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Bulk deposition of pesticide mixtures in a Canadian prairie city and the influence of soil temperature fluctuations on 17β-estradiol mineralizationAndronak, Lindsey Amy 16 August 2013 (has links)
Tests were conducted for 71 pesticides in weekly bulk (wet + dry) deposition samples collected from May 25 to September 21 over two years at two sites in the City of Winnipeg, Canada. Twenty-one pesticides and their metabolites were detected in this study and 99% of samples collected contained mixtures of two or more pesticides. Malathion and glyphosate were the largest contributors to bulk deposition in 2010 and 2011, respectively. A second study examined the mineralization of 2,4-D and 17β-estradiol using a novel in-field soil microcosm study and a series of laboratory experiments under different temperature incubations. Results indicated that temperature fluctuations do not greatly affect the amount or rate of mineralization relative to the traditionally constant laboratory incubations of 20°C; however long-term freezing of soil reduced potential mineralization over time. This research advances scientific knowledge of agri-chemical fate and provides data for strengthening current environmental policy analysis in Canada.
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Bulk deposition of pesticide mixtures in a Canadian prairie city and the influence of soil temperature fluctuations on 17β-estradiol mineralizationAndronak, Lindsey Amy 16 August 2013 (has links)
Tests were conducted for 71 pesticides in weekly bulk (wet + dry) deposition samples collected from May 25 to September 21 over two years at two sites in the City of Winnipeg, Canada. Twenty-one pesticides and their metabolites were detected in this study and 99% of samples collected contained mixtures of two or more pesticides. Malathion and glyphosate were the largest contributors to bulk deposition in 2010 and 2011, respectively. A second study examined the mineralization of 2,4-D and 17β-estradiol using a novel in-field soil microcosm study and a series of laboratory experiments under different temperature incubations. Results indicated that temperature fluctuations do not greatly affect the amount or rate of mineralization relative to the traditionally constant laboratory incubations of 20°C; however long-term freezing of soil reduced potential mineralization over time. This research advances scientific knowledge of agri-chemical fate and provides data for strengthening current environmental policy analysis in Canada.
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The Effects of the Glyphosate-based Herbicide WeatherMax on Sexual Differentiation and Growth in the Wood Frog (Lithobates sylvaticus)Robertson, Courtney 20 February 2013 (has links)
Glyphosate-based herbicides are the dominant pesticide on the market and are utilized worldwide in both the agricultural and forestry industries. Their prevalence comes at a time when concern over the potential effects of pesticide application in amphibian spawning grounds is growing. The primary goal of this thesis was to determine if the glyphosate-based herbicide WeatherMax® has the potential to disrupt sexual differentiation and growth in the wood frog (Lithobates sylvaticus) in a pulse exposure at the predicted maximal environmental concentration (PMEC) of 2.88 mg acid equivalent per liter. This was carried out in laboratory, mesocosm and in-situ field exposures, in an attempt to determine how a potential disruption might vary between experimental environments. In this study, tadpoles from three split-wetlands targeted at the PMEC for WeatherMax were found to display no significant change in survival or growth, however gene expression of several genes involved in steroidogenesis during sexual differentiation (cyp19, cyp17, star, foxl2) were found to be affected. The effects on these genes appeared to be dependant on the exposure concentration of WeatherMax in each wetland, which varied even though all three wetlands were meant to target the PMEC. The wetland that was measured as having the highest herbicide concentration (PMEC 13) was found to have a female biased sex ratio. The results found in the field varied from those found in the more artificial exposures. In the laboratory the PMEC of WeatherMax experienced complete mortality, whereas in the mesocosms survival was not significantly affected. Sex ratios were unaffected in the laboratory, however at the PMEC there was a significant male bias in the mesocosms. The discrepancies in the results obtained from the different exposure types highlights the importance of real world exposures. That the same concentration that caused complete mortality in the laboratory caused sublethal effects in the field is of importance as it denotes that these endpoints may not be easily investigated in these synthetic exposures. This project is a part of the Long Term Experimental Wetlands Area (LEWA) and contributes to the body of information amassed therein on the impact of a glyphosate-based herbicide on amphibians in a wetland ecosystem.
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Influence of soil properties and organic pesticides om soil microbial metabolism /Schnürer, Ylva, January 2006 (has links) (PDF)
Diss. (sammanfattning) Umeå : Sveriges lantbruksuniv., 2007. / Härtill 3 uppsatser.
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Impacts of an herbicide and predator cues on a generalist predator in agricultural systemsWrinn, Kerri M. January 2010 (has links)
Title from second page of PDF document. Includes bibliographical references.
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Efeito de doses letais e subletais de herbicidas sobre a mortalidade e alterações comportamentais de Apis mellifera L.Lunardi, Juliana Sartori. January 2018 (has links)
Orientador: Percília Cardoso Giaquinto / Resumo: As abelhas têm grande importância na polinização; no entanto, o desaparecimento e morte de colônias de Apis mellifera Linnaeus, 1758 (Hymenoptera: Apidae) têm aumentado em várias regiões do mundo, prejudicando a sobrevivência da espécie e a estrutura dos ecossistemas. O uso de agrotóxicos em cultivos agrícolas vem sendo apontado como um dos fatores responsáveis pela intensificação do desaparecimento das abelhas. No presente estudo, avaliou-se a toxicidade, as alterações comportamentais e motoras de abelhas campeiras de A. mellifera expostas aos herbicidas 2,4-D e glifosato, isolados ou associados, por testes de ingestão e contato. Para determinação da dose letal (DL50) foi analisada a mortalidade de abelhas expostas a diferentes doses dos herbicidas por contato e ingestão por 24 horas. A atividade motora das abelhas expostas aos herbicidas glifosato, 2,4-D e associação de ambos foi avaliada 4 e 24 horas após sua exposição utilizando caixa de observação comportamental. As DL50 encontradas dos herbicidas glifosato e 2,4-D foram respectivamente: 273,93 e 127,70 µg/abelha para ingestão e 255,73 e 97,09 µg/abelha para contato. As doses subletais dos herbicidas glifosato e 2,4-D foram, respectivamente: 5,47 e 2,55 µg/abelha para ingestão e 5,11 e 1,94 µg/abelha para contato. A dose letal de 4 horas e subletal de 24 horas foram altamente tóxicas para as abelhas causando alterações locomotoras, as quais em campo podem influenciar o forrageamento das campeiras. Dos testes de doses sub... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Bees are very important for pollination, however, disappearance and death of Apis mellifera hives in many regions of the world has increased, damaging the species survival and ecosystems maintenance. The use of herbicides in agricultural crops has been accused as one of the factors responsible for this disappearance. This study aimed to evaluate the toxicity, behavioral and motor abnormalities on foraging honey bees Apis mellifera exposed to 2,4-D and glyphosate alone and combined. To determine the lethal dose (LD50), bees were exposed to different herbicides doses by contact or ingestion and mortality was analyzed. After 24 hours, the mortality results were analyzed. The glyphosate and 2,4-D LD50 found were, respectively: 273,93 and 127,70 μg/bee for ingestion and 255,73 and 97,09 μg/bee for contact. The sublethal doses for glyphosate and 2,4-D were, respectively: 5,47 and 2,55 μg/bee for ingestion and 5,11 and 1,94 μg/bee for contact. The bee’s motor activity was assessed 4 and 24 hours after herbicides and combination exposure, using a behavioral observation box. The 24 hours lethal and sublethal doses were highly toxic to bees causing locomotors changes, which in the field can influence the bees foraging activity. Only the 4h sublethal herbicide association test showed additive effect, however this fact deserves attention because when carried to the colony, the herbicides can influence other bees behavior and cause weakening or even death of the hive. / Mestre
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Classificação e eficiência de materiais e de vestimentas de proteção no trabalho com agrotóxico /Francischini, Letícia Ane Sizuki Nociti. January 2009 (has links)
Orientador: Joaquim Gonçalves Machado Neto / Banca: Maurício Leite de Oliveira / Banca: Manoel Lima de Menezes / Banca: Núbia Maria Correia / Banca: Claudinei da Cruz / Resumo: No Brasil, os CAs são emitidos por meio de um termo de responsabilidade técnica, sem avaliação de eficiência e vida útil. Os objetivos deste trabalho foram: 1) Quantificar a repelência, retenção e penetração em sete materiais hidrorrepelentes para o fungicida tiofanato metílico e em oito para herbicida glifosato; 2) Classificar os materiais hidrorrepelentes quanto à repelência e à penetração do fungicida tiofanato metílico e do herbicida glifosato; 3) Quantificar a permeação do fungicida tiofanato metílico e do herbicida glifosato em seis materiais impermeáveis; 4) Classificar os materiais impermeáveis quanto à permeação do fungicida tiofanato metílico e do herbicida glifosato; 5) Avaliar a eficiência de dois conjuntos hidrorrepelentes sem uso e ao longo de 30 usos e lavagens no controle da exposição dérmica de tratoristas em pulverizações de agrotóxicos em cultura de citros e de aplicadores de herbicidas em pósemergência em cana-de-açúcar. Quanto a repelência ao tiofanato metílico na formulação diluída, dos sete materiais avaliados, apenas um foi classificado como 2 pela ISO 16602 e na formulação pura todos foram classificados como 2 ou 3. Para a penetração todos foram classificados como 3. Para o glifosato os oito materiais avaliados foram classificados como 3 nas formulações diluída e pura quanto a repelência e penetração. Os seis materiais foram menos permeáveis ao tiofanato metílico na formulação diluída do que na pura. Para o glifosato diluído o material pvc foi permeável, o tychem SL e QC foram impermeáveis e o polipropileno laminado, aluminizado e tyvek foram permeáveis. Os dois conjuntos hidrorrepelentes avaliados no campo, sem uso e com 5, 10, 20 e 30 usos e lavagens controlaram mais de 90% da exposição dérmica dos tratoristas de pulverizador de arrasto tratorizado de jato transportado e dos aplicadores usando pulverizadores costais manuais. / Abstract: In Brazil, CAs are issued through a responsible technical term, without its efficient evaluation or lifespan. Thus, the objectives of this study were: 1) Quatify the repellency, the retention and the penetration in seven hydrorrepellent materials to methyl thiophanate fungicide and eight to glyphosate herbicide; 2) Classify the hidrorrepellent materials as for the repellency and the penetration of the methyl thiophanate fungicide and the glyphosate herbicide; 3) Quantify the permeability of the methyl thiophanate fungicide and the glyphosate herbicide in six impermeable materials; 4) Classify the impermeable materials as for the permeability of the methyl thiophanate fungicide and the glyphosate herbicide; 5) The evaluate the efficiency of the two-set protecting hydrorrepellent without use clothing and through 30 wearings and washings to control the dermal exposure of the orchard sprayer tractor driving of crop protection products in citrus crop and back pack sprayer of herbicides in post-emergency sugar cane crop. As for the repellency to the methyl thiophanate in diluted concentration, only one among the seven evaluated tissues, was classified as and in pure concentration all of them were evaluated as 2 or 3. All of them were classified as 3 for penetration. The eight tissues were classified as 3 in diluted and pure concentrations of glyphosate as for the repellency and penetration. The six evaluated materials were less permeable to methyl thiophanate diluted concentration than to the pure one. The pvc material was permeable to the diluted glyphosate, the tychem SL an QC were impermeable while the polypropylene rods, the aluminized and the tyvek were permeable. The two valuated hydrorrepellent sets in field, unused clothing and after 5, 10, 20 and 30 wearings and washing controlled more than 90% of dermal exposure of the orchard sprayer tractor driving and the back pack sprayers. / Doutor
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Intervalos de chuva na eficiência de herbicidas aplicados em pós-emergência /Souza, Guilherme Sasso Ferreira de, 1987. January 2011 (has links)
Orientador: Dagoberto Martins / Banca: Pedro Luis da Costa Aguiar Alves / Banca: Roberto Andreani Junior / Resumo: O objetivo do presente trabalho foi avaliar a influência de diferentes intervalos de chuva na eficiência de herbicidas aplicados em pós-emergência em quatro espécies de plantas daninhas: Ipomoea grandifolia, Senna obtusifolia, Brachiaria decumbens e Brachiaria plantaginea. O experimento foi conduzido em condições de casa-de-vegetação com uma planta por vaso, com capacidade de 2,5 L. O delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições, disposto em um esquema fatorial 7x8 (sete tratamentos químicos e oito intervalos de chuva) para as espécies dicotiledôneas e 6x8 (seis tratamentos herbicidas e oito intervalos de chuva) para as monocotiledôneas. Os tratamentos testados foram: glyphosate em cinco formulações comerciais (Roundup Original, Roundup WG, Roundup Transorb, Roundup Transorb R e Roundup Ultra) a 1.080 g e.a. ha-1, amonio-glufosinate a 400 g i.a. ha-1 e, apenas para as espécies dicotiledôneas utilizou-se o tratamento com 2,4-D a 1.000 g e.a. ha-1. A simulação de chuva de 20 mm foi realizada em oito intervalos de tempo após a aplicação dos herbicidas (15‟, 30‟, 1h, 2h, 4h, 6h, 8h e sem chuva). Foram realizadas avaliações visuais de controle das plantas aos 3, 7, 14, 21, 28 e 35 dias após a aplicação (DAA) para I. grandifolia,aos 3, 7, 14, 21 e 28 DAA para S. obtusifolia, aos 3, 7, 14 e 21 DAA para B. decumbens e aos 3, 7 e 14 DAA para B. plantaginea. Ao final do período de avaliação de cada espécie determinou-se a massa seca das plantas. Os resultados foram submetidos à análise de variância pelo Teste "F" e as médias dos tratamentos comparadas pelo teste de Tukey a 5% de probabilidade. Para plantas de I. grandifolia a ocorrência de chuvas após 15 minutos da aplicação do herbicida 2,4-D não afetou sua eficiência de controle, já os herbicidas amonio-glufosinate e glyphosate, em todas suas ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The aim of this study was to evaluate the influence of different intervals of rain in the efficiency of herbicides applied post-emergence in four weed species: Ipomoea grandifolia, Senna obtusifolia, Brachiaria decumbens and Brachiaria plantaginea. The experiment was conducted in conditions of green-house with one plant per pot, with a capacity of 2.5 L. The experiment was a completely randomized design with four replications, arranged in a 7x8 factorial arrangement (seven chemical treatments and eight intervals of rain) for dicotyledons and 6x8 (six and eight herbicide treatments rain intervals) for monocotyledons. The treatments were: glyphosate in five formulations (Roundup Original, Roundup WG, Transorb Roundup, Roundup and Roundup Ultra Transorb R) to 1080 g ae ha-1 ammonium-glufosinate at 400 g ai ha-1, and only for dicot species, we used treatment with 2,4-D and 1,000 g ha-1. The simulated rainfall of 20 mm was accomplished in eight intervals of time after herbicide application (15', 30', 1h, 2h, 4h, 6h, 8h and no rain). Visual evaluations of weed control at 3, 7, 14, 21, 28 and 35 days after application (DAA) for I. grandifolia, 3, 7, 14, 21 and 28 DAA for S. obtusifolia, 3, 7, 14 and 21 DAA for B. decumbens and at 3, 7 and 14 DAA for B. plantaginea. At the end of the trial period of each species determined the dry mass of plants. The results were subjected to analysis of variance test by "F" and the means were compared by Tukey test at 5% probability. For plants I. grandifolia to rainfall after 15 minutes of application of 2,4-D did not affect the efficiency of control because the herbicides glufosinate and glyphosate-ammonium, in all its formulations tested showed reduced efficiency of control when the occurrence of rainfall up to 8 hours after herbicide application and, with the exception of Roundup Original, all herbicides provided greater than 50% reductions in dry mass of ... (Complete abstract click electronic access below) / Mestre
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Desenvolvimento de plântulas de soja em função da dessecação das plantas e do tratamento das sementes /Toledo, Mariana Zampar, 1982- January 2011 (has links)
Orientador: Cláudio Cavariani / Banca: Edvaldo Aparecido Amaral da Silva / Banca: Maria Laene Moreira de Carvalho / Banca: José de Barros França Neto / Barnca: Ana Dionisia da Luz Coelho Novembre / Resumo: Esta pesquisa foi realizada com o objetivo de avaliar a germinação das sementes e o desenvolvimento de plântulas de soja em função do tratamento químico das sementes, de diferentes níveis de vigor inicial, com fungicidas, inseticidas, micronutrientes e bioestimulante, produzidas com e sem dessecação das plantas em pré-colheita com glyphosate. A primeira etapa da pesquisa constou da produção de sementes da cultivar Conquista com diferentes níveis de vigor inicial, com e sem dessecação das plantas. O delineamento experimental foi blocos ao acaso, com quatro repetições, em esquema de parcelas subsubdivididas. As parcelas principais foram definidas por duas épocas de semeadura (novembro e dezembro de 2008) e as subparcelas pela realização ou não da dessecação das plantas em pré-colheita com glyphosate na dose de 2,0 L ha-1, no estágio R7. As sementes foram colhidas em três etapas para cada uma das combinações de tratamentos no campo, quais sejam 1, 7 e 14 dias após a maturidade fisiológica, constituindo as subsubparcelas. Na etapa seguinte avaliou-se a qualidade das sementes colhidas, mediante testes de germinação e de vigor, para a determinação dos diferentes níveis de vigor. As sementes foram, então, tratadas com fungicidas, inseticidas, micronutrientes e um bioestimulante para posterior avaliação da germinação e do desenvolvimento das plântulas. Por fim, as sementes armazenadas, após o tratamento químico, foram avaliadas quanto às características das plântulas por meio de análise computadorizada de imagens (Seed Vigor Imaging System - SVIS®). Para a análise estatística, o delineamento experimental utilizado foi o inteiramente casualizado, com quatro repetições. Os dados de caracterização da qualidade das sementes após a colheita foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey (p 0,05) ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work had the objective of evaluating soybean germination and seedling development affected by chemical treatment of seeds, with different vigor levels, with fungicides, insecticides, micronutrients and biostimulant, produced with and without preharvest desiccation with glyphosate. The first stage of this research was the production of soybean seeds, cultivar Conquista, with different levels of initial vigor, both with and without plant desiccation. Main plots consisted of two sowing times (November and December of 2008) combined with and without pre-harvest desiccation of plants with glyphosate at the dose 2,0 L ha-1, at R7, which were the subplots. Seeds of each subplot were harvested at three times, i.e., 1, 7 and 14 days after physiological maturity. Afterwards, seed quality was evaluated by germination and vigor tests to determine vigor levels. Then, seeds were treated with fungicides, insecticides, micronutrients and a biostimulant to evaluate germination and seedling development. Finally, the characeristics of seedlings produced by the stored seeds, treated and non-treated, were evaluated by an image system (Seed Vigor Imaging System - SVIS®), at The Ohio State University, Department of Horticulture and Crop Science, Columbus, Ohio, U.S.A. For statistical analysis, the experimental design was the completely randomized, with four replications. Seed quality data evaluated right after harvest was submitted to variance analysis and means were compared by the Tukey test (p 0.05), separately for each desiccation treatment. After chemical treatment, means were compared by the Tukey test (p 0,05) and analyzed as a factorial 2 x 6 x 8 (with and without pre-harvest desiccation x vigor levels x product) for fungicides, 2 x 6 x 2 for insecticides and 2 x 6 x 3 for micronutrients and the biostimulant. Dunnett test (p 0,05) was applied to compare each mean value with the control, without ... (Complete abstract click electronic access below) / Doutor
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Efeito do glyphosate no crescimento e na morfoanatomia de eucalipto / Effect of glyphosate on eucalypt growth and morphoanatomySantos, Leonardo David Tuffi 30 July 2004 (has links)
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Previous issue date: 2004-07-30 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O eucalipto é a essência florestal mais utilizada nos programas de reflorestamento no Brasil, tendo importante papel social e econômico. Diante da importância do uso do glyphosate para o estabelecimento da cultura do eucalipto no campo e da necessidade de conhecer os reais efeitos deste herbicida sobre a cultura e seu agrossistema, foram realizados três experimentos,para avaliar: o crescimento e a morfoanatomia foliar de plantas de eucalipto submetidas à deriva simulada de glyphosate por meio se subdoses (0, 3, 6, 12 e 24% da dose de 1440 g ha-1); a exsudação radicular do glyphosate por Brachiaria decumbens e seus efeitos sobre plantas de eucalipto cultivadas em solo e em solução nutritiva; a respiração microbiana, sob diferentes manejos, com o herbicida glyphosate; e a tolerância de diferentes clones de eucalipto à deriva do glyphosate. As injúrias provocadas pela deriva do glyphosate foram proporcionais ao aumento das subdoses, sendo representadas por murcha, clorose progredindo para necrose, enrolamento das folhas e morte dos ponteiros. Nas plantas tratadas com as maiores subdoses, observou-se, na estrutura anatômica, áreas necrosadas, hiperplasia das células do parênquima clorofiliano e da epiderme, proliferação celular, acúmulo de compostos fenólicos e variação na espessura e na área dos tecidos foliares. Nos experimentos instalados para o estudo da exsudação do glyphosate, não houve sintomas de toxidez nas plantas de eucalipto cultivadas em sistema hidropônico e no solo, não podendo ser comprovada, pela metodologia utilizada, a exsudação do herbicida pelas plantas de braquiária. Entretanto, o uso do glyphosate, no manejo da braquiária, estimulou a atividade microbiana, principalmente no solo arenoso. Houve diferença de tolerância ao glyphosate pelos clones de eucalipto, sendo E. grandis mais sensível ao herbicida que E. urograndis e E. urophylla. Na estrutura anatômica dos diferentes clones, não foi verificada diferença marcante que possa explicar a tolerância diferencial encontrada. / Eucalypt is the most used forest essence in reforestation programs in Brazil, with an important social and economical role. To establish eucalypt crops in the field, glyphosate and knowledge on the real effects of this herbicide on the crop and its agrosystem are of great importance. Three experiments were therefore carried out to evaluate: leaf growth and morphoanatomy of eucalypt plants subjected to simulated glyphosate drift under subdoses (0, 3, 6, 12, and 24% of a rate of 1440 g ha-1); root exudation of glyphosate by Brachiaria decumbens and the effects on eucalypt plants cultivated in soil and in nutritive solution; the microbial respiration under different managements with the herbicide glyphosate; and the tolerance of different eucalypt clones to glyphosate drift. The injuries caused by the drift of the glyphosate were proportional to the increase of the subdoses, expressed by wilting, chlorosis and eventually necrosis, curling up of the leaves and death of the shoot apical. The anatomical structure of the plants treated with the highest subdoses presented necrotic areas, hyperplasia of the chlorophyllous parenchyma and epidermis cells, cell proliferation, accumulation of phenolic compounds, and variations in thickness and area of leaf tissues. In the experiments set up to study the glyphosate exudation, there were no toxicity symptoms in the eucalypt plants cultivated in hydroponic system and in the soil. No exudation of the herbicide by brachiaria plants was verified by the applied methodology. However, the use of glyphosate in the brachiaria management stimulated the microbial activity, mainly in sandy soil. The eucalypt clones differed in tolerance to glyphosate: E. grandis was more sensitive to herbicide than E. urograndis and E. urophylla. No marked difference that would explain the observed differential tolerance was found in the anatomical structure of the different clones.
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