Extrato de casca de café e óleo de tomilho no controle de Cercospora coffeicola Berk & Cooke em cafeeiro

• Ano de defesa: 2006
• Autor(a) principal: Pereira, Ricardo Borges
• Orientador(a): Alves, Eduardo
• Banca de defesa: Abreu, Mário Sobral de, Botrel, Élberis Pereira
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Lavras; Escola de Ciências Agrárias de Lavras (ESAL)
• Programa de Pós-Graduação: Programa de Pós-Graduação em Agronomia/Fitopatologia
• Departamento: Departamento de Fitopatologia
• País: BRASIL
• Palavras-chave em Português: Cafeeiro; Cercospora coffeicola; Indução de resistência; Extratos vegetais; Óleos essenciais; Coffee; Indiced resistance; Plant extracts; Thyme oil
• Área do conhecimento CNPq: Ciências Agrárias
• Link de acesso: https://repositorio.ufla.br/handle/1/2965

The objectives of this work were: (i) to assess the effect of different doses of coffee berry husk extract (CHE) and thyme essential oil (TEO) on the germination and mycelial growth of Cercospora coffeicola; (ii) to assess the efficiency of CHE and TEO as possible resistance inducers in green house conditions; (iii) to biochemically characterize the effects of the resistance inducers CHE and TEO through the assay of peroxidase activity and lignification; (iv) to observe through scanning electron microscopy (SEM), the effects of these inducers on the spore germination and fungal development. It was observed that CHE had no fungitoxic effect on C. coffeicola conidia, promoting higher conidia germination in comparison with the control. TEO presented fungitoxic effect to the conidia in the concentrations of 500, 1000 and 2000ppm. The mycelial growth was inhibited in all CHE and TEO doses applied. In the green house trials, CHE (150g.L-1) and TEO (500ppm) reduced C. coffeicola incidence to 28.1% and 20%, respectively, in comparison with the control treatment. Plants that received only CHE had peaks of peroxidases activity in the seventh and eleventh days after treatment and, when inoculated the plants had similar behavior. Plants treated with TEO showed activity peaks in the second and third days after treatment, having another peak in the ninth day which was observed until the fourteenth day. In the inoculated plants it was observed a peak only in the first day after inoculation. There were not significant differences in the lignin concentrations fourteen days after treatment spraying. It was observed through SEM that CHE promoted better conidial germination and fungal development; on the other hand TEO reduced conidial germination and fungal development in all the times evaluated.