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Several crops of agronomic interest depend on bees' pollination, and Apis mellifera L (Hymanoptera: Apidae) is the most studied direct pollinator. Nevertheless, the use of pesticides in agricultural environments is common, including fungicides. Studies that seek to evaluate the effects of fungicides on the hypopharyngeal glands of bees, the site of royal jelly synthesis, are lacking. Thus, this work aimed to evaluate the effect of field doses of fungicides (Captan SC® and Zignal®), alone or in mixture, on the hypopharyngeal glands and their subsequent effect on the strength of hives. The evaluations were carried out under field conditions in three hives per treatment. For a period of one month, bee hives received feed containing sugar syrup, pollen and 1.2 mL of Zignal® and 3 mL of Captan SC® in the isolated treatments and 4.2 mL in the mixture. The action of fungicides on the hypopharyngeal glands was determined by transmission electron microscopy analysis in bees 7 and 15 days old, collected in the hives one month after exposure to fungicides. The strength of the hives was evaluated for six months based on the number of frames with adult bees, open and closed brood, and stored food. The results indicate that fungicides promote early degeneration of the rough endoplasmic reticulum and morphological and structural changes in mitochondria. In addition, a reduction in adult population, open and closed breeding and food stock was observed. More pronounced damage occurred when bees were exposed to the mixture of fungicides. Overall, it can be concluded that the presence of fungicides in bee diets promotes harm accentuated over time and compromises the survival of hives. It will be worth estimating the fungicide effects of the queen development and on the colony heath.

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Global banana production is currently challenged by Panama disease, caused by Fusarium oxysporum f.sp. cubense Tropical Race 4 (FocTR4). There are no effective fungicide-based strategies to control this soil-borne pathogen. This could be due to insensitivity of the pathogen to fungicides and/or soil application per se. Here, we test the effect of 12 single-site and 9 multi-site fungicides against FocTR4 and Foc Race1 (FocR1) in quantitative colony growth, and cell survival assays in purified FocTR4 macroconidia, microconidia and chlamydospores. We demonstrate that these FocTR4 morphotypes all cause Panama disease in bananas. These experiments reveal innate resistance of FocTR4 to all single-site fungicides, with neither azoles, nor succinate dehydrogenase inhibitors (SDHIs), strobilurins or benzimidazoles killing these spore forms. We show in fungicide-treated hyphae that this innate resistance occurs in a subpopulation of "persister" cells and is not genetically inherited. FocTR4 persisters respond to 3 µg ml-1 azoles or 1000 µg ml-1 strobilurins or SDHIs by strong up-regulation of genes encoding target enzymes (up to 660-fold), genes for putative efflux pumps and transporters (up to 230-fold) and xenobiotic detoxification enzymes (up to 200-fold). Comparison of gene expression in FocTR4 and Zymoseptoria tritici, grown under identical conditions, reveals that this response is only observed in FocTR4. In contrast, FocTR4 shows little innate resistance to most multi-site fungicides. However, quantitative virulence assays, in soil-grown bananas, reveals that only captan (20 µg ml-1) and all lipophilic cations (200 µg ml-1) suppress Panama disease effectively. These fungicides could help protect bananas from future yield losses by FocTR4.

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The aim of this work was to isolate fungal strains from phytotoxic agricultural soils, screen them, categorize the most tolerant fungi to three fungicides, and identify them by a molecular approach. In this study, 28 fungal strains were isolated from phytotoxic agricultural soil with intensive use of pesticides. The capacity of fungi to resist and degrade different concentrations of carbendazim, captan, and zineb was determined by an exploratory multivariate analysis. Actinomucor elegans LBM 239 was identified as the most tolerant fungus to these fungicides, degrading a 86.62% of carbendazim after 7 days of treatment. In conclusion, A. elegans LBM 239 demonstrated the highest tolerance and capacity to biodegrade carbendazim, becoming a potential candidate for bioremediation of contaminated soils with carbendazim, captan, or zineb.

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Captan is one of the most widely used broad-spectrum fungicide applied to control several early and late diseases of grapes, apples, and other fruits and vegetables, and as other phthalimide fungicides is defined as a multisite compound with thiol-reactivity. Captan can affect non-target organisms as yeasts, modifying microbial populations and fermentation processes. In this study, we asked whether Captan thiol-reactivity and other mechanisms are involved in acute Captan-induced cell death on aerobic growing Saccharomyces cerevisiae. Thus for, we analyze cellular protein and non-protein thiols, cell membrane integrity, reactive oxygen species accumulation, phosphatidylserine externalization, and apoptotic mutants behavior. The results showed that when submitted to acute Captan treatment most cells lost their membrane integrity and died by necrosis due to Captan reaction with thiols. However, part of the cells, even maintaining their membrane integrity, lost their culture ability. These cells showed an apoptotic behavior that may be the result of non-protein thiol depletion and consequent increase of reactive oxygen species (ROS). ROS accumulation triggers a metacaspase-dependent apoptotic cascade, as shown by the higher viability of the yca1-deleted mutant. Together, necrosis and apoptosis are responsible for the high mortality detected after acute Captan treatment of aerobically growing cells of S. cerevisiae.

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This paper describes the antinociceptive effects of tetrahydrophthalimides and related compounds in mice. Twenty compounds were obtained by the reaction of cis-1,2,3,6-tetrahydrophthalic anhydride with appropriate amines, dehydration, and addition to the imidic double bond. They were analyzed in the writhing test at 10 mg/kg given intraperitoneally. The most active compound 2-benzyl-5-morpholin-4-yl-hexahydroisoindole-1,3-dione (19) was studied on formalin, capsaicin, glutamate and hot plate models. The antinociceptive activity demonstrated by some studied compounds is promising, and some of them were more active than acetylsalicylic acid and paracetamol used as reference drugs in writhing tests in mice. Compound 19 was about 5-fold more potent than the reference drugs, being also effective by oral route and against the inflammatory response in the formalin test. The results suggest that compound 19 could be used as a model to obtain new and more potent antinociceptive agents. It exhibits an interesting antinociceptive profile, and does not interact with opioid systems.

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An analytical method has been developed that can be used to determine the potential dermal exposure (PDE) of workers to the pesticide captan in small-scale horticultural production units. The methodology is based on the whole body dosimetry technique, using a cotton coverall and cotton gloves as sampling media, with protective clothing worn beneath the cotton media to protect the operator. The quantitative determination of captan was done by gas chromatography-electron capture detector (GC-ECD), with the analytical method validated by measuring limits of detection and quantification, linear ranges, sample recovery and precision. Special emphasis is placed on factors that affected the stability of captan during chromatographic determination. The data generated for potential dermal exposure are presented separately for mixing/loading and application activities. These data are compared with values obtained with visible tracers using a similar field technique. Margin of safety (MOS) values are also calculated for the agricultural procedures studied.

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The effect of fungicide captan on growth and nitrogenase activity of Azospirillum brasilense Cd was studied in pure cultures and in association with foxtail millet (Setaria italica) cultivar Carapé under laboratory conditions. The 8 h growth in rotary shaker of A. brasilense was inhibited with 1 mg/l pure captan; however, after 4 days the differences diminished compared with the control without captan. Nitrogenase activity was affected with 10 mg/l but the differences were negligible after 48 h of growth. Root dry weight of inoculated plants was diminished by the treatment of foxtail millet cv. Carapé with captan. Inoculation with A. brasilense Cd increased shoot dry weight, but differences were significant only with respect to the control but not in relation to captan treatments.

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Resíduos de captan e clorotalonil foram quantificados em morangos "in natura" após três e sete dias de estocagem em geladeira -5oC . As amostras analisadas foram coletadas na CEASA de Campinas e também obtidas após cultivo em estaçäo experimental

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Duas espécies de Oligochaetas edáficos foram avaliadas para determinar a CL50 através do método "ARTISOL" adaptado, utilizando-se quatro formulaçöes distintas do fungicida CAPTAN. Os resultados obtidos indicaram variabilidade entre as espécies, demonstrando que agentes químicos podem afetar diferentemente organismos do mesmo grupo. Portanto, a utilizaçäo de grupos representativos da pedofauna em biotestes confirma a necessidade de aprimorar novas técnicas, com o objetivo de fornecer resultados efetivos que possibilitem entender melhor o grau de toxicidade dos químicos.

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