Resposta de Cotesia flavipes a voláteis de plantas de cana de açúcar atacadas ou não por Diatraea saccharalis

• Ano de defesa: 2013
• Autor(a) principal: Grisales, Luisa Fernanda Patiño
• Orientador(a): Lima, Eraldo Rodrigues de
• Banca de defesa: Gontijo, Lessando Moreira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Mestrado em Entomologia
• Departamento: Ciência entomológica; Tecnologia entomológica
• País: BR
• Palavras-chave em Português: Compostos voláteis orgânicos; Inimigo natural; Terceiro nível trófico; Forrageamento
• Palavras-chave em Inglês: Volatile organic compounds; Natural enemy; Third trophic level; Foraging
• Área do conhecimento CNPq: CNPQ::CIENCIAS BIOLOGICAS::BIOLOGIA GERAL
• Link de acesso: http://locus.ufv.br/handle/123456789/3973

Worldwide sugar cane plantations suffer the pest attack A major pest is the sugarcane borer Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae). A striking feature of D. saccharalis is the penetration on the stalk, feeding on the tissues; affecting the developmet point, resulting in a condition known as "dead heart" due to the presence of the fungus Colletotrichum falcatum The plants can protect itself from herbivores attack by a combination of constitutive and/or inducible defenses that reduces the performance of herbivores, interrupting the spread of the damage. Accordingly, plants respond to feeding herbivorous arthropods producing a series of secondary metabolites, including volatile organic compounds (VOCs), which are known to attract natural enemies. Natural enemies such as parasitoids, are able to exploit these volatiles to locate their prey, for exemple, using feeding chemical signals. Thus, behavioral studies are important for understanding the interactions that occur between organisms in a food Web. As the knowledge of the chemical compounds that mediate the location of plants infested with herbivores by natural enemies, to have a better understanding of insect-plant interaction influencing the third trophic level. Given this, in this study was investigated the responses of cotesia flavipes (Cameron) (Hymenoptera: Braconidae) to volatile plant sugar cane rustic and current (Archi, White pararia and RB867515) unscathed and infested by D. saccharalis. In the chapter 1 was investigated the preferences of C. flavipes to the set of plants induced to herbivory and plants unharmed in laboratory and semi-field conditions. The results show that the parasitic wasp provides different responses, in the laboratory showed choice for infested specie and semi-infested field conditions show no preference, but present parasitism in the host. In the second chapter we identify the volatile compounds emitted by plants infested with D. Saccharalis and undamaged plants of sugarcane. To access this result was used for GC-MS for the identiñcation of compounds, showing that when compared uninjured plants with infested plants were found and identified a larger quantity of volatile components in the infested plants, especially on the species Archi and White pararia, the profile of volatile of the specie RB867515 is very similar between infested and unharmed sugar cane plants. The results obtained through the identification of these volatile compounds may explain the outputs obtained in the chapter 1, which may mediate the foraging behavior of C. flavipes. In general it can be concluded that this wasp showed parasitism, independently of the complex plant-herbivore, reducing infestation and damage by D. saccharalis in sugarcane plants.