Resposta comportamental e seleção para resistência à fosfina em Rhyzopertha dominica F. (Coleoptera: Bostrichidae)

• Ano de defesa: 2010
• Autor(a) principal: Pimentel, Marco Aurélio Guerra
• Orientador(a): Faroni, Lêda Rita D'antonino
• Banca de defesa: Fadini, Marcos Antonio Matiello , Silva, Arienilmar Araújo Lopes da , Berbert, Pedro Amorim
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Entomologia
• Departamento: Ciência entomológica; Tecnologia entomológica
• País: BR
• Palavras-chave em Português: Resistẽ ncia a inseticidas; Fumigação; Taxa respiratória
• Palavras-chave em Inglês: Insecticide resistance; Fumigation; Respiration rate
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::ENTOMOLOGIA AGRICOLA
• Link de acesso: http://locus.ufv.br/handle/123456789/878

The phenomenon of phosphine resistance is widely distributed among Brazilian populations of insect pests of stored products. This scenario is due mainly to lack of gastightness on storage facilities that favors the development of resistance to phosphine, as well as the use of inadequate techniques of fumigation. The lack of gastightness of bulk warehouses and silos favors leaking, exposing the pest insects to sublethal concentrations of phosphine, which will help the development of resistance to phosphine by these populations. According the assumptions, the main focus of this study was to investigate the locomotory behavior of populations of Rhyzopertha dominica F. (Coleoptera: Bostrichidae) under sublethal concentrations of phosphine, and determine the magnitude of the development of phosphine resistance and its stability, determining possible physiological, behavioral and fitness costs associated. The exposure of insects to increasing concentrations of phosphine reduced their mobility, for the three studied populations of R. dominica. The lowest mobility of insects reduces exposure to the fumigant, compromising the effectiveness of fumigation. Thus, the locomotory activity of insect pests under sublethal concentrations of phosphine should be considered in studies of resistance management and integrated pest management of stored products. The evolution of resistance to phosphine was shown to be faster, with an increase of 69 times in 10 generations under selection. Resistance to phosphine showe≈ d stability in the resistant population, maintained without selection pressure for 10 generations. The insect respiration rate decreases with the evolution of phosphine resistance, while the population growth rate increases with the evolution of phosphine resistance. The loss of grain weight and body mass show no tendency to increase or decrease for the two populations, selected and not selected. The selected population showed a decrease in mobility over the 10 generations evaluated, while the unselected population showed an opposite behavior. However, flight capacity is increased during the generations of selection, while the population not selected did not affect takingoff for flight over the generations. The information generated in this study on the magnitude of the development of resistance to phosphine, the stability ofresistance, as well as the behavior of populations of pest insects under sublethal concentrations of phosphine provide subsidies for refining current techniques of fumigation and pest control used in integrated pest management of stored grains.