Genetic characteristics of Pyricularia grisea and their pathotypes in Myanmar

Abstract

Rice blast disease is one of the major destructive fungal diseases of rice in Myanmar. In 2011, forty-six isolates of Pyricularia grisea were collected from Myanmar. The population structure of the P. grisea was determined by Rep-PCR using Pot2-TIR and MGR586-TIR primers separately. The combined dendrogram was constructed based on the different fingerprint patterns. Three fingerprint groups (designated as Type-A, Type-B and Type-C) were identified. Type-A and B were dominantly existed in Aung Ban area (Southern Shan State) whereas Type-C was prevalence in Hmawbi area (Yangon Division). Pathotypes of the representative isolates from each fingerprint group were examined by inoculating on a set of twelve Japanese differential rice cultivars and nine races (031.0, 032.0, 036.0, 106.4, 122.4, 132.4, 136.4, 432.5 and 437.5) were identified. This is the first characterization of genetic and pathotypic variations of P. girsea in Myanmar and there was no clear association between the genetic fingerprint profiles and pathotypic races.