Fatores determinantes do ataque de Tuta absoluta ao tomateiro

• Ano de defesa: 2006
• Autor(a) principal: Bacci, Leandro
• Orientador(a): Picanço, Marcelo Coutinho
• Banca de defesa: Guedes, Raul Narciso Carvalho , Sediyama, Maria Aparecida Nogueira
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fitotecnia
• Departamento: Plantas daninhas, Alelopatia, Herbicidas e Resíduos; Fisiologia de culturas; Manejo pós-colheita de
• País: BR
• Palavras-chave em Português: Tomate; Manejo integrado de pragas; Traça do tomateiro; Dinâmica populacional; Tabela de vida; Tuta absoluta
• Palavras-chave em Inglês: Tomato; Integrated pest manegement; Population dynamics; Tuta absoluta
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA
• Link de acesso: http://locus.ufv.br/handle/123456789/1158

The objectives of this research were: i) to determine the effect of phenology of the tomato plant, climatic elements, natural mortality, and use of insecticides on the seasonal variation of population levels of Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), and ii) to construct and analyze ecological for T. absoluta in different seasons in order to identify critical life stages and mortality key factors of this insect pest. The use of insecticides reduced the injury by T. absoluta, but not enough to keep the pest below the economic injury level during the season most favorable to population growth. T. absoluta often reached the status pest after fruit formation. The period of highest density of mines and fruits attacked by T. absoluta in farms without application of insecticides was between the 4th week of August and 2nd week of January. However in farms where insecticides were applied, the highest density mines and bored fruits was observed between 4th week of September and 2nd week of January. Natural mortality along with direct and indirect effects of climatic elements were responsible for the low population level of T. absoluta during the summer and autumn. Decrease in natural mortality of the insect and increase of wind speed and air temperature were proximal causes of seasonal cycles of population growth of the tomato leafminer. On the other hand, population reduction correlated with increase in natural mortality and direct and indirect effect of rainfall on T. absoluta. The natural mortality of the leafminer was high and variable among the period studied, and numerous factors caused population reduction in the spring e summer and population increase during the autumn and winter. The critical stage of mortality of T. absoluta was larva, especially late instars, which are more venerable to the mortality factors. Key mortality factors in the spring-summer and autumn-winter were the predaceous wasp Protonectrina sylveirae and the parasitoid Bracon sp., respectively.