Population Structure and Pathotype Diversity of the Wheat Blast Pathogen Magnaporthe oryzae 25 Years After Its Emergence in Brazil

Autor(es)

Nunes Maciel, Joao L. ^[1] ; Ceresini, Paulo C. ^[2] ; Castroagudin, Vanina L. ^[3] ; Zala, Marcelo ^[4] ; Kema, Gerrit H. J. ^[5] ; McDonald, Bruce A. ^[6]

Afiliação do(s) autor(es)

^[1] Embrapa Trigo. BR-99001970 Passo Fundo

^[2] Univ Estadual Paulista UNESP. Dept Fitossanidade Engn Rural & Solos

^[3] Univ Estadual Paulista UNESP. Dept Fitossanidade Engn Rural & Solos

^[4] Inst Integrat Biol IBZ. Swiss Fed Inst Technol ETH Zurich

^[5] Plant Res Int. Univ & Res Ctr

^[6] Inst Integrat Biol IBZ. Swiss Fed Inst Technol ETH Zurich

• Tipo de documento: Artigo Científico
• Fonte: PHYTOPATHOLOGY; v. 104, n. 1, p. 95-107, JAN 2014.
• Citações Web of Science: 56

Resumo

Since its first report in Brazil in 1985, wheat blast, caused by Magnaporthe oryzae (anamorph: Pyricularia oryzae), has become increasingly important in South America, where the disease is still spreading. We used 11 microsatellite loci to elucidate the population structure of the wheat blast pathogen in wheat fields in central-western, southeastern, and southern Brazil. No subdivision was found among the wheat-infecting populations, consistent with high levels of gene flow across a large spatial scale. Although the clonal fraction was relatively high and the two mating type idiomorphs (MAT1-1 and MAT1-2) were not at similar frequencies, the clone-corrected populations from Distrito Federal and Goias, Minas Triangle, and Sao Paulo were in gametic equilibrium. Based on these findings, we propose that populations of the wheat blast pathogen exhibit a mixed reproductive system in which sexual reproduction is followed by the local dispersal of clones. Seedling virulence assays with local wheat cultivars differentiated 14 pathotypes in the current population. Detached head virulence assays differentiated eight virulence groups on the same wheat cultivars. There was no correlation between seedling and head reactions. (AU)

• Processo FAPESP: 13/10795-0 - 10th International Congress on Plant Pathology/5th International Sympoium on Rhizoctonia
• Beneficiário: Paulo Cezar Ceresini
• Modalidade de apoio: Auxílio à Pesquisa - Reunião - Exterior
• Processo FAPESP: 13/10655-4 - Desvendando a origem local da brusone do trigo (Magnaporthe oryzae) no Centro Sul do Brasil e evidências da emergência de resistência a fungicidas estrobilurinas em populações do patógeno
• Beneficiário: Paulo Cezar Ceresini
• Modalidade de apoio: Auxílio à Pesquisa - Regular