Abstract
1. Water soaked seeds of a rice variety 'Hakkoda' were treated with radioactive ˆ<32>P in order :to obtain beneficial mutants. The breeding method employed in this study is shown in Table 1. 2. Consequently, a number of mutations were observed, but most of them were lower in yield than the control (the original variety). 3. However, a high yielding mutant line with-out inferior qualities was obtaind in the progeny of R2 variants selected as small morphorogical variant types, and was nominated as 'Fukei No. 53'. 4. 'Fukei No. 53', having small grain, dense ear, and strong culm, was higher in yield by about 6% than the original variety.
