Blast resistance evaluation and genetic inheritance of gene controlling leaf blast resistance in Dawk Pa-yawm Rai variety (GS23774)

Abstract

The landrace rice Dawk Pa-yawm Rai variety was highly resistant to 18 blast isolates, moderately resistant to 5 and susceptible to 2 blast isolates. Therefore, Dawk Pa-yawm Rai variety was broad-spectrum resistance to many blast isolates and can be used as genetic resource in breeding programs for blast disease resistance. The genetic inheritance of blast resistance in F2 population was identified. Seven hundred and thirty F2 plants from a cross between KDML105 (recipient) and Dawk Pa-yawm Rai (donor) were generated. The disease assessment revealed 524 F2 plants were resistant and 206 F2 plants were susceptible. The segregation of resistance and susceptible phenotypes showed a goodness of fit to the ratio 3:1 (R:S). The result found is important factor and useful in mapping of blast resistant gene in Dawk Pa-yawm Rai variety.