Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-06-19T16:28:13Z No. of bitstreams: 2 Dissertação - Vanessa Caetano de Castro Passos - 2017.pdf: 1573202 bytes, checksum: 01fa69aa015067f943979dc2884e2324 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-07-10T12:51:24Z (GMT) No. of bitstreams: 2 Dissertação - Vanessa Caetano de Castro Passos - 2017.pdf: 1573202 bytes, checksum: 01fa69aa015067f943979dc2884e2324 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-07-10T12:51:24Z (GMT). No. of bitstreams: 2 Dissertação - Vanessa Caetano de Castro Passos - 2017.pdf: 1573202 bytes, checksum: 01fa69aa015067f943979dc2884e2324 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-04-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Control of narrow leaf weeds is still a major challenge for cattle ranchers, mainly because there are still no herbicides available to control weeds such as grasses. A possible solution to this problem would be to renew the pasture and use some product that provides protection against the action of herbicides graminicidas at the time of sowing of the fodder, denominated of "safeners". The objective of this work was to evaluate the possibility of using the dietholate protector in the treatment of seeds in the species Brachiaria brizantha (Hochst.) Stapf., Brachiaria humidicola (Rendle.) Schweickerdt, Brachiaria ruziziensis (R. Germ & Evrard), Panicum maximum Jacq cv. Mombasa and Panicum maximum Jacq cv. Massai. Two experiments were carried out, the first one being carried out in the Seeds Laboratory of the Federal University of Goiás, Jataí Regional, evaluating the effect of the protector dietholate on the germination parameters of the evaluated species. And the second experiment was conducted in the municipality of Barra do Garças, at the experimental farm of the Federal University of Mato Grosso, where the use of dietholate as protector of the herbicide Clomazone was evaluated. The dietholate provided protective effect in doses up to 1200 mL of dietholate 100 kg-1 of seeds for the species Brachiaria brizantha cv. Marandú, Brachiaria humidicola and Brachiaria ruziziensis. However, doses above 800 mL of dietholate 100 kg seed-1 affected the seed germination parameters of the Panicum maximum cv. Mombasa and Panicum maximum cv Massai. Although seed protection was observed, the doses of dietholate used were insufficient to prevent the deleterious effects of the herbicide clomazone. / O controle de plantas daninhas de folhas estreitas ainda hoje é um grande desafio para os pecuaristas, principalmente porque ainda não existem herbicidas para controlar plantas daninhas do tipo gramíneas em pastagem. Uma possível solução para esse problema seria renovar a pastagem e utilizar algum produto que proporcione proteção contra a ação de herbicidas graminicidas no momento da semeadura das forrageiras, denominados de “safeners”. Com isso, objetivou-se com esse trabalho avaliar a possibilidade de uso do protetor dietholate no tratamento de sementes nas espécies Brachiaria brizantha (Hochst.) Stapf., Brachiaria humidicola (Rendle.) Schweickerdt, Brachiaria ruziziensis (R. Germ & Evrard), Panicum maximum Jacq cv. Mombaça e Panicum maximum Jacq cv. Massai. Foram conduzidos dois experimentos, sendo o primeiro realizado no Laboratório de Sementes da Universidade Federal de Goiás, Regional Jataí, avaliando o efeito do protetor dietholate nos parâmetros de germinação de sementes das espécies avaliadas. E o segundo experimento foi conduzido no município de Barra do Garças, na fazenda experimental da Universidade Federal do Mato Grosso, em que se avaliou o uso do dietholate como protetor do herbicida Clomazone. O dietholate proporcionou efeito protetor em doses até 1200 mL de dietholate 100 kg-1 de sementes para as espécies Brachiaria brizantha cv. Marandú, Brachiaria humidicola e Brachiaria ruziziensis. Porém, doses acima de 800 mL de dietholate 100 kg sementes-1 afetaram os parâmetros de germinação de sementes das espécies Panicum maximum cv. Mombaça e Panicum maximum cv Massai. Embora tenha sido observada proteção às sementes, as doses utilizadas de dietholate foram insuficientes para previnir os efeitos deletérios do herbicida clomazone.

Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T13:54:36Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DANDARA FIDÉLIS ESCOTO.pdf: 2090171 bytes, checksum: 1c4b35661ab0654fc646af3838138cf9 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T13:54:50Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DANDARA FIDÉLIS ESCOTO.pdf: 2090171 bytes, checksum: 1c4b35661ab0654fc646af3838138cf9 (MD5) / Made available in DSpace on 2017-06-05T13:54:50Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DANDARA FIDÉLIS ESCOTO.pdf: 2090171 bytes, checksum: 1c4b35661ab0654fc646af3838138cf9 (MD5) Previous issue date: 2017-03-20 / With the growth of world population and the advent of industrialization, the demand for abundant and profitable food production worldwide is increasing. There is then a need for strategies that minimize loss and changes in food products, especially those that are grown for long periods of time like grains and vegetables. In this bias arise the pesticides, marketed since the nineteenth century, increasingly specialized and chemically modified to achieve greater efficiency in pest elimination and a shorter period of time. When pesticides are used correctly, they minimize grain losses by over 40%, but when used improperly or above the recommended dosage, they can lead to environmental and public health impacts. In this context, Clomazone (2 - (2-chlorobenzyl) -4,4-dimethyl-1,2-oxazolidin-3-one), active principle of the commercial herbicide Gamit®, of the Isoxazolidinone family and belonging to toxicological class III is Of broad spectrum used for the control of annual grasses and broadleaf weeds in cotton, peas, squash, soybeans, sweet potatoes, tobacco, wheat and rice. However, this herbicide has a series of physico-chemical characteristics and distinct behavior depending on the environment where it is inserted which can cause the increase of its permanence in the environment and contamination of organisms that are not its origin targets. An alternative to reduce the environmental impact caused by herbicides is phytoremediation. Phytoremediation consists of a technique of removal and / or pollutants from environments using plants as environmental remediation agents. This study aimed to evaluate the ability of the Pistia Stratiotes plant species in phytoremediation of the herbicide clomazone in its commercial form of water resources. The assay lasted 24 days and counted on two herbicidal concentrations that were determined from the one hundred fold multiplication of the dose recommended for use in crops, setting up an acute exposure to the herbicide. The clomazone degradation kinetics analyzes were performed by analytical methods by high performance liquid chromatography coupled to a detector with CLAE-DAD diode array. After 24 days of experiment, it was possible to identify that the plant species was able to reduce the presence of the herbicide clomazone in water by 90% and also that despite the water exposure to P. stratiotes does not undergo morphological changes due to sensitivity to the compound. Thus, the results indicate that Pistia Straiotes is capable of phytoremediation of the herbicide clomazone of water resources. / Com o crescimento da população mundial e o advento da industrialização cada vez mais aumenta a demanda pela produção abundante e rentável de alimentos pelo mundo todo. Existe então a necessidade de estratégias que minimizem a perda e as alterações nos produtos alimentares, sobretudo os que são cultivados por longos períodos de tempo como grãos e hortaliças. Neste viés surgem os pesticidas, comercializados desde o século XIX, cada vez mais especializados e modificados quimicamente para atingir uma maior eficiência na eliminação de pragas e um menor período de tempo. Quando os pesticidas são usados corretamente, eles minimizam acima de 40% as perdas de grãos, mas quando usados de maneira incorreta ou acima da dosagem recomendada, podem conduzir a impactos no ambiente e na saúde pública. Neste contexto, o Clomazone (2 - (2-clorobenzil) -4,4-dimetil-1,2-oxazolidin-3-ona), princípio ativo do herbicida comercial Gamit®, da família das Isoxazolidinona e pertencente a classe toxicológica III é de amplo espectro usado para o controle de gramíneas anuais e plantas daninhas de folha larga em algodão, ervilhas, abóbora, soja, batata-doce, tabaco, trigo e arroz. Porém, este herbicida possui uma série de características físico-químicas e comportamento distinto dependentemente do ambiente onde for inserido o que pode causar o aumento de sua permanência no ambiente e contaminação de organismos que não são os seus alvos de origem. Uma alternativa para reduzir o impacto ambiental causado pelos herbicidas é a fitorremediação. A fitorremediação consiste em uma técnica de remoção e/ou de poluentes dos ambientes utilizando plantas como agentes de remediação ambiental. Este estudo teve como objetivo avaliar a capacidade a espécie vegetal Pistia stratiotes em fitorremediar o herbicida clomazone em sua forma comercial de recursos hídricos. O ensaio teve a duração de 24 dias e contou com duas concentrações o herbicida que foram determinadas a partir da multiplicação em cem vezes da dose recomendada para uso em lavouras, configurando uma exposição aguda ao herbicida. As análises da cinética de degradação do clomazone foram realizadas através de métodos analíticos por cromatográfica líquida de alta eficiência acoplada a detector com arranjo de diodos CLAE-DAD. Após os 24 dias de experimento foi possível identificar que a espécie vegetal foi capaz de reduzir em 90% a presença do herbicida clomazone na água e também que apesar da exposição agua a P. Stratiotes não sofre alterações morfológicas em decorrência de sensibilidade ao composto. Dessa maneira, os resultados indicam que a Pistia Straiotes é capaz de fitorremediar o herbicida clomazone de recursos hídricos.

Submitted by Sandro Camargo (sandro.camargo@unipampa.edu.br) on 2015-03-08T19:31:55Z No. of bitstreams: 1 117110034.pdf: 2400286 bytes, checksum: cb56e53d6549e75ae957bbc113c78f6d (MD5) / Made available in DSpace on 2015-03-08T19:31:55Z (GMT). No. of bitstreams: 1 117110034.pdf: 2400286 bytes, checksum: cb56e53d6549e75ae957bbc113c78f6d (MD5) Previous issue date: 2013-08-09 / As neuropatias tóxicas em animais de produção causadas por pesticidas correspondem a um importante grupo de enfermidades degenerativas do sistema nervoso central e periférico. No entanto, pouco se conhece sobre os reais impactos tóxicos de muitos desses produtos em animais e humanos e ao meio ambiente. O clomazone é um herbicida amplamente utilizado na região sul do Brasil por ser potente e supostamente seguro, com baixa toxicidade para animais e humanos. Até o presente não há relatos da intoxicação por esse herbicida em animais domésticos. O presente trabalho relata a intoxicação espontânea e experimental por clomazone em ovinos. De um rebanho com 103 ovinos, 20 animais apresentaram especialmente sinais clínicos neurológicos e respiratórios. A intoxicação foi reproduzida experimentalmente em três ovinos com a administração de 134 mg/kg de peso corporal de clomazone. Tanto nos casos naturais como experimentais o sinais clínicos incluíram taquipnéia, anorexia, apatia e dificuldade de locomoção com debilidade em membros torácicos e pélvicos, além de arrastar de pinças. Macroscopicamente não foram observadas alterações significativas. Microscopicamente, foram observadas especialmente vacuolização em substância branca e alguns vacúolos perineuronais e congestão de vasos das leptomeninges e do neurópilo. Ultraestruturalmente, as alterações vacuolares caracterizaram-se especialmente por tumefação em dendritos e processos astrocitários. A partir dos dados obtidos conclui-se que o clomazone é um agente tóxico capaz de causar neuropatia tóxica em ovinos. / The toxic neuropathies in farm animals caused by pesticides represent an important group of degenerative diseases of the central and peripheral nervous system. However, little is known about the real impact of many of these toxic products on animals and humans and to the environment. The clomazone is a herbicide that has been widely used in southern Brazil and includes one of the most potent herbicides and supposedly safe, with low toxicity to animals and humans. To date, there are no reports of this herbicide poisoning in domestic animals. This study describes the spontaneous and experimental poisoning due to clomazone herbicide in sheep. In a flock of 103 sheep, approximately 20 showed clinical signs especially neurological and respiratory. The poisoning was experimentally reproduced in three sheep with the administration of 134mg/kg body weight of clomazone. Both in natural and experimental cases the clinical signs included tachypnea, anorexia, apathy and limited mobility with weakness in forelimbs and hind limbs, drag tweezers, and gait changes. Macroscopically, there were no significant changes. Microscopically, were observed especially vacuolization in the white matter of brain, perineuronal vacuoles and, hyperemia congestion of the leptomeningeal and neuropil vessels. Ultrastructurally, the vacuolar lesions in the brain correspond to dendritic and astrocytic processes swelling. From the data obtained it was concluded that the clomazone is a toxic agent capable of causing toxic neuropathy in sheep.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Commercial formulations of the herbicide clomazone have been widely used in agriculture and fish farming to control weeds. Fish can be affected when the water reaches the drainage waterways, causing an imbalance in the aquatic ecosystem. In order to evaluate a possible contamination, we determined LC50 (96h) using a commercial formulation containing clomazone (Gamit®). We verified the metabolic, enzymatic, and genotoxic parameters as well as the oxidative stress in juvenile carp (Cyprinus carpio). Firstly, in order to determine the LC50 for the acute toxicity test, , the animals were exposed to the concentrations of 10, 20, 30, 40 and 50 mg/L of clomazone for 96 h and the fish behavior was analyzed during this period. After exposure, we verified the activity of the enzyme acetylcholinesterase (AChE) in muscle and brain of the dead fish and the live carp. Secondly, fish were exposed to the herbicide for 7 days, both in field (rice crop) and laboratory conditions. The concentration used in the rice crop and the laboratory was 0.5 mg/L. After the experimental period of 7 days under laboratory conditions and 7, 30, and 90 days under rice crop conditions, brain, liver and muscle of fish were sampled to carry out the toxicological analysis. The parameters studied were enzymatic activity of AChE, catalase (CAT) and glutathione S-tranferase (GST) in different tissues of this species. Some markers of oxidative stress, such as protein carbonylation and thiobarbituric acid reactive substances (TBARS) levels in liver tissue were also analyzed. Some metabolic parameters such as glucose, glycogen, lactate, protein, and ammonia as well as amino acids in liver and muscle of carp were also measured. In plasma, we measured glucose, lactate, and protein. Thirdly, carp were exposed to approximately 15% of the LC50 (5.0 mg/L) for 7 days. We verified the formation of reactive oxygen species (ROS) and micronucleus, and the comet test was performed in order to investigate the presence of DNA damage. In the first study we observed that fish exposed to 20, 30, 40 and 50 mg/L showed behavioral changes and LC50 (96h) was 30.35 mg/L. In addition, it was found that the activity of the enzyme AChE showed no significant changes in the brain of the fish that died at the concentrations tested (30, 40 and 50 mg/L), and the muscle of dead fish had an increase in this enzyme when they were exposed to 50 mg/L of clomazone. The activity decreased significantly in the brain AChE of fish that remained alive after 96 h of exposure to 10, 20 and 30 mg/L, but increased in the muscle of the surviving fish exposed to all concentrations tested. In the second experiment results showed that fish exposed to 7 days had no changes in AChE under field conditions. However, a decrease in the activity of this enzyme in muscle was observed under laboratory conditions. During the same period of exposition, the parameters of oxidative stress conditions changed both under the field and in laboratory conditions. However, metabolic parameters were altered only under field conditions. After 30 and 90 days, AChE activity did not change under field conditions. Disturbances in oxidative stress parameters and metabolism in different tissues were evident in the tissues up to 90 days after treatment. The results showed that the activity of AChE changed only under laboratory conditions, and that oxidative stress associated with metabolic parameters can be good indicators of contamination for clomazone in C. Carpio in rice field conditions. In the third experiment, the results showed an increased formation of ROS and a significant micronucleus (MN) and DNA damage in erythrocytes after exposure to 5.0 mg/L of the herbicide clomazone. Given these results, we can conclude that the herbicide studied can be dangerous to Cyprinus carpio when exposed to it due to increased ROS, which in turn cause oxidative stress evidenced by changes in enzyme markers, metabolic, genotoxic and oxidative stress. However, further studies are needed in order to verify the safety of this herbicide is when associating rice and fish. / As formulações comerciais do herbicida clomazone têm sido amplamente utilizadas na agricultura e na piscicultura para controle de plantas daninhas. Os peixes podem ser afetados quando as águas de drenagem atingem os cursos d água, acarretando um desequilíbrio no ecossistema aquático. Para avaliar uma possível contaminação foi determinada a CL50 (96h) utilizando-se uma formulação comercial contendo clomazone (Gamit®) verficando-se parâmetros metabólicos, enzimáticos, genotóxicos e de estresse oxidativo em juvenis de carpas (Cyprinus carpio). Para o teste de toxicidade aguda, a fim de determinar a CL50, os peixes foram expostos às concentrações 10, 20, 30, 40 e 50 mg/L de clomazone em água durante 96 horas e o comportamento dos peixes foi analisado nesse período. Após a exposição, foi verificada a atividade da enzima acetilcolinesterase (AChE) no cérebro e músculo dos peixes mortos e das carpas que sobreviveram. No segundo experimento, os peixes foram expostos ao herbicida durante sete dias, tanto em condição de campo (lavoura de arroz irrigado) como de laboratório. A concentração utilizada na lavoura de arroz e no laboratório foi de 0,5 mg/L. Decorridos os períodos experimentais de 7 dias em condições de laboratório, e 7, 30 e 90 dias em condições de lavoura de arroz, foram retirados o cérebro, o fígado e o músculo dos peixes para realização das análises toxicológicas. Os parâmetros enzimáticos analisados foram a atividade da AChE, catalase (CAT) e glutationa S-transferase (GST). Também foram analisados alguns marcadores de estresse oxidativo, como a carbonilação de proteínas e níveis das substâncias reativas ao ácido tiobarbitúrico (TBARS) no tecido hepático. Por fim, foram avaliados alguns parâmetros metabólicos como: glicose, glicogênio, lactato, proteína, amônia e os aminoácidos em fígado e em músculo de carpas. No plasma, foram feitas as dosagens de glicose, de lactato e de proteína. Em um terceiro experimento, as carpas foram expostas a aproximadamente 15% do valor obtido para a CL50 (5,0mg/L) por 7 dias. Posteriormente, foi verificada a formação das espécies reativas de oxigênio (EROs) e foram realizados os testes do micronúcleo e cometa (expresso por índice de dano do DNA). No primeiro experimento, foi observado que os peixes expostos a 20, 30, 40 e 50 mg/L, mostraram mudanças comportamentais e a CL50 (96h) foi 30,35 mg/L. Além disso, foi verificado que a atividade da enzima AChE não apresentou alterações significativas no cérebro dos peixes que morreram nas concentrações testadas (30, 40 e 50mg/L), e no músculo dos peixes mortos houve uma elevação na atividade desta enzima, quando eles foram expostos a 50 mg/L de clomazone. Já a atividade AChE diminuiu significativamente no cérebro dos peixes que sobreviveram após 96h de exposição a 10, 20 e 30mg/L, no entanto, aumentou no músculo dos peixes sobreviventes expostos a todas as concentrações testadas. No segundo experimento, os resultados mostraram que os peixes expostos a 7 dias não apresentaram alterações na AChE em condições de campo. No entanto, uma diminuição da atividade desta enzima no músculo foi observada em condições de laboratório. Durante o mesmo período de exposição, os parâmetros de estresse oxidativo mudaram tanto em condições de campo quanto em laboratório. Entretanto, os parâmetros metabólicos foram alterados apenas em condições de campo. Após 30 e 90 dias, a atividade da AChE não se alterou em condições de campo. Distúrbios nos parâmetros de estresse oxidativo e metabolismo foram evidentes nos tecidos até 90 dias após a aplicação. Os resultados mostraram que a atividade da AChE alterou apenas em condições de laboratório, e que marcadores de estresse oxidativo associados aos parâmetros metabólicos podem ser bons indicadores de contaminação para o clomazone em C. carpio em condições de campo. No terceiro experimento, os resultados mostraram um aumento da formação das EROs e significativo aumento dos MN e de danos no DNA dos eritrócitos após a exposição a 5,0 mg/L do herbicida clomazone. De acordo com os resultados obtidos, conclui-se que o herbicida estudado pode ser perigoso para as carpas quando expostas, devido ao aumento das EROs que por sua vez causam estresse oxidativo, evidenciado por alterações em marcadores enzimáticos, metabólicos, genotóxicos e de estresse oxidativo. Contudo, mais estudos serão necessários para verificar a segurança desse herbicida para os cultivos associados utilizando-se arroz e peixes.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Clomazone is a herbicide used for grass weed control in paddy rice. However, label rate may not provide efficient control for some weed species. For this reason many times it is necessity to increase the rate to improve weed control efficiency. Clomazone selectivity in rice is affected for soil type, the rate of the herbicide and the cultivar used, been necessary the use of safener to protect the plants when high rates are used. Though, it is necessary to adjust those factors for better use of this technology. For this reason, it were conducted two greenhouse experiments, the first with the objective of quantify the selectivity of clomazone in sand and clay soils, to quantify the protection of the dietholate on rice plants in these soil conditions. The second experiment had the objective of verify if phorate provides similar protective effect as dietholate provides for clomazone. The results allowed to conclude that the cultivars IRGA 409 and IRGA 417 are equally sensible to clomazone. In regards of soil type, clomazone cause higher injury to rice cultivated in sandy soil. The application of dietholate allows the increase of dose of clomazone. As much in the sandy soil as in the clay soil, dietholate as treatment of seeds allowed increase of the dose of clomazone in up to three times the dose in relation to the treatment without dietholate. Organophosphate phorate is capable to act as safener for rice when clomazone is applied, with similar safening ability as dietholate, conferring to the crop capability to support higher rates of clomazone. / O herbicida clomazone é utilizado para controle de poáceas na cultura do arroz irrigado. Porém, sua dose de registro para essa cultura não proporciona controle eficiente para determinadas espécies de plantas daninhas. Assim, há a necessidade de elevar sua dose para melhorar a eficácia sobre estas espécies. A seletividade do clomazone no arroz irrigado está condicionada ao tipo de solo, à dose do herbicida e a cultivar semeada, necessitando-se o uso de protetor de plantas quando se praticam altas doses de clomazone. Entretanto, há a necessidade de adequar esses fatores para melhor uso da tecnologia. Em vista do exposto, instalaram-se dois experimentos em casa de vegetação. O primeiro, com o objetivo de quantificar a seletividade de doses de clomazone em solo com característica arenosa e argilosa e verificar a ação do protetor de plantas dietholate sobre cultivares de arroz. O segundo experimento objetivou verificar se o organofosforado phorate proporciona efeito protetor semelhante àquele proporcionado pelo dietholate. Os resultados permitiram concluir que as cultivares IRGA 409 e IRGA 417 são igualmente sensíveis ao clomazone, e respondem igualmente aos tratamentos com dietholate. Tanto no solo arenoso como no solo argiloso, o dietholate como tratamento de sementes permitiu aumento da dose de clomazone em até três vezes a dose em relação ao tratamento sem dietholate. O phorate apresenta papel protetor na cultivar de arroz IRGA 417, contra a ação do herbicida clomazone, de forma equivalente ao protetor dietholate.

Made available in DSpace on 2016-01-26T18:56:17Z (GMT). No. of bitstreams: 1 Dissertacao Adriana.pdf: 365783 bytes, checksum: ed3827b47a2c0670fb4f16261594e0df (MD5) Previous issue date: 2007-10-30 / The objective of this work was the evaluation of soil translocation of two herbicides used in sugarcane (Saccharum spp.) under a infiltration flux of 10, 20, 40, 80 and 160 mm of water. The experiment was done in a greenhouse in columns with medium texture soil and ametryn application, at 3 kg.ha-1, before emergence or a mixture of clomazone, at 1 kg.ha-1, and hexazinone, at 0,25 kg.ha-1. The herbicides translocation, in the soil profile was evaluated by Sorghum bicolor as an indicative plant. Ametryn lixiviated limitedly; on the other hand, the clomazone + hexazinone mixture was highly transposable to layers deeper than 20cm in the soil profile. The effects of clomazone + hexazinone mixture and ametryn herbicides were reduced in the first 5 cm in soil (dilution effect) when submitted to 160 mm of water. The mixture clomazone + hexazinone was more effective than ametryn in the suppression of sorghum even when submitted the excessive infiltration flux of water. / Objetivou-se com este trabalho avaliar a lixiviação de ametryn (3 kg ha-1) e da mistura clomazone+hexazinone (1,0 + 0,25 kg ha-1) em colunas de solo, textura média, por meio da percolação de 10, 20, 40, 80 e 160 mm de água. O experimento foi realizado em casa de vegetação, e a translocação dos herbicidas no perfil do solo foi avaliada por meio de planta indicadora, utilizando-se Sorghum bicolor. O ametriyn apresentou baixa lixiviação, por outro lado, a mistura clomazone+hexazinone foi lixiviada para camadas abaixo de 20 cm de profundidade. Os efeitos dos herbicidas foram reduzidos nos primeiros 5 cm do perfil do solo quando submetidos a 160 mm de água.

Made available in DSpace on 2016-07-18T17:51:02Z (GMT). No. of bitstreams: 1 Dissertacao Adriana.pdf: 365783 bytes, checksum: ed3827b47a2c0670fb4f16261594e0df (MD5) Previous issue date: 2007-10-30 / The objective of this work was the evaluation of soil translocation of two herbicides used in sugarcane (Saccharum spp.) under a infiltration flux of 10, 20, 40, 80 and 160 mm of water. The experiment was done in a greenhouse in columns with medium texture soil and ametryn application, at 3 kg.ha-1, before emergence or a mixture of clomazone, at 1 kg.ha-1, and hexazinone, at 0,25 kg.ha-1. The herbicides translocation, in the soil profile was evaluated by Sorghum bicolor as an indicative plant. Ametryn lixiviated limitedly; on the other hand, the clomazone + hexazinone mixture was highly transposable to layers deeper than 20cm in the soil profile. The effects of clomazone + hexazinone mixture and ametryn herbicides were reduced in the first 5 cm in soil (dilution effect) when submitted to 160 mm of water. The mixture clomazone + hexazinone was more effective than ametryn in the suppression of sorghum even when submitted the excessive infiltration flux of water. / Objetivou-se com este trabalho avaliar a lixiviação de ametryn (3 kg ha-1) e da mistura clomazone+hexazinone (1,0 + 0,25 kg ha-1) em colunas de solo, textura média, por meio da percolação de 10, 20, 40, 80 e 160 mm de água. O experimento foi realizado em casa de vegetação, e a translocação dos herbicidas no perfil do solo foi avaliada por meio de planta indicadora, utilizando-se Sorghum bicolor. O ametriyn apresentou baixa lixiviação, por outro lado, a mistura clomazone+hexazinone foi lixiviada para camadas abaixo de 20 cm de profundidade. Os efeitos dos herbicidas foram reduzidos nos primeiros 5 cm do perfil do solo quando submetidos a 160 mm de água.

Saflufenacil is a new herbicide for broadleaf weed control. Limited information is available for crop tolerance, weed control and herbicide behavior in the rice environment. Studies were designed to 1 and 2) evaluate rice tolerance and weed control to saflufenacil in combination with clomazone and imazethapyr; 3) evaluate the absorption and translocation of imazethapyr and saflufenacil in weed species 4) assess saflufenacil degradation and persistence in soils; and 5) investigate the use of reference compounds during the determination of pesticide adsorption (Kd). None or minimal rice injury was observed from preemergence (PRE) application of saflufenacil. Intense injury (68%) was noted with combinations of clomazone (505 g ha-1) applied PRE and saflufenacil (50 g ha-1) applied postemergence (POST). Similarly, rice injury up to 83% was observed in earlier evaluations when saflufenacil was applied POST with imazethapyr. However, subsequent evaluations indicated rice recovery from herbicide treatments. Combination of saflufenacil with imazethapyr resulted in hemp sesbania control ≥ 88% and red rice control of 100%. Rice yield was not adversely altered by the herbicide treatments used in the clomazone and imazethapyr weed control programs. Imazethapyr plus saflufenacil provided a greater uptake (30%) and translocation (35%) of 14C-imazethapyr than imazethapyr alone in the TX4 red rice. Absorption of 14C-saflufenacil ranged from approximately 40 to 60% in hemp sesbania plants. At 12 and 24 hours after treatment a greater percentage of the absorbed saflufenacil was quantified above the treated leaf at the two lower light intensities. Similar trends were observed for basipetal movement of saflufenacil. An accelerated solvent extraction method was developed to extract saflufenacil from soil. Half-life averaged among soils was 59 and 33 days for saturated and field capacity, respectively. Saflufenacil persistence in the environment was 2 to 3 times longer under flooded conditions for most of the studied soils. Adsorption values were affected by soil to solution ratios, particularly when the soil-pesticide interaction resulted in Kd values > than 2 mL g-1. The use of reference compounds during Kd estimation allowed for calculation of a conceptual adsorption window generating a more comprehensive set of data with alternatives for comparison of soils and methods.

Tesis para optar al Título Profesional de Ingeniera Agrónoma y Al Grado de Magister en Ciencias Agropecuarias, Mención Producción de Cultivos / En Chile, la producción de haba está basada en el uso de cultivares cuyo hábito de crecimiento es indeterminado, caracterizado por una producción secuencial de flores y vainas desde la base de la planta hasta la parte superior, lo que conlleva a la obtención de un producto desuniforme en calidad. Recientemente se han realizado estudios en Chile para evaluar nuevos cultivares de haba de crecimiento determinado (Retaca y Verde Bonita). En este estudio se planteó como objetivos evaluar la selectividad de los herbicidas de pre y post emergencia (Clomazone y Bentazon) aplicados en haba de crecimiento determinado establecidas en dos fechas de siembra (mayo y junio) y caracterizar su crecimiento y rendimiento. Los resultados muestran que la selectividad de Bentazon y Clomazone no es igual para ambos cultivares y se modifica al hacer variar la época de siembra. Bentazon fue menos selectivo en el cultivar Verde Bonita, afectando su rendimiento de vainas y granos en la fecha de siembra más temprana (17 mayo). Clomazone disminuyó el rendimiento del cultivar Retaca en la fecha de siembra más tardía (17 de junio). La aplicación de los herbicidas Bentazon y Clomazone no afectó el normal crecimiento y desarrollo de los cultivares de haba de crecimiento determinado Verde Bonita y Retaca

Weed management programs in "Superior" potato with PRE and POST rimsulfuron treatments were investigated during 1992, 1993, and 1994. Common ragweed control by PRE combinations of metolachlor with linuron or metribuzin was higher when treatments included PRE or POST rimsulfuron. Common lambsquarters control was 93 to 96% by treatments that included POST rimsulfuron. Applications of 35 g ai/ha rimsulfuron plus 280 g ai/ha metribuzin POST controlled weeds comparable to sequential applications. Potato recovered from occasional injury caused by rimsulfuron, rimsulfuron plus metribuzin, and organophosphate insecticides combined POST with rimsulfuron plus metribuzin. Several acetolactate synthase (ALS)-inhibiting herbicides were evaluated for yellow nutsedge control in the greenhouse. Herbicides were applied POST to yellow nutsedge at actual or anticipated commercial rates. Yellow nutsedge control was 92 and 71% from halosulfuron and chlorimuron, respectively. Control ranged from 48 to 69% from primisulfuron, pyrithiobac, and rimsulfuron. Control from nicosulfuron and imazethapyr was 45 and 68%, respectively, while thifensulfuron and CGA-152005 had almost no activity on yellow nutsedge. Chlorimuron, imazethapyr, and halosulfuron were the only herbicides which reduced yellow nutsedge regrowth. Rrimsulfuron was evaluated in tomato at 26 and 35 g ai/ha, sequentially at 26 g/ha, at 26 g/ha plus metribuzin at 280 g ai/ha, and metribuzin at 280 g/ha were evaluated POST for weed control in transplanted "Agriset" tomato. Common lambsquarters was controlled by rimsulfuron at 35 g/ha. Rimsulfuron plus metribuzin gave consistent control of common ragweed but jimsonweed and goosegrass control was generally low. Rimsulfuron treatments caused < 12% injury to tomato. Tomato yield was consistently high in the metribuzin, metribuzin plus rimsulfuron, and rimsulfuron sequential treatments. In greenhouse studies, giant foxtail and large crabgrass control by rimsulfuron was above 95 and 85% respectively, but goosegrass was not controlled. Height of four tomato cultivars was not reduced, but dry weight of "Floradade" and "Sunbeam" was reduced by rimsulfuron. In 1993, 1994 and 1995, PPI clomazone at 390 g ai/ha, POST rimsulfuron at 35 g ai/ha, and PPI trifluralin at 560 g ai/ha were evaluated for weed control in transplanted "Keystone RG3" bell pepper. Common lambsquarters and jimsonweed control was highest by clomazone treatments, while common ragweed control was low from all treatments. Keystone RG3 in the field and greenhouse and "Camelot," "Jupiter" and "Memphis" in the greenhouse were injured by POST rimsulfuron and had lower height and dry weight than untreated controls. In the greenhouse, black nightshade control was below 23% and jimsonweed control was below 49% by rimsulfuron POST. The absorption, translocation, and metabolism of rimsulfuron was investigated in three Solanaceous weed species. Rimsulfuron uptake did not differ between black nightshade and eastern black nightshade while less labeled herbicide was absorbed by hairy nightshade. Black and eastern black nightshade translocated up to 50% of the labeled herbicide out of the treated leaf with 40 to 50% of the herbicide being moved to the actively growing regions of the plant. In hairy nightshade, an average 40% of the labeled herbicide was moved out of the treated leaf and less than 30% of the translocated herbicide was moved basipetally. Most major metabolites were apparent at 24 and 48 hours however, there were no differences in metabolite composition. Rimsulfuron will be an effective herbicide for use in weed management programs in potato and tomato, however rimsulfuron causes too much injury in pepper to be used. / Ph. D.