The non-alcoholic fatty liver disease (NAFLD) is the most common liver pathology in developed countries with an estimated prevalence of 20 to 30% in the American population. A typically benign and asymptomatic pathology, NAFLD is characterized by hepatic steatosis and abnormal levels of hepatic enzymes stemming from an increase in circulating free fatty acids originating from white adipose tissue lipolysis, an increased de novo lipogenesis, reduced fatty acid oxidation and decreased hepatic triglycerides secretion, all within an insulin resistance context. NAFLD has the potential to progress to the non-alcoholic steatohepatitis (NASH), a condition marked by inflammation, advanced oxidative stress and fibrosis. NASH is expected to be the leading cause of liver transplant by 2020 due to its complications (i.e.: cirrhosis, hepatocellular carcinoma and liver failure). Various xenobiotics such as pesticides have been shown to promote the apparition and development of NAFLD. Of interest to this study is the neonicotinoid imidacloprid, more contemporarily known for its suspected role in the colony collapse disorder of various anthophilae species. Imidacloprid has been shown to induce hepatic oxidative stress in rats, a significant factor in the development of NAFLD and its progression to NASH. Lifestyle modifications, namely physical exercise, is a current treatment which has been proven beneficial to prevent and treat NAFLD by reducing hepatic steatosis, oxidative stress and improving insulin sensitivity. The role of any neonicotinoid on the development of NAFLD has yet to be examine and few have looked at the role of exercise in the treatment of NAFLD brought about by pesticide contamination.

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Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2017-02-10T13:10:47Z No. of bitstreams: 1 texto completo.pdf: 1372759 bytes, checksum: 6ef0326e806460e833c77ef93d7c71e2 (MD5) / Made available in DSpace on 2017-02-10T13:10:47Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1372759 bytes, checksum: 6ef0326e806460e833c77ef93d7c71e2 (MD5) Previous issue date: 2002-04-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O presente estudo foi conduzido na Fazenda Vista Alegre, no município de Jaboticatubas, MG, com o objetivo de avaliar o desempenho de um sistema de irrigação por gotejamento instalado em uma área cultivada com café Catuaí Vermelho, a eficiência da insetigação por gotejamento no controle do bicho- mineiro (Perileucoptera coffeella) e a redução da dosagem recomendada de um produto na insetigação. Na avaliação do desempenho do sistema de irrigação, utilizou-se a metodologia proposta por KELLER e KARMELI (1974) modificada por DENÍCULI et al. (1980). Foram feitas três avaliações do sistema, sendo a primeira antes de qualquer alteração no sistema. Após essa primeira avaliação, a pressão de operação do sistema foi aumentada e, então, feita a segunda avaliação. Depois dessa avaliação, procedeu-se à limpeza da tubulação, com injeção de ácido fosfórico, e, após 15 dias, realizou-se um segundo procedimento de limpeza, com injeção de hipoclorito de sódio juntamente com o ácido fosfórico. Após a lavagem do sistema, foi feita a terceira avaliação. Para avaliação do desempenho da insetigação, foi aplicado o inseticida imidacloprid via água de irrigação e via pulverização convencional, com três doses em cada método de aplicação (100%, 75% e 50% da dose recomendada), mais a testemunha, que não recebeu inseticida. A infestação da praga foi avaliada pela contagem de folhas minadas e com larvas vivas. Foram retiradas 10 folhas de cada planta, do 3 o ou 4 o par do terço médio da planta, em 10 plantas por parcela. Avaliou-se a infestação da praga antes da aplicação do inseticida e 15, 30, 45, 60 e 85 dias após a aplicação. Os resultados permitiram concluir que o coeficiente de uniformidade de distribuição de água do sistema de irrigação melhorou significativamente após os procedimentos de limpeza, evidenciando-se a eficácia da limpeza do sistema no desentupimento dos emissores; a insetigação foi mais eficiente que a pulverização convencional no controle do bicho-mineiro do cafeeiro; e a insetigação foi eficiente no controle da praga quando se utilizou 50% da dose recomendada, enquanto a pulverização convencional, com a mesma dose, não proporcionou controle sobre a infestação desse inseto. / This study was carried in Fazenda Vista Alegre, in district of Jaboticatubas, MG, to evaluates: the performance of a drip irrigation system installed in a Red Catuai coffee cropping area; the efficiency of insectigation by drip irrigation to control miner worm (Perileucoptera coffeella) and the reduction of the recommended dose of a product in the insectigation. To evaluates the drip irrigation system performance, it was used the methodology proposal by KELLER & KARMELI (1974) modified by DENÍCULI et al. (1980). Three valuations of the system were making. The first valuation was makes before any modification in the system. After first evaluate, the head emitters were increased and, after that, a second valuation was makes. After second valuation, a network cleaning procedure was making through injection of phosphoric acid in the network. After 15 days, a second network cleaning procedure was making through injection of both phosphoric acid and sodium hipochlorite. After wash of the system, a third valuation was makes. To evaluate the insectigation performance, the insecticide imidacloprid was applied through both irrigation water and conventional application system, with three doses for each application method (100%, 75% and 50% from recommended dose), beyond the witness, that which do not received insecticide. The insect pest infesting was evaluates by counting of mined leaves and with live worms in 100 samples, that witch were collected in each plot by taking 10 leaves from plant in 10 plants from plot. The leaves were taking from 3o. or 4o. pairs from medium or higher plant third part. The insect pest infesting was evaluates immediately prior to the application and 15, 30, 45, 60 and 85 days after insecticide application. The results obtained allowed conclude that irrigation system water distribution uniformity coefficient was meaningfully improved after cleaning procedures, evidencing the efficiency of the system cleaning to unblock the emitters; the insectigation was more efficient than conventional application system to control miner worm of the coffee plant; the insectigation was efficient to control the insect pest, when used 50% of the recommended dose, nevertheless the conventional application system, with equal dose, do not control the insect pest infest. / Dissertação importada do Alexandria

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-07-18T15:46:06Z No. of bitstreams: 1 BRUNO ADELINO DE MELO - DISSERTAÇÃO (PPGEA) 2013.pdf: 1637931 bytes, checksum: b7496e52c4463455ea29c78d3a3b2686 (MD5) / Made available in DSpace on 2018-07-18T15:46:06Z (GMT). No. of bitstreams: 1 BRUNO ADELINO DE MELO - DISSERTAÇÃO (PPGEA) 2013.pdf: 1637931 bytes, checksum: b7496e52c4463455ea29c78d3a3b2686 (MD5) Previous issue date: 2013-02 / Capes / Em condições de armazenamento, as sementes podem ser atacadas por insetospraga. Para sua proteção, o nim (Azadirachta indica A. Juss) tem se mostrado como uma alternativa ao uso de produtos sintéticos. Aliado a isto, o revestimento de sementes tem sido uma técnica que garante a fixação de defensivos agrícolas (inseticidas e fungicidas) e outros materiais à superfície das sementes, auxiliando estas na germinação. Diante o exposto, objetivou-se com este trabalho, avaliar o potencial de defensivos sintético e natural, associados à polímero para o controle de Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae) em sementes de amendoim. Os bioensaios foram conduzidos no Laboratório de Entomologia da Embrapa Algodão, Campina Grande, Paraíba. Sementes de amendoim (cultivar BR1) foram tratadas com inseticida (imidacloprido), fungicida (carboxin + thiram) e extrato aquoso das folhas de nim, associando-se ou não ao polímero, compondo os seguintes tratamentos: extrato aquoso de nim; inseticida; fungicida; polímero; polímero + inseticida; polímero + fungicida; polímero + extrato aquoso de nim (25%); e extrato aquoso de nim (50%), tendo como testemunha, sementes sem nenhum tratamento. Realizaram-se três bioensaios. O primeiro sobre eficiência dos produtos sobre adultos, avaliou o Número de Insetos Mortos (NºIM), Número de Ovos (NºO) e Número de Sementes Perfuradas (NºSP) durante 15, 30, 45, 60, 75 e 90 dias de armazenamento. A eficiência dos produtos sobre os adultos foi calculada pelo método de Abbott (1925). Os dados foram submetidos à Análise de Variância pelo teste F (P ≤ 0,05) e as médias quando necessário foram comparadas pelo teste de Scott-Knott (P ≤ 0,05). Adicionalmente foi realizada uma análise de correlação entre as principais variáveis. O segundo bioensaio, avaliou o potencial dos produtos em repelir adultos de A. diaperinus, utilizando-se para isto arenas circulares, tendo na base, seis recipientes distribuídos de forma equidistante entre si. Foram distribuídas de forma alternada, sementes sem tratamento e sementes que receberam um dos tratamentos mencionados anteriormente. No centro da arena liberou-se 15 casais de A. diaperinus e após 24 h, registrou-se o número de insetos em cada recipiente. As escolhas de A. diaperinus foram analisadas utilizando o teste do Qui-quadrado (P ≤ 0,05). Calculou-se ainda o Índice de Repelência (IR), submetendo-o à Análise de Variância pelo teste F (P ≤ 0,05) e as médias foram comparadas quando necessário pelo teste de Scott-Knott (P ≤ 0,05). O terceiro bioensaio avaliou a sobrevivência das larvas mantidas no pó das sementes tratadas com os produtos do primeiro bioensaio. Avaliou-se a sobrevivência das larvas até o décimo dia após a liberação das mesmas no substrato. Com o número de larvas vivas em cada tratamento, realizou-se uma Análise de Sobrevivência pelo teste Log-Rank utilizando o método D. Collet, comparando-se individualmente a sobrevivência de larvas submetidas aos produtos, com a sobrevivência das larvas na testemunha. Os tratamentos com inseticida e fungicida, associados ou não ao polímero foram eficientes para o controle dos insetos, com reduções no NºO e NºSP. Para repelência, a associação do inseticida, fungicida ao polímero apresentou os melhores resultados para o IR. As larvas submetidas ao pó das sementes tratadas com inseticida, fungicida e polímero + inseticida tiveram suas sobrevivências alteradas negativamente, com 100% de mortalidade em até 120 horas. Os tratamentos com extrato de nim, associado ou não ao polímero não exerceram efeito significativo sobre nenhuma das variáveis estudadas. / Under storage conditions, seeds can be attacked by pest insects. For their protection, the neem (Azadirachta indica A. Juss) has been shown as one alternative to synthetic products. In addition, seeds recovering has been a technique which guarantees insecticides and fungicides fixation and other materials on seeds surface, aiding the seeds germination. Thus, this work aimed evaluate the potential of synthetic and natural products associated to polymer to the control of Alphitobius diaperinus (Panzer, 1797) (Coleoptera: Tenebrionidae) on peanut seeds. Bioassays were carried out at the Laboratory of Entomology of Embrapa Cotton, Campina Grande, Paraíba. Peanut seeds (cultivar BR1) were treated with insecticide (imidaclroprid), fungicide (carboxin + thiram) and aqueous extract of neem leaves, associated or not to polymer, constituting the followed treatments: aqueous extract of neem, insecticides, fungicides, polymer, polymer + insecticide, polymer + fungicide, polymer + aqueous extract of neem (25%) and aqueous extract of neem (50%) and control (seeds without treatment). Three bioassays were accomplished. The first one about products efficiency on adult insects, evaluated the Number of Dead Insects, Eggs and punched seeds during 15, 30, 45, 60, 75 and 90 days of storage. The products efficiency on adult insects was calculated by Abbott method (1925). Data were submitted to Variance Analysis by F test (P ≤ 0,05) and means compared by Scott-Knott test (P ≤ 0.05), when necessary. Additionally, a correlation analysis between the principal variables, were realized. the second bioassay evaluated the products capacity in repelling A. diaperinus adults, by using circular arenas, with six recipients in its basis distributed in an equidistant way among them. Seeds without treatment and with one of the treatments mentioned before were distributed by alternative way. In the center of the arena 15 A. diaperinus couples were released and after 24 hours the number of insects in each recipient was recorded. A. diaperinus choices were analyzed using the ChiSquare test (P ≤ 0.05). The Repellence Index was also calculated, submitting it to Variance Analysis test (P ≤ 0.05) and means compared by Scott-Knott test (P ≤ 0.05) when necessary. The third bioassay evaluated larval survival kept in seed powder treated with the products of the first bioassay. Larvae survival until ten days after insect release in the substrate was evaluated. By the number of alive larvae in each treatment, a survival analysis using Logrank test (D. Collet Method) was accomplished, in which the survival of larvae submitted individually to products were compared to the survival of larvae in the control. The treatments with insecticide and fungicide, associated or no to polymer were efficient to control insects, reducing the number of eggs and punched seeds. For repellence, the association of insecticide e fungicide to polymer presented the best results for the Repellence Index. Larvae submitted o seeds powder treated with insecticide, fungicide and polymer + insecticide obtained their survival negatively altered, with 100% of mortality within 120 hours. Treatments with neem extract, associated or not to polymer, did not affected significantly on none of the variable.

Memoria para optar al Título Profesional de Ingeniero Agrónomo Mención: Sanidad Vegetal / The effect of two formulations of imidacloprid, Confidor Forte 200 SL and Winner®, to control Pseudococcus longispinus (Targioni y Tozzetti) and their impact on Neoseiulus californicus (McGregor) in avocado trees was studied during the 2004 season. Treatments were applied in two avocado commercials orchards, one in Isla de Maipo (Metropolitan Region) on 5 year-old trees, and the other in Lliu-lliu (5th Region) on 11 year-old trees. The products were applied to the foliage with a hand spray gun, or localized to the bark of the trunk with a pistol sprayer, or painting a circle around it with a paintbrush.

Amphibians have been facing global declines over the last decades due to direct and indirect effects of anthropogenic activities. One of the leading causes is environmental contamination, particularly that of waterbodies which are used by many amphibian species for reproduction, development, and adult life. An important source of contamination comes from agricultural runoffs of pesticides such as neonicotinoids, which are known to alter anuran survival, behaviour, predation stress response, and development. However, few studies have investigated the possible interactions between neonicotinoids and natural environmental stressors which could alter the strength and direction of observed neonicotinoid effects. This study investigated how a concentration of imidacloprid (a neonicotinoid) measured in surface waters interacted with high population density, an important environmental stressor, to influence behaviour and development across metamorphosis in wood frogs (Lithobates sylvaticus) known to breed in agricultural landscapes. I reared tadpoles in a fully crossed design experiment, between two densities (0.33 and 1 tadpole/L) and clean vs contaminated water (10 µg/L imidacloprid). Behaviours were measured in the absence and presence of predation cues using open-field tests at three distinct developmental stages, up to the metamorph stage. I found that imidacloprid did not interact with population density or independently affect behaviours in the absence of predation cues. However, individuals raised at high density compared with low density were more active at an early developmental stage but less active at metamorphic climax. Furthermore, both density and imidacloprid independently decreased the natural behavioural response (i.e., “freezing”) of tadpoles to predation cues. Both treatments also slightly accelerated metamorphosis while only density altered final mass at metamorphosis. Finally, I found that distance travelled was weakly repeatable between aquatic stages but not repeatable across metamorphosis, a pattern that was not affected by treatments. This study provides novel insights on the ecotoxicology of imidacloprid in the presence of a natural stressor, highlighting the importance of including behavioural assays and stressors in studies of amphibian ecotoxicology.

Anthropogenic landscape changes threaten our ecologically and economically critical honey bees by decreasing the availability of quality foraging resources. Importantly, waggle dance analysis provides a versatile and relatively cost-effective tool for investigating the obstacles that honey bees face, such as habitat loss, in our changing landscapes. While this emerging tool has improved our understanding of honey bee foraging in specific landscape contexts, additional research is needed to identify broad trends that span across landscapes. For this dissertation, I used waggle dance decoding and analysis to investigate honey bee foraging, and sublethal stress responses, across three ecologically distinct landscapes in Virginia. In Chapter 1, I introduce waggle dances as a model study system for investigating honey bee foraging and sublethal stress responses by summarizing modern methodological advances in its analysis and emerging research gaps. In Chapter 2, I tested the effects of sublethal imidacloprid exposure on honey bee foraging and recruitment using a semi-field feeder experiment. In doing so, I report that honey bees decreased their foraging, but not recruitment, to an imidacloprid-laced sucrose solution, compared to a control solution. Together, these effects could potentially harm honey bee health by increasing their exposure to pesticides and decreasing their food intake. In Chapter 3, I compared the foraging distances communicated by waggle dancing nectar and pollen foragers across landscapes to explore the economic forces driving foraging to these resources. I observed higher overall and monthly nectar foraging distances compared to pollen foraging distances. Such results suggest that nectar foraging cost dynamics are driven by supply, while pollen foraging cost dynamics are driven by demand. In Chapter 4, I used waggle dance decoding to map and quantify foraging to agricultural grasslands in a mixed-use landscape. In doing so, I demonstrate that honey bees recruit to agricultural grasslands throughout the season, but that this land type was not more attractive than the broader landscape after correcting for foraging distance, which is a relevant cost that flying bees must consider. Additionally, I qualitatively observe a foraging hot spot, representing high honey bee interest, over a highly heterogenous section of the landscape. The collective results of this chapter identify agricultural grasslands as a potential management target and support the importance of landscape heterogeneity to honey bees/pollinators. In Chapter 5, I used waggle dance decoding to investigate honey bee foraging spatial patterns in the context of optimal foraging theory. In particular, I explore whether co-localized honey bee colonies forage optimally by converging on the same resource patches, or by partitioning the landscape in to distinct foraging territories. Spatial analysis revealed that the colonies widely distributed their foraging at the landscape-scale, with dances from the same and different colonies being similarly distributed, while also establishing distinct, patch-scale, colony-specific, foraging aggregations. Together, these results suggest that the honey bee foraging system produces an emergent foraging pattern that may decrease both within- and among-colony foraging competition. Finally, in Chapter 6, I place my research findings in the context of historical and current trends in honey bee behavioral ecology. Overall, my dissertation improves our understanding of honey bee foraging ecology across landscape contexts using waggle dance analysis, while demonstrating its versatility and effectiveness as a tool for ecologists. / Doctor of Philosophy / Honey bees collect nectar (carbohydrate source) and pollen (protein source) from flowers as their food for survival and reproduction. Human activities, such urbanization, change landscapes and threaten our critically important honey bees by decreasing the availability of flower-rich habitats. Importantly, honey bees share the location of good food sources with their nest mates using a communication behavior called the waggle dance. Interestingly, scientists can estimate the approximate location of the food sources communicated by waggle dancing bees through close observation and cutting-edge analysis. Therefore, we can "decode" honey bees' waggle dances to map their food collection, or foraging, patterns and investigate the obstacles that they face in our changing landscapes. For this dissertation, I used waggle dance decoding and analysis to investigate honey bee foraging across three different landscapes in Virginia. In Chapter 1, I introduce waggle dances as a tool for investigating honey bee behavior by summarizing the modern improvements in its analysis and areas where research is needed. In Chapter 2, I tested the effects of a sublethal exposure to a pesticide, imidacloprid, by observing the foraging and waggle dance behavior of bees visiting feeders with artificial food. I report that honey bees decreased their foraging, but not recruitment, while collecting an imidacloprid-laced sugar solution, compared to a solution without imidacloprid. In Chapter 3, I compared the foraging distances communicated by waggle dancing nectar and pollen foragers across landscapes to explore the economic forces driving foraging to these resources. I observed higher overall and monthly nectar foraging distances compared to pollen foraging distances. Such results suggest that nectar foraging is driven by supply, while pollen foraging is more driven by demand. In Chapter 4, I used waggle dance decoding to map and quantify foraging to agricultural grasslands (pastures and hay fields) in a landscape characterized by diverse land uses. In doing so, I demonstrate that honey bees recruit to agricultural grasslands throughout the season, but that this land type was not more attractive than the broader landscape after correcting for foraging distance. Additionally, I qualitatively observe a foraging hot spot, representing high honey bee interest, over a highly heterogenous section of the landscape. The collective results of this chapter identify agricultural grasslands as a potential management target and support the importance of landscape heterogeneity to honey bees/pollinators. In Chapter 5, I used waggle dance decoding to investigate the spatial patterns of honey bee foraging in the context of optimal foraging theory, which attempts to explain efficient resource collection strategies. In particular, I explore whether neighboring honey bee colonies forage optimally by converging on the same resource patches, or by dividing the landscape in to distinct foraging territories. We found that colonies distributed their foraging widely at the landscape-scale, with dances locations from the same and different colonies being similarly distributed, while also establishing distinct, patch-scale, colony-specific, foraging areas. Together, these results suggest that honey bees use a foraging strategy that decreases both within- and among-colony foraging competition. Finally, in Chapter 6, I place my research findings in the context of historical and current trends in honey bee behavioral ecology. Overall, my dissertation uses waggle dance analysis to improve our understanding of honey bee foraging behavior, while demonstrating its versatility and effectiveness as a tool for ecologists.

One of the objectives of this research was to evaluate the need for an additional imidacloprid seed treatment on ThryvOn® (Bayer Crop Science®, St. Louis, MO) cotton to effectively manage tobacco thrips, Frankliniella fusca (Hinds). While evaluating thrips densities and damage ratings, ThryvOn cotton continued to display reduced damage and thrips populations than non-ThryvOn. Thrips populations and damage ratings were consistently reduced when incorporating a higher rate of imidacloprid, but they were not reduced enough to justify the higher rates of imidacloprid. Another objective of this research was to evaluate the impact of aldicarb (AgLogic Chemical®, LLC; Chapel Hill, NC) and ThryvOn on reniform nematode, Rotylenchulus reniformis (Linford & Oliveira). The impact of aldicarb and ThryvOn technology had no impact on reniform nematode densities in Mississippi cotton throughout this study. The reduced thrips populations and damage ratings provided by ThryvOn cotton has the potential to improve integrated pest management in the southern U.S.

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The insecticide imidacloprid, has been found to be highly effective in suppressing hemlock woolly adelgid, Adelges tsugae. Laricobius nigrinus is a predatory beetle released as a biological control of adelgids in the eastern U.S. This project was designed to develop a pest management strategy that utilizes both tactics concurrently within the same site. It will assess the efficiency of this strategy in reducing HWA populations and improving the health of hemlock forests. The project was started in 2010 and data were collected annually through 2016. The project spanned three sites in three different states (KY, WV, and TN). Results show that tree health has generally declined across all sites for each year. HWA population index values are highly variable and are more strongly influenced by the occurrence of low winter temperatures than by treatment effect. Cross-correlation analysis of tree health and HWA population, revealed characteristics of their temporal relationship. In two of the three sites, tree health lagged up to three years behind changes in HWA population, and HWA populations lagged approximately one year behind changes in tree health. L. nigrinus did not establish at any site as of 2016. The lack of sustained recovery of the beetle may be attributable to the occurrence of extremely cold temperatures during the winters of 2014 and 2015 which produced subsequent crashes in the HWA population at two of the three sites. In TN, the L. nigrinus population may have never established due to a decline in the HWA population shortly after release. / Master of Science in Life Sciences