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The removals of chlorothalonil, pyrazophos, and carbendazim residues form pakchoi by ultrasonic treatment were investigated in this study. The ultrasonic treatment has higher efficiency on the removal of pesticides compared to traditional water soaking. The removal rates of ultrasonic treatment for chlorothalonil, pyrazophos, and carbendazim residues were in the range of 13.87–74.86%, 21.74–45.68%, and 5.12–24.63%, respectively. The removal rates increased with the increase of ultrasonic power, while decreased with the increase of ultrasonic frequency. Besides, the physical damage and vitamin C loss for pakchoi leaves caused by ultrasonic treatment were also evaluated. Results showed that both the physical damage and vitamin C loss increased with the increase of ultrasonic power but decreased with the increase of ultrasonic frequency. A simple three-variable linear model was built up to estimate the loss of vitamin C according to the physical damage on leaves. In conclusion, ultrasonic treatment is an effective technique for the removal of pesticide residues from leafy vegetables. Ultrasonic condition should be considered to avoid the physical damage and the vitamin C loss for vegetables.

Methods to test the side effects of pesticides on adults as well as young stages of the predatory mite Phytoseiulus persimilis Athias-Henriot are described. The effects of 11 pesticides frequently used in integrated pest management programmes for glasshouse crops were tested on three different strains of the predator. Two of these strains (from the Glasshouse Crops Research Institute in Littlehampton, England and the Dutch company Koppert) are commercially used m several European countries to control the two-spotted spider mite Tetranychus urticae Koch. The third strain (from the University Stuttgart-Hohenheim) has been kept in laboratory rearings for at least 28 years without exposure to pesticides. Exposing P. persimilis adult females to a fresh dry pesticide film applied on potted bean plants as well as directly spraying the juvenile stages of the predator showed that the strain “Koppert” was resistant to the fungicide pyrazophos (Afugan WP 30) and less susceptible to the aphicide pirimicarb (Pirimor Granulat) as well as the fungicide dichlofluanid (Euparen) compared to the strains “Hohenheim” and “Littlehampton”. The fungicides triadimefon (Bayleton spezial), vinclozolin (Ronilan), ditalimfos (Frutogard), dodemorph-acetat (BASF-Mehltaumittel) were harmless to all the three strains of P. persimilis. The fungicides bupirimat (Nimrod) and dichlofluanid (Euparen) and triforine (Saprol) were harmless to the three strains in the adult test but slightly harmful to moderately harmful in the juvenile test to the strains “Hohenheim” and “Littlehampton” and harmless to slightly harmful to the strain “Koppert”. The insecticides pirimiphos-methyl (Actellic 50) and pyrethnne + piperonylbutoxide (Spruzit-Nova-flussig) were harmful in both tests to all the three strains. The use of the resistant “Koppert” strain allows the chemical control of mildew, aphids and thrips without adversely affecting the predator. Zusammenfassung Relative Toleranz von drei verschiedenen Zuchtlinien der Raubmilbe Phytoseiulus persimilis A.-H. gegenuber 11 in Gewachshauskulturen verwendeten Pflanzenbehandlungsmitteln Es werden Methoden zur Prufung der Nebenwirkung von Pflanzenbehandlungsmitteln auf Imagines und Jungstadien der Raubmilbe Phytoseiulus persimilis Athias-Henriot beschrieben. Die Wirkung von 11, im Rahmen von integrierten Pflanzenschutzprogrammen haufig angewandten, Prapapaten wurde an drei verschiedenen Zuchtlinien des Nutzlings gepruft. Zwei dieser Zuchtlinien (vom Glasshouse Crops Research Institute in Littlehampton, England, und von der Firma Koppert & Sohn, Berkel en Rodenrijs, Niederlande) finden bei der Bekampfung der Gemeinen Spinnmilbe Tetranychus urticae Koch in mehreren europaischen Landern kommerzielle Anwendung, die dritte Zuchtlinie (von der Universitat Stuttgart-Hohenheim) wird seit mindestens 28 Jahren im Laboratorium in Dauerzucht gehalten. Die Exposition von P. persimilis-Weibchen auf frisch applizierten, angetrockneten Spritzbelagen auf eingetopften Buschbohnenpflanzen sowie direkte Spritzungen an Jungtieren des Pradators haben gezeigt, das die Zuchtlinie “Koppert” gegenuber dem Fungizid Pyrazophos (Afugan WP 30) sowie gegenuber dem Aphizid Pirimicarb (Pirimor Granulat) resistent war und im Vergleich zu den Zuchtlinien “Hohenheim” und “Littlehampton” gegenuber dem Fungizid Dichlofluanid (Euparen) Toleranz erkennen lies. Die Fungizide Triadimefon (Bayleton spezial), Vinclozolin (Ronilan), Ditalimfos (Frutogard), Dodemorph-acetat (BASF-Mehltaumittel) waren gegenuber allen drei P. persimilis-Zuchtlmien unschadlich. Die Fungizide Bupirimat (Nimrod), Dichlofluanid (Euparen) und Triforin (Saprol) waren gegenuber den Imagines der drei Zuchtlinien unschadlich, gegenuber den Jungtieren der Zuchtlinien “Hohenheim” und “Littlehampton” schwach bis mittelstark schadigend, gegenuber den Jungtieren der Zuchtlinie “Koppert” unschadlich bis schwach schadigend. Die Insektizide Pirimiphos-methyl (Actellic 50) und Pyrethrum + Piperonylbutoxid (Spruzit-Nova-flussig) waren gegenuber den Imagines und Jungtieren aller drei gepruften Zuchtlinien stark schadigend. Die Verwendung der resistenten Zuchtlinie “Koppert” ermoglicht den gleichzeitigen Einsatz von chemischen Pflanzenbehandlungsmitteln zur Bekampfung von Mehltau, Blattlausen und Thripsen ohne Beeintrachtigung des Nutzlings.

Comparison of three different strains of Phytoseiulus persimilis to control Tetranychus urticae on cucumber in glasshouses The effectiveness of three different strains of Phytoseiulus persimilis to control the two-spotted spider mite Tetranychus urticae as well as their susceptibility to pesticides were compared under practical glasshouse cultural procedures in the Federal Republic of Germany. Despite large differences in rearing techniques, no marked differences in the ability of the predator to control the pest in the glasshouses were observed. P. persimilis obtained from the University of Stuttgart-“Hohenheim”, that were kept in laboratory rearings for at least 28 years using detached bean leaves, performed as good as predators in commercial use obtained from the Dutch company “Koppert” & Sohn, Berkel en Rodenrijs or from the Glasshouse Crops Research Institute “Littlehampton”, England. While the “Koppert” strain of P. persimilis was found to be resistant to the fungicide Afugan WP30 (pyrazophos), total mortality of the strain “Hohenheim” was recorded following sprays of this chemical. The use of the resistant “Koppert” strain of P. persimilis allowed the integration of the predator together with Afugan to control T. urticae and Thrips tabaci, taking advantage of the side effect of this preparation on T. tabaci. Spray treatments with Frutogard (ditalimfos), Saprol (triforine), Bayleton spezial (triadimefon), drenches with DuPont Benomyl (benomyl) to control mildew disease, sprays with Euparen (dichlofluanid) against Botrytis disease as well as Pirimor (pirimicarb) against aphids, did not notably affect the populations of the predator in the experiments with all the three strains of P. persimilis and successful control of T. urticae was repeatedly obtained. Zusammenfassung Die Leistung von 3 verschiedenen Zuchtlinien der Raubmilbe Phytoseiulus persimilis Athias-Henriot beim Einsatz gegen Tetranychus urticae Koch an Gurken sowie die Vertraglichkeit des Nutzlings gegenuber Pflanzenschutzmitteln wurde unter in der Bundesrepublik Deutschlandublichen Kulturmasnahmen in kommerziell betriebenen Gewachshausern verglichen. Obwohl die Raubmilben in den Dauerzuchten unterschiedlich gehalten werden, ergaben sich zwischen den einzelnen Zuchtlinien sowohl bei der Vertilgungsleistung als auch bei der Vermehrungsrate keine wesentlichen Abweichungen. Im Vergleich zu Raubmilben der Firma “Koppert” & Sohn (Berkel en Rodenrijs, Niederlande) sowie Raubmilben aus dem Glasshouse Crops Research Institute “Littlehampton” (England) zeigte sich bei P. persimilis aus der Universitat Stuttgart-“Hohen-heim” keine spurbare Leistungsminderung bei der Anwendung im Gewachshaus, obwohl die Tiere dieser Zuchtlinie seit mehr als 28 Jahren im Laboratorium auf abgeschnittenen Bohnenblattern gezuchtet werden. Wahrend P. persimilis der Zuchtlinie “Koppert” gegenuber Afugan WP 30 (Pyrazophos) resistent war, verursachten Spritzbehandlungen mit diesem Fungizid gegenuber Raubmilben der Zuchtlinie “Hohenheim” starke Schaden. Die Anwendung dieser resistenten Raubmilben der Zuchtlinie “Koppert” erlaubte den integrierten Einsatz von P. persimilis und Afugan zur Bekampfung von T. urticae, bei gleichzeitiger Ausnutzung der Nebenwirkung des Praparates gegen T. tabaci. Spritzbehandlungen mit Frutogard (Ditalimfos), Saprol (Triforin), Bayleton spezial (Triadimefon), Benomyl im Giesverfahren zur Bekampfung von Mehltau, Euparen (Dichlofluanid) gegen Botrytis sowie Spritzungen mit Pirimor Granulat zum Auflosen in Wasser (Pirimicarb) gegen Blattlause beeintrachtigten die Vermehrung der Raubmilben in den Versuchen mit allen drei Zuchtlinien von P. persimilis nicht wesentlich und ermoglichten wiederholt die erfolgreiche Bekampfung von T. urticae.

An approach based on solid-phase microextraction-liquid chromatography-mass spectrometry (SPME-LC-MS) has been developed for determining 12 insecticides (bromophos ethyl, chlorpyrifos methyl, chlorpyrifos ethyl, diazinon, fenoxycarb, fonofos, phenthoate, phosalone, pirimiphos methyl, profenofos, pyrazophos, and temephos) in honey. The influence of several parameters on the efficiency of the SPME was systematically investigated. Under optimal conditions, the procedure provided excellent linearity (>0.990), detection and quantification limits (between 0.001 and 0.1 microg g(-1) and between 0.005 and 0.5 microg g(-1), respectively), and precision (

Insecticide resistance monitoring using a Potter precision spray tower with discriminating concentration and log dose probability techniques underpins the Australian insecticide management strategy for Frankliniella occidentalis Pergande. Abamectin, acephate, chlorpyrifos, dichlorvos, dimethoate, endosulfan, fipronil, malathion, methamidophos methidathion, methiocarb, methomyl, pyrazophos and spinosad are recommended for use against F. occidentalis but abamectin, methiocarb and pyrazophos are the only chemicals where insecticide resistance has not been detected. Although not registered, chlorfenapyr was effective against F. occidentalis and should be pursued for that purpose. In contrast, chlorpyrifos, dichlorvos and malathion resistance were detected at low to moderate levels throughout the study period putting their sustainable use for F. occidentalis control in doubt. Although it appears that acephate, dimethoate, endosulfan, fipronil, methamidophos, methidathion and spinosad remain effective, some populations contained a small percentage of thrips that survived exposure to a concentration that killed 100% of the susceptible strain. Subsequent laboratory selection of one such population separately with fipronil and spinosad caused an increase in resistance to these insecticides. These products must now be considered at risk. This is the first report of fipronil or spinosad resistance in populations of F. occidentalis.

Chlorinated hydrocarbons, pyrethroids, organophosphorus, and other miscellaneous pesticides in dried and powdered fruits of Pimpinella anisum were analyzed using two official Association of Official Analytical Chemists methods as a general guidance, and applying Florisil column cleanup. Both methods applied proved to show adequate recovery, repeatability and reproducibility for most of the studied pesticides. But no sole method was able to extract all pesticides residues from real samples. Some pesticides were not recovered sufficiently from the P. anisum fortified samples. The applied methods were not suitable for the extraction of tetramethrin, formothion, pyrazophos and primicarb. Tetramethrin, formothion and pyrazophos showed very low recoveries with the mentioned methods while primicarb was not recovered at all.

A variety of insecticides, acaricides, and fungicides is used in greenhouses to protect plants. As predacious ladybirds are also used to control aphids, it is important to understand the effects of such pesticides on these beneficial insects. We examined the susceptibility to all developmental stages of the multicolored Asian ladybird beetle, Harmonia axyridis (Pallas), to 12 agents: four insecticides, four acaricides and four fungicides. Etofenprox and acetamiprid were highly toxic to most developmental stages, and also in the adult at 200 mg [AI]/L and 40 mg [AI]/L (recommended dosages for aphid control). Thiamethoxam caused knockdown of larvae, pupae, and adults; however, most recovered within 24 h. Imidacloprid, applied at 50 mg [AI]/L, produced LC 50 values of 30.3 and 190.2 mg [AI]/L for 3rd and 4th instars, respectively. Abamectin was highly toxic to eggs, larvae, pupae, and adult ladybirds at rates under 18.4 mg [AI]/L. However, recommended doses of other acaricides were very safe to all stages except for the egg stage of H. axyridis . The fungicide pyrazophos was highly toxic to eggs and larvae at a rate much lower than the recommended dose, while other tested fungicides were not toxic to any of the ladybird stages at rates over 1000 mg [AI]/L. Generally, the 1st and 2nd instars of H. axyridis were very sensitive to most of the tested insecticides and acaricides. Fungicides, on the other hand, were generally harmless to H. axyridis .

The decomposition of the pesticides methidathion and pyrazophos in red and white wine stored under different conditions was studied. Samples of red and white wine were fortified with 3.25 mg/kg of each of the pesticides. One lot was stored under diffuse daylight and the other in a dark closet. Both lots were stored at the same temperature. Their degradation was followed for 80 days. Half-lives of the pesticide methidathion in white and red wine stored in diffuse daylight were 20.1 and 20.0 days, respectively, and 21.1 and 24.2 days for those stored in conditions of darkness. Corresponding half-lives for pyrazophos were 29.7 and 29.1 days for storage in daylight conditions and 31.1 and 34.5 days in darkness conditions. Photodegradation was not found to play any important role in the decomposition of these pesticides under the conditions used.

Aqueous extracts of fruits and leaves of the Chinaberry tree, Melia azedarach L. were tested for their efficacy versus other biotic and synthetic insecticides against the pea leafminer, Liriomyza huidobrensis (Blanchard). The study included field experiments on naturally infested swiss chard, Beta vulgaris var. Cicla L., and greenhouse experiments on artificially infested cucumber, Cucumis sativus L. that were conducted in 1995–96. The other treatments included azadirachtin (0·25%), ultrafine mineral oil, abamectin, cyromazine, imidacloprid, pyrazophos and control. Results of field experiments indicated that Melia fruit extract and the other insecticides significantly lowered the number of larvae per swiss chard plant as compared to the control, at 5 days sampling after second spray or 15 days after first spray, when two consecutive sprays were performed. However, at 10 days after second spray, the fruit extract did not differ significantly from the control, but it was comparable in its effect to the insecticides, except abamectin and cyromazine. In greenhouse experiments, the pea leafminer larvae were found at higher densities on cucumber leaves located at the lower plant part (10–60 cm) compared to other leaf positions. The Melia fruit extract and the other pesticides significantly decreased the number of live larvae per cucumber leaf compared to the control, 10 days after each spray. The fruit extract, abamectin, cyromazine, imidacloprid and pyrazophos lowered the leafminer population significantly compared to the control, throughout the period of the experiments. However, the fruit extract was significantly less effective than these insecticides at the final count, 20 days after second spray. Abamectin and cyromazine consistently showed a significant decrease in number of larvae, in both field and greenhouse experiments. At certain periods of the experiments, Melia extracts were comparable in their efficacy to the tested commercial biorational and synthetic pesticides. Thus, they have a good potential to be used in the management of the pea leafminer. This is the first report for use of M. azedarach against L. huidobrensis.

Erysiphe sp. is a causal agent of powdery mildew on Rhododendron. A novel in vivo method permitting the screening of fungicides on woody plants is described. Eight fungicides were evaluated for activity against Erysiphe sp. using Rhododendron ponticum microplantlets grown in vitro. Pathogen development changed with both the type of fungicidal compound and the concentrations applied. The most active materials were fenpropidin and penconazole, which showed high activity at the lowest concentrations. Six of the compounds performed more effectively than a mixture of bupirimate + triforine (Nimrod T), the standard recommendation for control of this pathogen on Rhododendron. All fungicides affected the sporulation of Erysiphe sp., with propiconazole, pyrazophos and triadimenol causing a significant increase in sporulation at the lowest concentrations. At higher concentrations, sporulation was significantly reduced by all treatments. No phytotoxic effects were detected with any fungicide at any concentration. The growth of plantlets in most treatments showed no significant difference from the untreated controls. The results of the study are discussed in relation to strategies for control and the epidemiology of Erysiphe sp. infecting Rhododendron.

The Carabid Beetle Laboratory Test using Poecilus cupreus (L.) was developed for the assessment of effects of pesticides on beneficial arthropods and is now available as an official guideline published by the BBA and the IOBC for the registration of pesticides. In this contribution some of the experiences in performing the test are summarized. In total, 126 compounds (mainly herbicides) were tested in 190 test runs (including water controls). In this acute laboratory test, the three parameters mortality, behaviour and feeding rate are investigated. Due to experiences with other ecotoxicological tests a one-way Analysis of Variance or ANOVA, followed by a Bonferroni Test, was used for the statistical evaluation of the feeding rates. The results presented here show that a statistical evaluation of the feeding data is possible and that this parameter is useful for the assessment of side-effects of chemicals for these predatory arthropods. In testing the reference substance pyrazophos (formulation : 'Afugan' 294 g litre -1 EC) the mortality varied considerably. It is proposed that at a given value (30%) for effects on the mortality and the feeding rate, a test substance should be tested in a semi-field or field situation.

Effects of 37 fungicides — several of which were mixtures — on adult females of the rove beetle,Aleochara bilineata, were investigated in the laboratory. The pesticides were tested in concentrations equivalent to the highest recommended dosages for practical use. Mortality, egg production and hatch of the eggs were recorded. Most fungicides had no serious effect on any of the parameters measured. Among the morpholine and dithiocarbamate fungicides, several had adverse effects on egg production and/or hatch of the eggs laid. Furthermore, chinomethionate and pyrazophos were found to be toxic at the dosages used. Results are compared to results obtained with other species of beneficial arthropods in the laboratory. The importance of including several species in the assessment of pesticide side effects as well as the importance of measuring sublethal effects are stressed.

The binding of fluorodifen, fenarimol, acifluorfen, 2,4-DES, methyl parathion, paraquat and pyrazophos by alpha, mu and pi class glutathione transferases (GST) was determined by the 2-p-toluidinylnaphthalene-6-sulphonate (TNS) binding fluorescence inhibition technique. Although all the 3 GST classes appear to be capable of binding the pesticides investigated, mu class exhibited somewhat higher affinity than the alpha and pi classes.

The influence of post-treatment temperatures of 5, 10, 17 5, and 25°C on the efficacy of three pesticides, Karate (10 g a i/ha lambda cyhalothnn), Sumicidin 10 (30 g a i/ha fenvalerate), and Afugan (294 g a i/ha pyrazophos), applied to Poecilus cupreus (Coleoptera Carabidae) was investigated in the laboratory The results indicate a negative correlation between the temperature and the effects of all three products With the two pyrethroids Karate and Sumicidin, the recovery period of knocked down beetles and their food consumption showed this negative temperature correlation The reason seems to be a temporarily arrested detoxification of the pyrethroids inside the beetles at reduced temperatures Final mortality seven weeks after application of pyrethroids was unaffected by temperature With the organophosphorus compound pyrazophos final mortality was negatively correlated with temperature Male beetles seemed to be more sensitive than females with all products and temperatures

SummarySixty-five synergists and seven solvents were tested on larvae of a pure breeding pyrethroid resistant strain of Helicoverpa armigera (homozygous for a metabolic detoxification mechanism fully suppressible by piperonyl butoxide (Pbo), presumably via a microsomal monooxygenase system). The methylenedioxyphenyl and acetylenic compounds were the most effective synergists with moderate activity from some organophosphate compounds, particularly the N-alkyl phthalimidomethyl phosphorodithioate, phosmet. All the other compounds tested were either ineffective or only marginally effective including the majority of organophosphates (12 out of 18 tested), pyrethroid analogues, N-alkyls, esterase and glutathione transferase inhibitors, various nitrogen heterocycles, juvenile hormone and analogues, formamidines, organochlorines, anti-oxidants and kojic acid. The most promising synergists indicated for further evaluation were synthetic analogues of Pbo, phosmet, propargite and possibly also fenthion, phosalone, azinphos-ethyl, pyrazophos and kinoprene. All solvents (except dodecane) had no impact on improving kill, indicating that the mode of action of Pbo and the other synergists in this study is principally true biochemical inhibition and not quasi-synergism (improved penetration). Dodecane marginally improved kill in the resistant but not the susceptible strain, indicating some preferential penetration synergism in the resistant strain.A number of trials with Pbo were designed to facilitate the development of this synergist for commercial field use within the Australian IRM strategy. From these, it was found that: 1. A set rate of Pbo should be used, irrespective of the activity of the accompanying pyrethroid. 2. Residual activity of Pbo is poor (less than 50% of initial activity by two days post spray) but that this could be partially overcome by increasing the rate. 3. Straight Pbo applied onto a weathered pyrethroid deposit could restore control but only temporarily and would probably be of little practical field use. 4. No difference in residual activity could be found between the four formulations of Pbo tested. The synthetic analogue PBX was slightly less intrinsically active than the natural product (Pbo) but when tested in the field against Pbo at the same rate, was equivalent in efficacy to both the standard commercial and research Pbo formulations.In order to preserve the long-term effectiveness of Pbo as a pyrethroid synergist within the Australian IRM strategy, an optimal use strategy (based on synergist rotation within the present insecticide rotation scheme) is proposed.

Disposable, ready-to-use cartridges filled with a macroporous diatomaceous material are used to extract in a single step fungicide residues with dichloromethane from aqueous acetone extracts of vegetables. This procedure takes the place of some functions (such as separating funnel partition, drying over anhydrous sodium sulphate and clean-up) usually performed by separate steps in classical schemes. Fourteen fungicides (dichloran, vinclozolin, chlorthalonil, triadimefon, dichlofluanide, procymidone, hexaconazole, captan, folpet, ditalimfos, iprodione, captafol, pyrazophos and fenarimol) were determined using the described procedure with recoveries between 83 and 107% at spiking levels ranging for the different compounds from 0.04 to 0.40 mg/kg. Crops subjected to the described procedure included lettuce, strawberry, apple, yellow pepper and peach, and gave extracts containing a mass of co-extractives between 5 and 30 mg. Compared with classical schemes, the described procedure is simple, less labour intensive, allows parallel handling of several extracts and does not require preparation and maintenance of equipment. Troublesome emulsions such as those frequently observed in separating funnel partitioning do not occur.

The efficacy of an organophosphorus fungicide, pyrazophos, against agromyzids, Ophiomyia phaseoli (Tryon), O. centrosematis (De Meijere) and Melanagromyza sojae (Zehntner) was studied in the laboratory, greenhouse and field tests on three crops: soybean (Glycine max (L.) Merrill), snapbean (Phaseolus vulgaris (L.)) and mungbean (Vigna radiata (L.) Wilczek). Pyrazophos applied as a spray on plants at 0.3 kg a.i./ha controlled M. sojae in soybean as well as the standard recommended insecticide, omethoate, at 0.5 kg a.i./ha. Pyrazophos effectively controlled O. phaseoli on snapbean at 0.1 kg a.i./ha and all three species on mungbean at 0.2 kg a.i./ha. When applied to soil, the fungicide killed agromyzids feeding inside stems of soybean and snapbean. Pyrazophos had contact toxicity to adults of M. sojae and O. phaseoli; all of M. sojae and 55% of O. phaseoli adults died within 24 and 48 h when exposed to 0.01% and 0.05% a.i. pyrazophos film, respectively, on filter paper.

The effects of residues of three commercial pesticides in common use in Europe against cereal pests, on two dominant spider species, a lycosid and a micryphantid, were evaluated in the laboratory. Insecticide assay methods for juvenile and adult hunting and adult web-building, ground-dwelling spiders are described. Results varied with different sprayed substrates and species. Fenvalerate was more toxic than other pesticides and had a longer residual effect on all spiders when tested on moistened sand than on filter paper. Endosulfan was of high initial toxicity on sand, but was more toxic on filter paper to both adults and juveniles ofPardosa spp. Pyrazophos was non-toxic to the spiders tested, regardless of substrate. In general, the lycosids were more affected by pesticides than web-building spiders because of their different life strategies. A sprayed sand substrate matched field conditions better as a method to test the effects of pesticides on ground-dwelling spiders.

Fungicides are widely used in agriculture, and released in large amounts to the environment. Methods used for antifungal susceptibility testing are cumbersome and time-consuming. As a result, very little attention has been paid to including fungal tests in the routine screening of pesticides and there are no reports in the literature of fungicide focussed effects directed analysis (EDA). In addition very little is known on the toxicity of fungicides to environmentally significant fungi. Here we report a rapid microplate-based resorufin fluorescence inhibition bioassay and compare it with a 24 h microplate-based yeast growth inhibition bioassay using eight fungicides. The growth inhibition bioassay was sensitive, giving IC50 and IC90 values comparable to previously reported IC50 or MICs of these fungicides for Saccharomyces cerevisiae and other fungi. The resorufin fluorescence inhibition bioassay was both faster and more sensitive than the growth inhibition bioassay. Inhibitory concentrations obtained just after 30 min of incubation with amphotericin B (AMB) and captan were at least a hundred fold lower than IC50s in the literature for fungi. The fluorescence bioassay showed only a small response to pyrazophos and thiabendazole but these only inhibited growth at high concentrations so this may reflect low sensitivity of S. cerevisiae to these particular fungicides. This bioassay can detect toxic effects of a range of fungicides from different chemical classes with different modes of action. It will be valuable for screening chemical libraries for fungicides and as a biomarker for detecting the effects of fungicides to non-target fungi.

Knowledge of plant disease epidemiology has had increasing impact in the production-based industry of both the developed and developing world. In the last 50 years European agriculture has been associated with a move towards the simplification of cropping systems. Although cereal monoculture is no longer widespread, large areas are still dominated by the production of autumn-sown combinable crops. The effect of this on the biodiversity of the countryside has been accentuated by advances in the control of the weeds and pests — with consequent direct and indirect effects on non-target species and thus on the food chains dependent on them. Fungicides have had far less deleterious environmental impact, though the vermicidal effects of benomyl and the insecticidal properties of pyrazophos gave cause for concern when these were widely used.

The aim was to study the effect of pyrazophos, dinocap, sulphur and fenarimol on the sporulation of fi leucotricha on white shoots of apple. Three treatments were employed (tight cluster, rose bud and 20% open flowering stages) and the number of spores on white shoot leaves assessed. Pyrazophos (3.3/10.5 per mm2) and dinocap (3.7-13.9 mm2) were found to be effective against sporulation, reducing it for more than 80%. For this reason the use of these fungicides is considered most convenient in the early stages of apple growth, especially in the presence of a greater number of white shoots. The use of sulphur in controlling P. leucotricha in the presence of white shoots may be considered less convenient because spore decrease was insignificant (6.4-28.0 per mm2) in relation to the control (14.9-34.7%). The number of spores using fenarimol (8.2-30.5% per mm2) was similar to the control and for this reason its application for controlling P. leucotricha on white shoots may be considered unjustifiable. . U radu je ispitivano antisporulaciono delovanje pirazofosa, dinokapa, sumpora i fenarimola na P. leucotricha, na belim mladarima. Obavljena su tri tretiranja jabuke (zeleni buketić, roze pupoljak i 20% otvorenih cvetova) i posle svakog je utvrđen broj spora na lišću belih mladara. Utvrđeno je da su pirazofos (3.3-10.5 po mm2) i dinokap (3.7-13.9 po mm2) ispoljili dobro anitsporulaciono delovanje, redukujud sporulaciju patogena i preko 80 %- što ih čini pogodnijim za primenu u ranim fenofazama jabuke, posebno u uslovima prisustva većeg broja belih mladara. Sumpor nije doveo do značajnijeg smanjenja broja spora (6.4-28.0 po mm2) u odnosu na kontrolu (14.9-34.7 po mm2) pa je manje podesnim za suzbijanje P. leucotricha u uslovima prisustva većeg broja belih mladara. Posle primene fenarimola broj spora (8,2-30,5 po mm2) je bio sličan kao u kontroli, pa se njegova primena za suzbijanje P. eucotricha u uslovima velike sporulacije patogena na belim mladarima ne može opravdati. .

Residue levels and degradation rates of procymidone residues were studied in green beans grown in a greenhouse. Experiments were planned to also assess the influence of planting density on the behavior of procymidone residues on this type of crop. The study was carried out in four random blocks considering three sub-blocks of different planting densities into each block. Plants were sprayed with Sumisclex 50 WP (1077.5 g of ai/ha) 52 days after the transplantation, and sampling was carried out daily during two different periods of 6 and 5 consecutive days, respectively, around the two harvest days (days 12 and 28 after the treatment). Residue levels of procymidone were determined by using the Luke extraction method and GC-NPD. The average residue levels of procymidone in the overall planting (mean of 12 determinations) were below 2 mg/kg (European maximum residue limit) for all the sampling days, obtaining values of 1.01 +/- 0.55 and 0.37 +/- 0.10 mg/kg, respectively, at the two harvest days. The decline behavior of procymidone residues in the overall plantation and in each block could be described as a pseudo-first-order reaction, obtaining half-life values (t(1/2)) of 10-11 days in all cases. The calculated residue level at the preharvest time (5 days) in the overall plantation was 1.7 mg/kg, but this value in the blocks depended on the block position along the greenhouse and ranged from 2.3 to 0.9 mg/kg. In this work, additional data on the residual behavior of the fungicide pyrazophos in green beans were also obtained.

The association between application rate of a pesticide and its residue in ripe tomatoes was studied. The average residue level (R) of any pesticide in ripe tomatoes remained in quantitative relation to its dose (D), expressed by the following regression equation: R = 0.24 D (mg/kg), where the numerical factor, 0.24, represents the average residue in mg/kg after application of 1 kg active ingredient per hectare with relative standard deviation of 23%. Quantitative association between these 2 factors enables evaluation of greenhouse tomato growers with respect to their observation of Good Agricultural Practice rules and the Plant Protection Act, obligatory in Poland since 1996, and thus may be a reliable basis for the registration of new agrochemicals.

Fungal species were isolated which utilize organophosphate pesticides, viz. phosphorothioic (pirimiphos-methyl and pyrazophos), phosphorodithioic (dimethoate and malathion), phosphonic (lancer) and phosphoric (profenfos) acid derivatives. Pesticide degradation was studied in vitro and in vivo (soil). Aspergillus flavus, A. fumigatus, A. niger, A. sydowii, A. terreus, Emericella nidulans, Fusarium oxysporum and Penicillium chrysogenum were isolated from pesticide-treated wheat straw. The number of A. sydowii colonies was significantly promoted by 1 mmol/L pirimiphos-methyl, pyrazophos, lancer, dimethoate and malathion when used as phosphorus sources and by pirimiphos-methyl and pyrazophos when used as carbon sources. The number of A. flavus colonies increased with 0.5 mmol/L lancer and malathion used as the only carbon sources. A. sydowii, A. niger, A. flavus, E. nidulans and F. oxysporum grew on, and utilized, 5 pesticides as phosphorus source and showed more than 50% mass growth. A. sydowii, A. flavus and F. oxysporum phosphatase hydrolyzed the pesticides suggesting that these species are important pesticide degraders. A. sydowii produced higher amounts of the phosphatase than A. flavus and F. oxysporum. The enzyme was highly active against pyrazophos, lancer and malathion used as the only sources of organic phosphate. A. flavus and A. sydowii phosphatases efficiently hydrolyzed pesticides at 300 ppm in soil, the degradation at 1000 ppm was lower. Mineralization of 1000 ppm pesticides in soil amended with wheat straw was higher than in nonamended soil. All added pesticides except profenfos were degraded within 3 weeks. Lyophilized adapted biomass of A. flavus and A. sydowii could thus be used for field biodegradation of these pesticides.

A method for the determination of organophosphorus pesticides (diazinon, fenitrothion, fenthion, quinalphos, triazophos, phosalon and pyrazophos) in fruit (pears) and fruit juice samples was developed and validated. The samples were diluted with water, extracted by solid-phase microextraction (SPME) and analysed by gas chromatography (GC) using a flame photometric detector in phosphorous mode. Limits of detection of the method for fruit and fruit juice matrices were below 2 micrograms/kg for all pesticides. Relative standard deviations for triplicate analyses of samples fortified at 25 micrograms/kg of each pesticide were not higher than 8.7%. Recovery tests were performed for concentrations between 25 and 250 micrograms/kg. Mean recoveries for each pesticide were all above 75.9% and below 102.6% for juice, and between 70 and 99% for fruit except for pyrazophos in the fruit sample (with mean recovery of 53%). Therefore, the proposed method is applicable in the analysis of pesticides in fruit matrices and the use of the method in routine analysis of pesticide residues is discussed.

Residues of three pesticides (dimethoate, parathion, and pyrazophos) in two artichoke cultivars, Masedu and Spinoso sardo, were investigated. The amount of pesticides in artichokes was greatly affected by the head shape. In the case of the calix-shaped Masedu artichoke, the residues in whole heads at commercial ripening were on average about twice higher than those of the pagoda-shaped Spinoso sardo artichoke. In the heart this ratio was 4 to 42 times greater. Residue decay rates were very fast, mainly owing to the dilution effect due to head growth.

A method has been developed for analysing pesticide residues in whole hops, hop pellets and hop extracts by GC-MS. Five batches of hop pellets containing nine different pesticides (triadimefon, dicofol, mephosfolan, bupirimate, cyhalothrin, tetradifon, endosulfan, pyrazophos and total bisdithiocarbamates) were extracted with liquid CO2. Pesticide concentrations in the original hop pellets and the extracts were determined. The pesticides were concentrated by the extraction process (concentration factor 1.3-8.3), except for the bisdithiocarbamates, which were not extracted. When the same amount of bitterness was added into the brewing process using liquid CO2 extract as opposed to hop pellets, for most of the pesticides proportionately less pesticide was added. However, for two pesticides (dicofol and triadimefon) corrected residue levels were similar to, or in some cases slightly higher than, those in hop pellets.

Le Siganex est un fongicide systémique dont la matière active, le pyrazophos, appartient au groupe des pyrazolopyrimidines (diazines). Son mode d'action est multisite. Il a un mode d'action différent de celui des produits disponibles actuellement. Il peut devenir un moyen de disposer d'une alternative aux inhibiteurs de la biosynthèse des stérols (IBS). Le bilan final de l'essai BA-MR-EXT-199 montrent que le Siganex a une bonne efficacité sur la cercosporiose jaune y compris en période très favorable à la maladie. Toutefois, ses performances et sa rémanence d'action étant sensiblement inférieures à celles des triazoles, il faudra éviter d'employer ce produit en continu sur une longue période

Dans des conditions climatiques très vaforables à la maladie des raies noires (Mycosphaerella fijiensis Morelet) et en présence d'une quantité élevée d'inoculum, nous avons pu mettre en évidence l'efficacité remarquable de 2 triazoles (Diniconazole et San 619F). Ces 2 fongicides ont été appliqués à l'aide d'atomiseurs sur des petites parcelles et comparés au propiconazole; puis sur de grandes surfaces lors de traitements aériens. Les études réalisées au Cameroun conduisent à utiliser en alternance 2 molécules ayant un mode d'action différent et dont l'application est soumise à des conditions climatiques et épidémiologiques bien particulières. Un contrôle de l'apparition éventuelle de races de Mycosphaerella fijiensis résistantes aux triazoles et aux benzimidazoles est réalisé périodiquement sur l'ensemble des plantations bananières. (résumé d'auteur)

Blossom sprays with iprodione, chinomethionat, prochloraz manganese chloride, triadimenol, copper oxychloride, mancozeb, flusilazol, calcium polysulfide, and pyrazophos, applied fortnightly, were evaluated over two seasons (1989-1991) for the control of powdery mildew (Oidium mangiferae), blight (Nattrassia mangiferae), and blossom spot (Alternaria alternata and Colletotrichum gloeosporioides) of mango (Mangifera indica). Blossom sprays with the systemic fungicides flusilazol or pyrazophos resulted in significantly better disease control and consistently higher fruit set and yield than nontreated controls

SUMMARYA series of 24 standardized, replicated field trials comparing 47 fungicidal treatments for the control of spring barley mildew have been analysed. The joint analysis has enabled stronger conclusions to be drawn about the relative efficacy of treatments than examination of individual trials. To increase sensitivity the trials were divided into those with high or low mildew pressure. Under high mildew pressure, the treatments which gave the greatest control of mildew also gave the highest yields. However, within any given treatment the yield response appeared not to be closely related to the degree of mildew control achieved. It is concluded that effective fungicides may have a phytotonic effect as well as a mildew control effect.

Potted and cut flower chrysanthemums (Chrysanthemum morifolium Ramat) were sprayed with 450 mg L−1 a.i. of pyrazophos grown under growth chamber and greenhouse conditions, respectively. A multiresidue method was tested for use on extraction and determination of pyrazophos on chrysanthemums and it was found to give 96% recoveries. Under growth chamber conditions pyrazophos disappeared from potted chrysanthemum plants with a half-life of between 19 and 25 d. On day 0, after allowing the spray to dry, 82% of the residue was removed by washing; at day 35, the amount removed was 43%. Removal by swabbing over the 35 d varied from 4.2% to 7.1%. In six commercial cut flower crops of greenhouse grown chrysanthemums, no evidence of pyrazophos breakdown was observed in plant tissues analyzed between the last spray date and sale of flowers 14 d later. During this period, swabs (wipings) dislodged between 2.7 and 4.6% of surface pyrazophos residue. These data strongly support a recommendation to wear gloves when handling both cut and potted chrysanthemums as workers can spend 30 and 60 h, respectively, handling the crop over each 13- to 15-wk production period.Key words: Pyrazophos, residues, chrysanthemums, greenhouse

SUMMARY Pyrazophos was more effective than dioxanthion against chrysanthemum leaf miner (Phytomyza syngenesiae Hardy) when applied as a mist onto bed-grown plants irrespective of the stage of development of the pest. When pyrazophos was applied at the feeding mark stage no eggs developed but when it was applied at the young mine, mature mine or pupal stages 3–5%, 3-1% or 45-5% reached adulthood. Pyrazophos applied every 17-5 days kept damage levels acceptably low. The potential of pyrazophos within an integrated control programme for chrysanthemum is discussed.

The effects of systemic fungicides on the host-pathogen interface between barley and powdery mildew were studied using cytological methods and specific staining procedures. Propiconazole, etaconazole, bitertanol, triforine, imazalil, nuarimol, tridemorph and fenpropimorph, which are all inhibitors of sterol biosynthesis, stopped growth of the fungus 2 days after application and led to deposits of plant origin around haustoria; these contained polysaccharides, especially callose. This encapsulation resembled the reaction often observed in resistant plants. In contrast, pyrazophos and ethirimol, applied at reduced concentrations, inhibited the fungus at the haustorial stage but did not induce encapsulation. These results suggest that encapsulation is not simply a reaction to the previously damaged fungus, but may be an indirect effect of sterol biosynthesis-inhibiting fungicides on the host metabolism which is elicited by the fungus. The results are discussed in the context of previous observations on the modes of action of these fungicides.

SummarySmall apple plants with sporulating mildew colonies were sprayed with fungicide. The numbers of spores produced after treatment were taken as a measure of the eradicative and anti-sporulant activity of each fungicide. Eight of the materials tested greatly reduced sporulation in the nine days following treatment, but three had very little effect. Bupirimate, pyrazophos, binapacryl and ditalimfos were the most active fungicides tested. An overall rating for the activity of the fungicides against mildew is given.

The insecticide pyrazophos (O-6-ethoxycarbonyl-5-methylpyrazolo[l,5-a]pyrimidin-2-yl O,O-diethyl phosphorothioate), (AfuEanR), fs currently used for the control of leaf mlners (Phytomza atricornis Meigen) on greenhouse-grown chrysanthemums. The recommended rate of application fs a solution containing 450 mg/L (a.f.) which is sprayed until leaves are thoroughly wet and runoff just begins. During the course of this application, which is frequently carried out under restricted work�8 space, garments and protective clothing can readily come in contact with the spray. Previous workers have studied the effects of various factors �8 the removal of organophosphorus insecticides from contaminated clothing. Easley et al (1981, 1982) have reported on the efficiency of various laundering procedures, detergents, and water temperatures in the removal of methyl parathion from denim fabrics. Laughlin et al (1985) studied the influence of different formulations of methyl parathion on the removal of the insecticide using conventional laundering practices. This note describes a study which was intended to determine the efflciency of household laundering in removing pyrazophos from contamlnated fabrlc. MATERIALSANDMETHODS Cotton/~olyester coverall fabric was eut into lOcm x 20cm strips (200 cm ~) and the edges were machine-stitched to prevent fraying. Four swatches were arranged into layers and placed randomly onto newspaper laid out on the bed of a custom-built cabinet sprayer; the sprayer consisted of an overhead mobile liter container fitted with a nozzle and pressurized by an air pump. The newspaper served to soak up spray around the target fabrics. To simulate drlft ~nd spill situstions, the fabric was sprayed at rates of 48 ml/m ~ and 240 ml/m A respectlvely, uslng a solution of 450 mg pyrazophos per liter of water; these applications were equivalent.to absolute levels of 432 ~g and 2160 ~g of pyrazophos per 200 cmZ-swatch. The fabric was allowed to dry for 8 hours at amblent temperature before being laundered. AI1 treatments were replicated four times. Send reprint requests to H.E. Braun at the above address.

SUMMARY The insecticidal properties of the foliar fungicide pyrazophos were investigated in autumn- and spring-sown barley crops using several methods to estimate the density of non-target arthropods and by using manipulative experiments. In autumn-sown crops, pyrazophos significantly reduced densities of cereal aphid natural enemies relative to pre-treatment levels compared to areas of crop that were left unsprayed. These significant differences persisted in most groups for over 45 days after treatment. Groups most affected were aphid-specific predators, polyphagous predators, (Carabidae, Staphylinidae but not Araneae) and parasitoids. Insects known to be preferred food items of wild gamebird chicks and other non-target groups such as the Collembola were also significantly reduced in density on plots sprayed with pyrazophos, the effects again persisting for over 45 days. Densities of beneficial and non-target insects were also reduced in plots of spring barley sprayed with pyrazophos. However, the experimental design meant that levels of reductions were not significant for most arthropod groups. Removal of prey items (Drosophila pupae) placed in sprayed and unsprayed spring barley plots showed that the proportion predated was significantly lower on pyrazophos-treated plots compared to those remaining unsprayed, the difference persisting for at least 7 wk after treatment. Removal of cereal aphids from colonies introduced to sprayed and unsprayed plots was also significantly lower on plots treated with pyrazophos. Difficulties of data interpretation associated with experimental design are discussed together with the consequences of the use of broad-spectrum pesticides in I.P.M. programmes in cereals.