Murcha-de-ceratocystis em Mangifera indica, Colocasia esculenta e Tilia americana

• Ano de defesa: 2014
• Autor(a) principal: Oliveira, Leonardo Sarno Soares
• Orientador(a): Alfenas, Acelino Couto
• Banca de defesa: Guimarães, Lúcio Mauro da Silva , Ferreira, Maria Alves , Brommonschenkel, Sérgio Hermínio
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Fitopatologia
• Departamento: Etiologia; Epidemiologia; Controle
• País: BR
• Palavras-chave em Português: Ceratocystis fimbriata; Tilia americana; Variabilidade genética
• Palavras-chave em Inglês: Ceratocystis fimbriata; Tilia americana; Genetic variability
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::FITOPATOLOGIA
• Link de acesso: http://locus.ufv.br/handle/123456789/1063

Ceratocystis fimbriata is currently recognized as a complex of many cryptic species that affect mainly woody plants in Brazil and worldwide. In recent years, some of the descriptions of new species within this complex were based solely on variation of ITS sequences, such as the description of three new species obtained from mango. However, the cloning of PCR fragments of ITS gene region from single ascospores isolates of C. fimbriata showed overlap of sequences, showing that it is not possible to correct the reading of the amplified fragment, making the description of new species doubtful.Thus, the present work aimed to study the taxonomy of the fungus obtained from mango, taro and basswood by using different genes instead ITS and also evaluated the relationships of populations of the fungus obtained from mango and taro using mircrosatellite markers. Phylogenetic analysis of mating type genes , TEF - 1α and β - tubulin indicated that isolates from mango and taro have low genetic variability and reside in a single group that includes isolates from sweet potato, from which the species was originally described. No significant morphological variation was observed in isolates from mango and taro and mating experiments showed that they are able to cross to each other and also cross with isolates from sweet potato, suggesting they all belong to a single biological species. The values of gene and genotypic diversity, and analysis of dendrograms based on allele frequency, it was possible to identify natural and introduced populations of the fungus. The isolates obtained from basswood were identified as a new species and described as Ceratocystis tiliae, based on phylogenetic analyzes, differences in mycelial growth, pigmentation of the mycelium and host specificity.