being the most critical. The resulting products preserved their α‐amino acid group and were globally neutral. They were tested for their effect on the transport of a neutral amino acid, threonine, and two sugars, sucrose and glucose. Two derivatives markedly and specifically inhibited threonine uptake by leaf tissues of Vicia faba L. and phloem loading. Preliminary experiments suggested that the lysine‐2,4‐D derivative is a competitive inhibitor of threonine uptake. The apparent Ki (0.5 mM) was much lower than the apparent Km (3 mm) of the natural substrate.
Non‐invasive method for monitoring the exposure of Barn owls to second‐generation rodenticides
Authors: Gray Alan , Eadsforth Charles V. , Dutton Alan J. , Vaughan John A.
Published: November 2006

Chemical analysis of rodenticide residues in regurgitated owl pellets has been shown to be a sensitive, non‐invasive method for monitoring the potential exposure of Barn Owls to second‐generation rodenticides in their prey. The method, originally developed for flocoumafen, has been extended to two other rodenticides. brodifacoum and difenacoum.

The method was validated as part of a toxicity study in which Barn Owls were separately fed 40–130 μg day −1 of brodifacoum, difenacoum and flocoumafen in mice over 15 days. Each day an average of 25% of the consumed rodenticide was regurgitated in the pellets.
Analysis of human sweat volatiles: An example of pattern recognition in the analysis and interpretation of gas chromatograms
Authors: Sommerville Barbara A. , McCormick James P. , Broom Donald M.
Published: November 2006

The analysis of the volatile components of human body odour is described with a view to establishing how individual identity can be reflected in an odour profile. In order to get good chromatographic replication, a recirculating system was built to load the samples of axillary sweat head‐space into Tenax concentrating traps. The loading temperature and humidity could be controlled and trace volatiles concentrated. The head‐space samples were desorbed from the trap and analysed by GLC. The GC/FID was interfaced with an ATARI ST 1040 computer which stored the output on disc. Pairs of chromatograms were then compared in a pattern‐matching programme which allowed irrelevant differences, such as variations in running time and sample size, to be corrected and then various match parameters to be measured. These were alignment coefficient, profile correlation. Euclidian distance and box car distance. The whole and selected parts of the chromatograms could be matched so that each range of volatiles could be assessed for its contribution to an identity signal.

The pattern of sweat volatiles from two pairs of identical twins showed significantly higher match correlations than that of unrelated people. The range of compounds eluting between 80 and 150 C showed the highest match correlations.

These techniques could be used to match chromatograms from any source, for example, in drugs and pesticide research, environmental monitoring, food, flavour and perfume analysis or clinical and forensic investigations.
Spectrophotometric determination of ziram and zineb using 4‐(2‐pyridylazo) resorcinol
Authors: Kapoor Jyoti , Rao A. L. J.
Published: November 2006

A spectrophotometric method has been developed for the determination of ziram (zinc bis(dimethyldithiocarbamate)) and zineb (zinc ethylenebisdithiocarbarnate) by converting these into a zinc‐4‐(2‐pyridylazo)resorcinol complex, which is dissolved in acetone and water and the absorbance measured at 490 nm against a reagent blank. Beer's law is obeyed over the concentration ranges 0.025‐1.25 and 0.025‐1.5 mg litre−1 for ziram and zineb respectively in the final solution. The method is sensitive and can be used for the direct determination of ziram and zineb in commercial formulations, grains (rice and wheat) and synthetic mixtures (in the presence of various other dithiocarbamates). The limit of determination of ziram and zineb from foodstuffs in 0.2 mg kg −1.
Managing resistance in Bemisia tabaci in Israel with emphasis on cotton
Authors: Horowitz A. Rami , Forer Gadi , Ishaaya Isaac
Published: November 2006

At the beginning of the 1990s, insecticides with novel modes of action, such as buprofezin, pyriproxyfen and diafenthiuron, were introduced for controlling the whitefly Bemisia tabaci (Gennadius) in cotton and other crops. In order to delay the onset of resistance to these novel insecticides, as well as to the efficient conventional ones, an insecticide resistance management (IRM) strategy was implemented in 1987 in cotton fields in Israel. The main purposes have been to combat resistance to available, efficient insecticides and to prolong the life‐span of new insecticides by optimizing their use and preserving natural enemies during the peak of their activity. A rotation programme was applied, using insecticides of different modes of action, rotated according to the generation duration of the relevant pests. The strategy included explanatory and educational campaigns, and was accompanied by an extensive resistance monitoring programme conducted throughout the year in greenhouses and during the summer in cotton fields. Bioassays of whiteflies collected from cotton fields indicated that one treatment with pyriproxyfen in cotton fields during a one‐month period, followed by an additional treatment with buprofezin (if required), did not markedly alter the susceptibility of B. tabaci to either compound. In addition, no appreciable increase of resistance to the available conventional insecticides was observed, although some changes in susceptibility were noticed during the cotton season. In some greenhouses without an IRM programme, a c.tenfold increase in resistance to buprofezin was found after two or three applications of this compound in each season. A c.500‐fold increase of resistance to pyriproxyfen was recorded after three successive applications of this compound in a greenhouse. These findings demonstrate the necessity for an IRM strategy to be implemented in both open fields and greenhouses.
Possible methionine biosynthesis inhibition by pyrimidinamine fungicides
Authors: Masner Petr , Muster Peter , Schmid Jacqueline
Published: November 2006

The broad‐spectrum fungicide CGA 219417 inhibits mycelial growth of Botrytis cinerea Pers ex Fr. Pseudocercosporella herpotrichoides (Fron.) Deighton and Helminthosporium oryzae B. de Haan on defined media lacking amino acids. The growth inhibition of B. cinerea is reversed by the addition of a mixture of 19 amino acids at a concentration of 100 μM each or by the addition of methionine or homocysteine in concentrations of 100 μM or 1 mM, respectively. In the case of B. cinerea, the reversal of growth inhibition by methionine could also be shown for pyrimethanil and mepanipyrim. These findings suggest that the pyrimidinamine fungicides inhibit the biosynthesis of methionine in phytopathogenic fungi.
Insecticidal activity of synthetic 2‐carboxylbenzofurans and their coumarin precursors
Authors: Williams Lawrence A. D. , Anderson Mario J. , Jackson Yvette A.
Published: November 2006

Several 2‐carboxylbenzofurans and their coumarin precursors, compounds 1–6, and the novel compound 7 were synthesized and their insecticidal activity studied using adult sweet potato weevils (Cylas formicarius elegantulus (Summer)) at 24 μg, 48 μg and 72 μg per insect in 0.5 ml litre−1 piperonyl butoxide (PPB) in acetone. The order of toxicity of the compounds as judged by the percentage mortality at 24 μg per insect at 48 h was 2 (100%) > 6 (95%) > 7 (85%) > 4 (75%)) > 3 (65%) > 1 (60%) > 5 (45%) > piperonyl butoxide (0.0%).

Compound 2 was equitoxic to 24 μg of technical grade dimethoate. When administered in acetone alone, however, the compounds were only moderately active (i.e. > 120 μg per insect was required for 60% mortality at 48 h). The test compounds were more active at lower doses (48–72 μg per insect) when dissolved in dimethylsulfoxide or in an oil extract obtained from the fruit of Blighia sapida Koenig.
Detoxification and activation of agrochemicals in plants
Authors: Cole David J.
Published: November 2006

Plants are able to metabolize agrochemicals and other foreign compounds by a variety of mechanisms and with extraordinary species diversity. Minor structural alterations of these compounds can bring about dramatic and unpredictable changes in the routes of their metabolism. The enzymes responsible for this exist in multiple forms which renders prediction of herbicide metabolism and, therefore, of selectivity, difficult. In some notable instances, pesticides are activated by plant metabolism. In the main, however, mechanisms such as hydroxylation, dealkylation and glutathione conjugation bring about detoxification and form the basis of herbicide selectivity. The properties of oxygenating and conjugating enzymes in plants are highlighted, with emphasis on the evident narrow substrate specificities, species differences and physiological roles. The molecular cloning of the genes specifying these enzymes will permit a much better definition of these mechanisms and will illuminate the natural roles of the enzymes involved. The prospects for utilizing recombinant enzymes as tools for the rational design of new selective herbicides are discussed. Herbicide safeners can protect certain crops from herbicide injury by promoting herbicide metabolism. The precise mechanisms of safener action and the reasons for their specificity are attracting much interest but are at present obscure. Natural variation in detoxification abilities of weed populations has allowed the field selection of some biotypes resistant to repeatedly used herbicides. By analogy, the introduction of microbial detoxification genes into major crops through genetic transformation has created new herbicideresistant crops which will enhance the flexibility of herbicide usage.
Triazolines. XXIX. 1,5‐diaryl‐Δ2‐1,2,3‐triazolines as aphicides: Mechanism of action via aziridine formation
Authors: Kadaba Pankaja K.
Published: November 2006

The aphicidal activity of 21 different 1,5‐diphenyl‐Δ2‐1,2,3‐triazolines, conveniently prepared utilizing the catalytic effect of water on the 1,3‐cyclo‐addition of diazomethane to Schiff bases in aqueous dioxane, was evaluated. Triazolines bearing an o‐Cl substituent on the C‐phenyl, either alone (4) or in combination with a m‐ and/or a p‐substituent on the N‐phenyl (14, 15, 17 and 18), showed significant activity, with a combined m‐, p‐ substitution on the N‐phenyl the most effective (17 and 18). While an o‐Cl substituent led to greater activity than an o‐NO2 group, the introduction of an additional p‐Cl substituent on the C‐phenyl eliminated activity (21).

The aphicidal activity of triazoline 18 was found to be dependent on the presence of UV light. Since fluorescent lighting used in the testing procedure contains UV light and since triazolines undergo photolysis when exposed to UV light to yield aziridines, it was logical to conclude that the aphicidal activity of the triazolines was, in fact, derived from the aziridines formed during the testing procedure. This mechanism of action was confirmed by preparing the aziridines 22, 23 and 24 corresponding to the active triazolines 14, 15 and 18, and showing that they possessed aphicidal activity equal to or better than that of the triazolines, and by the activity observed in several other structurally related aziridine analogues (25–28). Unlike aziridinyl phosphorous compounds, the aziridines described here are not mutagenic in the Ames assay and thus afford a safer class of pesticides.
A survey comparing the chemical composition of dicofol formulations sold in the UK before and after the introduction of the EC ‘prohibition directive 79/117/EEC’
Authors: Gillespie Margaret J. , Lythgo Christopher M. , Plumb Andrew D. , Wilkins John P. G.
Published: November 2006

Analysis of 38 formulations marketed by five companies indicated that the active ingredient contents of these products are within the range of 92 to 112%, for dicofol, and 107 to 142%, for tetradifon, of that declared. Manufacturing procedures for dicofol produce impurities related to DDT. The adoption of a prohibition directive in Europe requires that DDT‐related impurities represent less than 1 g kg−1 of the dicofol content. Formulations manufactured before the prohibition directive contained these impurities at up to 575 g kg−1 of the dicofol in the formulation. Formulations manufactured after the directive contained these impurities at up to 7 g kg−1 of the dicofol in the formulation. Fewer impurities were detected in the more recent formulations; only o,o′‐DDE, o,m′‐DDE, o,p′‐DDE, m,p′‐DDE, p,p′‐DDE, o,p′‐chloro‐DDT and p,p′‐chloro‐DDT were present. Eight of the 13 samples contained DDT‐related impurities at less than 0.1 g kg−1 of the dicofol in the formulation. The major impurities found in formulations manufactured after the directive (in concentration terms) are non DDT‐related manufacturing byproducts such as o,p′‐dichlorobenzil.
Inhibition of juvenile hormone biosynthesis and methyl farnesoate epoxidase activity by 1,5‐disubstituted imidazoles in the cockroach, Diploptera punctata
Authors: Unnithan Gopalan C. , Andersen John F. , Hisano Tomomi , Kuwano Eiichi , Feyereisen René
Published: November 2006

Seventeen substituted imidazoles were tested as inhibitors of juvenile hormone (JH) III synthesis by cockroach corpora allata in an in‐vitro radio‐chemical assay. Most of these 1,5‐disubstituted imidazoles were highly potent, with IC50 values of less than 100nM. The compounds differed in their ability to cause an accumulation of the precursor methyl farnesoate in the glands. Four of the imidazoles were tested by topical application to previtellogenic adult females, and all caused a significant inhibition of JH synthesis and an accumulation of intraglandular methyl farnesoate for at least three days after treatment. Methyl farnesoate epoxidase activity of homogenates of corpora allata was inhibited by the compounds TH‐14 and TH‐27. This P450‐dependent epoxidase activity was inhibited at less than 10 nM. The results show that the 1,5‐disubstituted imidazoles are powerful inhibitors of the last step of juvenile synthesis in this cockroach.
Xenobiotic glucosyltransferase activity from suspension‐cultured Glycine max cells
Authors: Gallandt Eric R. , Balke Nelson E.
Published: November 2006

Proteins extracted from suspension‐cultured soybean (Glycine max (L.) Merr. Corsoy 79) cells contained O‐ and N‐glucosyltransferases (GTs; EC 2.4.1) that catalyzed glucosylation of several xenobiotic compounds including (a) the hydroxylated herbicide metabolites 6‐hydroxybentazone (B‐6‐OH), 8‐hydroxybentazone and 5‐hydroxydiclofop (b) the herbicide chloramben and (c) the environmental contaminants 2,4‐dichlorophenol and 3,4‐dichloroaniline. The O‐GT that catalyzes B‐6‐OH glucosylation, UDP‐glucose: B‐6‐OH glucosyltransferase (B6GT), was chosen for further study. A rapid and sensitive B6GT assay was developed that uses ethyl acetate extraction to separate the product 6‐O‐[14C]glucosylbentazone from the glucose donor uridine[5′]diphospho‐[1]‐α‐D‐[U‐14C]glucose. B6GT, recovered in the soluble protein fraction, was extracted in consistently high amounts from Corsoy 79 cells cultured for one to seven days. 2‐Mercaptoethanol in the extraction buffer increased B6GT activity as did sodium, potassium, calcium, magnesium or manganese(II) chlorides in the assay buffer. B6GT activity in an ammonium sulfate fraction (30–50% saturation pellet) displayed two pH optima, one at pH 5.5 and another at pH 10 to 11. Apparent Km values for UDP‐glucose and B‐6‐OH in the ammonium sulfate fraction were 90 and 4.5μM, respectively. Thus, we have partially characterized glucosylation of B‐6‐OH, one example of the several xenobiotic GT activities present in Corsoy 79 soybean.
Anticoagulant resistance in Europe: Appraisal of the data from the 1992 EPPO questionnaire
Authors: Myllymäki Arvo
Published: November 2006

Resistance to the first successful anticoagulant rodenticide, warfarin, was detected in the Norway rat (Rattus norvegicus Berk.) in 1958, and it has since expanded to cover other commensal rodent species (R. rattus L., Mus musculus L.) and the majority of later‐developed anticoagulant compounds. The purpose of this paper is to give an up‐to‐date picture of the current distribution of anticoagulant resistance in Europe, as revealed by the questionnaire dispatched by EPPO (European and Mediterranean Plant Protection Organization) to its member countries in 1992. Replies were received from 13 countries (43% of EPPO members), and it was found that broad‐spectrum resistance occurred in practically all those countries that reported testing activity. A likely conclusion based on this finding is that true distribution of resistance is certainly more extensive than documented by the questionnaire replies. Another conclusion drawn by the EPPO Rodent Control Panel was that the existing resistance detection protocols were no longer adequate to cover the whole array of existing anticoagulant rodenticides. Consequently, a new guideline including novel methods particularly for detecting resistance to single‐dose anticoagulant compounds was urgently needed. This guideline is currently under review.
Interaction of benzimidazole‐N‐sulfonamides with the cytochrome b/c1 complex of Pythium aphanidermatum
Authors: Pillonel Christian
Published: November 2006

Experiments with intact cells and submitochondrial fractions of Pythium aphanidermatum (Edson) Fitz. indicated an interference of benzimidazole‐N‐sulfonamides with the NADH‐ or succinate‐driven electron transport system between cytochromes b and c. Comparison with Ustilago maydis (DC) Corda and Botrytis cinerea Pers. ex Fr. revealed that this effect is Oomycetes specific. The molecular interaction between benzimidazole‐N‐sulfonamides and the mitochondrial cytochrome b/c1 complex from P. aphanidermatum has been investigated. Binding assays with [14C]52232 RP (dimefluazole) indicated a time‐ and dose‐dependent labelling of two proteins. The molecular mass of one labelled protein and the competition of the binding with antimycin A suggest that benzimidazole‐N‐sulfonamides interact with the Q1‐centre of cytochrome b. Furthermore, experiments with doubly labelled [3H][14C]CGA 323103 revealed a possible irreversible inactivation of the b/c1 complex leading to covalent linkage of the dimethylsulfonamoyl moiety to the target site.
The determination of abamectin from soil and animal tissue by supercritical fluid extraction and fluorescence detection
Authors: Brooks Matthew W. , Uden Peter C.
Published: November 2006

The insecticide abamectin is extracted from soil and animal tissue by supercritical fluid extraction. Supercritical carbon dioxide modified with 9% 2‐methoxyethanol extracted abamectin from soil samples at levels up to 11 ng g−1 with greater than 80% efficiency. Recovery at fortification levels of 5 ng g−1 were obtainable without the need for clean‐up. Abamectin was also easily extracted from animal tissue at levels of 22ng g−1 without interfering coextractives. Extracted abamectin was determined by liquid chromatography of a fluorescent derivative.
Reinvestigating adjuvants for the wild oat herbicide, flamprop‐M‐isopropyl. I: Glasshouse trials
Authors: Grayson B. Terence , Boyd Sarah L. , Walter David
Published: November 2006

Commercial formulations of flamprop‐M‐isopropyl and formulations of other members of this class of herbicide have always contained an oil adjuvant to increase herbicidal performance. Further increases of performance could be obtained by following the label recommendations to add further quantities of a commercial emulsifiable oil (e.g. ‘Swirl’). Nevertheless it was judged that, in view of current advances in adjuvant research, even greater improvements in herbicidal performance could be obtained with different types of adjuvants.

Experimental trials using a cultivated oat (Avena sativa L.) assay under glasshouse conditions to test ranges of surfactants (alkyl aryl, alkyl saccharide, alkylamine and alcohol ethoxylates) and emulsifiable oils (paraffinic/naphthenic, rape seed, transmethylated rape seed) showed that all of these adjuvants were capable of increasing flamprop‐M‐isopropyl activity compared with that of an emulsifiable concentrate formulation containing no adjuvant. Alkylamine and alcohol ethoxylates, with no particular preference for the length of the alkyl chain, but optimum ethylene oxide content of 5 moles and 7–10 moles respectively, were the most efficacious and better than the current emulsifiable oil system. There was no additional benefit from mixture of these two types of adjuvant and an alcohol ethoxylate (‘Dobanol’ 25‐7) was preferred on cost grounds. This adjuvant also gave substantial activity to the otherwise inactive suspension concentrate formulation. Final trials determined that the optimum application rate of ‘Dobanol’ 25–7 was in the range 1000–1500 g ha−1, and this information guided the design of subsequent field trials.
Reinvestigating adjuvants for the wild oat herbicide, flamprop‐M‐isopropyl. II: Field performance
Authors: Murphy Michael W. , Craven Matthew L. , Grayson B. Terence
Published: November 2006

A field trials programme was conducted in which the performance of a new emulsifiable concentrate formulation (ECI) of flamprop‐M‐isopropyl containing the adjuvant, ‘Dobanol’ 25‐7, in a ratio of 2:1 (by weight) with the AI, was compared with the current commercial formulation of ‘Commando’, in combination with its recommended adjuvant, ‘Swirl’, for the control of wild oat (Avena fatua L.) in wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.). A further treatment, in which the ‘Dobanol’ 25‐7: AI ratio was increased to 4:1 by the spray tank addition of the former, was also included.

The mean results from six trials (five wheat, one barley) showed that the addition of ‘Swirl’ to ‘Commando’ was beneficial, increasing wild oat floret control from a mean value of 80% to 92% at current recommended rates (flamprop‐M‐isopropyl, 600 g ha−1; ‘Swirl’, 2.5 litre ha−1). However, combinations of flamprop‐M‐isopropyl and ‘Dobanol’ 25‐7 gave superior levels of control even at lower AI application rates. For example, a mean level of 96% control of Avena spp. was obtained at 300 g AI ha−1 with 1200 g ha−1 ‘Dobanol’ 25–7; with even better control at higher rates of application of both components.

This improvement in performance was accompanied by a higher risk of crop phytotoxicity than observed with the ‘Commando’/‘Swirl’ mixtures. Symptoms initially were scorch and subsequently growth depression, particularly of tillers. None of the mean values in the six ‘efficacy’ trials reached commercially unacceptable levels, but in a further six ‘crop effects’ trials (three wheat, three barley), in which double rates were applied, the levels of phytotoxicity did become unacceptable and subsequently reduced grain yields. In contrast, two barley ‘crop effects’ trials gave yields higher than the control plots, possibly through the effects of reducing stem length and lodging thereby enabling more efficient harvesting.

Nevertheless, there were rates of application of flamprop‐M‐isopropyl in the range 300–400 g ha−1 with ratios of ‘Dobanol’ 25‐7 in the range 2:1 to 4:1 that would achieve high levels of control of Avena spp. without undue risk of crop phytotoxicity and further trials are planned to support this new adjuvant system.
Polymerase chain reaction‐based monitoring techniques for the detection of insecticide resistance‐associated point mutations and their potential applications
Authors: Ffrench‐Constant Richard , Aronstein Kate , Anthony Nicola , Coustau Christine
Published: November 2006

The design of three PCR‐based monitoring techniques for the genotyping of cyclodiene‐resistant insects are described: (1) PCR followed by a diagnostic restriction enzyme digest or PCR/REN, (2) PCR amplification of specific alleles or PASA and (3) single‐stranded conformational polymorphism analysis of PCR‐amplified DNA or SSCP. The relative disadvantages and potential applications of each of these techniques are discussed and compared to the use of insecticide bioassays. It is concluded that, although such techniques will probably never replace bioassays for routine monitoring, they can more readily address several fundamental questions relating to the evolution and spread of specific resistance alleles in insect populations.
Alterations in phytosterol profiles of Galium aparine following treatment with BAS 480F
Authors: Benton Joanne M. , Cobb Andrew H. , Loeffler R. Thomas
Published: November 2006

The following are extended summaries based on posters presented at the 8th International Congress of Pesticide Chemistry (IUPAC), held in Washington, DC, USA 4–9 July 1994. They are entirely the responsibility of the authors, and do not necessarily reflect the views of the Editorial Board of Pesticide Science.
Characterization of new photosynthesis‐inhibiting imidazolidine derivatives. 2. Interpretation of pre‐emergence herbicidal performance from photosyghesis‐inhibiting activity and soil adsorption coefficient
Authors: Chiba Misako , Yanase Daisuke , Andoh Akihide , Gotoh Takeshi
Published: November 2006

Ruling factors governing pre‐emergence herbicidal activity were analysed for 16 photosynthesis‐inhibiting 5‐hydroxy‐3‐methyl‐2–oxo‐imidazolidine‐1‐carboxamide derivatives. Herbicidal performance was quantified by the reduction in area of experimental weed vegetation, measured by a computer‐aided image analysis system. A system for fluorometric estimation of photosynthesis inhibitor concentration in aqueous solution greatly facilitated determination of the soil adsorption coefficients (Kd). Maximum herbicidal performance was found for N‐sec‐butyl‐5‐hydroxy‐3‐methyl‐2‐oxo‐imidazolidine‐1‐carboxamide, a compound with the second lowest soil adsorptivity and average photosynthesis‐inhibiting activity. A multiple regression analysis suggested that herbicidal performance of the soil‐applied imidazolidine derivatives was determined by a balance between Kd and photosynthesis‐inhibiting activity. In the present experimental system, however, the main influence was attributed to Kd.
Disappearance of carbosulfan residues in peaches
Authors: Barba A. , García S. Navarro , Cámara M. A. , Molina R. , Buendia J.
Published: November 2006

The disappearance kinetics of the carbamate insecticide, carbosulfan, applied at 2 kg AI ha−1 (‘Marshal’ 250 g litre−1 EC) in peaches was studied. Degradation took place in two consecutive stages (0–28 and 28–57 days), with half‐lives of 7.4 and 17.5 days, respectively. The residues obtained 57 days after treatment did not exceed 0.2 mg kg−1. When treatments were carried out 30, 21 and 14 days before the probable date of harvest (date of fruit maturation) with two doses (1.0 and 2.0 g formulated product litre−1) and two volumes applied (750 and 1500 litre ha−1), the residual levels detected were between 0.122 mg kg−1 (30 days before harvest) and 0.4 mg kg−1 (14 days before harvest). The major metabolite, carbofuran, was never detected above its determination limit of 0.004 mg kg−1 throughout the whole study.
Synergism of insecticidal action and effects on detoxifying enzymes in vivo of lambda‐cyhalothrin and malathion by some nitrogen heterocycles in resistant and susceptible strains of Tribolium castaneum
Authors: Wilkins Richard M. , Saleem Mushtaq A. , Rajendran Candasamy
Published: November 2006

The interactions of the synthetic pyrethroid, lambda‐cyhalothrin and malathion were studied with purines, pyrimidines, caffeine and some other related nitrogenous compounds in resistant and susceptible strains of Triboliurn castaneum (Herbst.) The results were compared with those obtained with a known synergist, piperonyl butoxide (PBO) and precocene I. Adenine, cytosine, guanine, thymine and uracil synergised lambda‐cyhalothrin, especially in the susceptible strain, with maximum effect at a 1:1 mass ratio, with the effect decreasing with increasing proportion of the heterocycle. The order of synergism of lambda‐cyhalothrin was; precocene I > PBO > the nitrogenous compounds, in both resistant and susceptible strains. On the other hand, caffeine (lethal effect increased about twice), barbital (about twice), isobarbituric acid (less than twice) and bromacil (up to eight times) synergised malathion in malathion‐resistant strains and antagonised in the susceptible strains. Total in‐vivo esterases, carbox‐ylesterases and cytochrome P450 of susceptible and resistant strains showed significantly increased activity or content when treated with either insecticide plus a heterocyclic compound. Exceptions were with bromacil and malathion and for the malathion‐specific strain, Kano‐C with malathion and the N‐heterocycles.
Quantitative structure—activity studies of insect growth regulators. XI. Stimulation and inhibition of N‐acetylglucosamine incorporation in a cultured integument system by substituted N‐tert‐butyl‐N,N′‐dibenzoylhydrazines
Authors: Nakagawa Yoshiaki , Soya Yoshihiro , Nakai Katsumi , Oikawa Nobuhiro , Nishimura Keiichiro , Ueno Tamio , Fujita Toshio , Kurihara Norio
Published: November 2006

The ability to stimulate N‐acetylglucosamine (GluNAc) incorporation in‐vitro of a number of N‐tert‐butyl‐N,N′‐dibenzoylhydrazines having various substituents on both phenyl rings was measured in cultured integument excised from the rice stem borer (Chilo suppressalis Walker). The relationship between in‐vitro and larvicidal potency was approximately linear. The substituent effects on variations in the potency were similar between in‐vitro and larvicidal activities. An inhibitor of oxidative detoxication, piperonyl butoxide, had no synergistic effects on the in‐vitro potency. The ability of some dibenzoylhydrazines to inhibit GluNAc incorporation at exposure periods longer than the optimum for stimulation was also measured in a similar cultured integument system. The relationship between the inhibitory and stimulatory potency indices was linear, indicating that the larvicidal activity of dibenzoylhydrazines is closely related to its ability to stimulate as well as to inhibit GluNAc incorporation into the larval cuticle.