INHERITANCE OF BLAST-RESISTANCE IN SOME CHlNESE RICE VARIETIES AND THEIR DERIVATIVES

A genetic study was conducted on Chinese varieties and their derivatives which were classified into the To-to group on the basis of their blast resistance. Results obtained by the mutant method, in which fungus mutant on pathogenicity was used to identify resistance gene, showed a complete agreement with those by the hybridization method, which was of the common for gene analysis. This indicates that the mutant method can be effectively used for identification of blast-resistance gene. To-to type varieties tested were found to have two genes for resistance, Pi-k and Pi-a. Minehikari has an additional gene, Pi-m.