Data/hora: 10/06/2024 19:08:43

Provedor de dados: | 102
País: | Brazil
Título: | Genetic and phenotypic characterization of isolates of Pyricularia grisea from the rice cultivars epagri 108 and 109 in the State of Tocantins
Autores: | PRABHU,ANNE S.; FILIPPI,MARTA C.; ARAUJO,LEILA G.; FARIA,JOSIAS C.
Data: | 2002-11-01
Ano: | 2002
Palavras-chave: | Magnaporthe grisea; Molecular markers; Oryza sativa; Rep-PCR analysis; Rice blast.
Resumo: | An epidemic of rice (Oryza sativa) blast occurred on cultivars Epagri 108 and 109 in the municipalities of Lagoa da Confusão and Duerê in the State of Tocantins, during the rice-growing season 1998-99. DNA fingerprinting and virulence phenotype analysis were utilized to determine the diversity of Pyricularia grisea isolates collected from these cultivars in one epidemic year. Rep-PCR analysis of isolates was done by using two primer sequences from Pot2. Two distinct fingerprint groups or lineages were identified among 53 isolates collected from nine different commercial fields. The virulence pattern of isolates retrieved from these two cultivars was analyzed in artificial inoculation tests utilizing 32 genotypes in the greenhouse. A dendrogram constructed from virulence phenotype data showed a single group considering 77% similarity level. The predominant pathotype IB-45 was represented by 47 of the 53 isolates corresponding to 83%. Four other pathotypes (IB-1, IB-9, IB-13 and IB-41) were identified at random among the isolates from these cultivars. There was no relation between rep-PCR grouping and pathotypes. The results showed that the isolates of P. grisea recovered from cultivars Epagri108 and 109 in farmers' fields had narrow phenotypic and genetic diversity. The blast outbreak on these two cultivars one year after their introduction could be attributed to the new pathotype IB-45 or its increase, which was hitherto existing in low frequency.
Tipo: | Info:eu-repo/semantics/other
Idioma: | Inglês
Identificador: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-41582002000600002
Editor: | Sociedade Brasileira de Fitopatologia
Relação: | 10.1590/S0100-41582002000600002
Formato: | text/html
Fonte: | Fitopatologia Brasileira  v.27 n.6 2002
Fonte: | info:eu-repo/semantics/openAccess