Genetic and Pathogenic Diversity of the Rice Blast Pathogen

摘要: Rice blast caused by Pyricularia grisea (Rossman et al., 1990) (perfect state Magnaporthe grisea, Barr, 1977) continues to be a serious constraint rice production in both tropical and temperate regions (Ou, 1980, 1985). Occurrence of was recorded for the first time Thanjavur delta Tamil Nadu 1918 (McRae, 1920). The disease has occurred from country causing severe damage (Sundararaman, 1927; Thomas, 1930). Blast is common all three main ecosystems which grown namely, irrigated, rainfed uplands lowlands although incidence severity greater upland situations. existence strains pathogen differing pathogenicity noticed Sasaki (1922). However, intensive studies on pathogenic races this fungus initiated Japan only after some resistant cultivars such as Futaba, developed hybridisation, became susceptible cultivation nearly decade. Goto (1960, 1965) identified 13 placed them into groups. Following this, P. were intensified several countries resulting identification many races. differentials used different workers not identical.