Biology of Gaeumannomyces graminis var. graminis isolates from rice and grasses and epidemiological aspects of crown sheath rot of rice
AUTOR(ES)
Peixoto, Cecília N., Ottoni, Giselle, Filippi, Marta C. C., Silva-Lobo, Valácia L., Prabhu, Anne S.
FONTE
Trop. plant pathol.
DATA DE PUBLICAÇÃO
2013-12
RESUMO
A collection of Gaeumannomyces graminis var. graminis isolates obtained from symptomatic rice and grass plants in central and northern Brazil were studied in regard to pathogenicity on rice and cultural characteristics. For all isolates, only one type of lobed hyphopodia was observed both in the field and artificially inoculated plants. Perithecia were formed on artificial media and inoculated leaf sheaths. Hyphopodia were formed from ascosporic germ tubes. The hyphae under moist stress conditions produced dark brown chlamydospores that were initially hyaline. Large variation in the number of chlamydospores produced and duration of perithecia formation was observed among the isolates. Pathogenicity assays showed that 60-day old rice plants were more susceptible than 35-day old plants. The isolates from rice and grasses varied significantly in regard to disease severity on both rice seedlings and adult rice plants. In general, the isolates from rice were more aggressive than the isolates from grasses. Spontaneous infection of rice plants by ascosporic inoculum from perithecia on rice stubbles was observed in the greenhouse, suggesting their role as a source of primary inoculum in the field, which deserves further investigation.
Documentos Relacionados
- Detoxification of Benzoxazolinone Allelochemicals from Wheat by Gaeumannomyces graminis var. tritici, G. graminis var. graminis, G. graminis var. avenae, and Fusarium culmorum
- Purification and Characterization of a Secreted Laccase of Gaeumannomyces graminis var. tritici
- Mal-do-pé do arroz: hospedeiros e resistência varietal a Gaeumannomyces graminis var. graminis
- Cloning, Characterization, and Transcription of Three Laccase Genes from Gaeumannomyces graminis var. tritici, the Take-All Fungus
- Role of a phenazine antibiotic from Pseudomonas fluorescens in biological control of Gaeumannomyces graminis var. tritici.