세 유형의 화학 돌연변이제 처리(1.5mol Na$N_2$ ＋0.75mol MNH, 0.75mo1 MNH＋0.75mo1 M-NH 및 0.5mol MNH＋0.5mol MNH)를 한 M$_2$ 유묘를 이용, Est 1, 2, 4, 5, GOT 1, 2, 3, LAP 1, 2 등의 isozyme band pattern에 대한 돌연변이율을 조사하였다. 1. 세 가지 돌연변이제로 처리된 M$_2$식물체에 대한 돌연변이율 조사를 실시하였는데 엽록체에 대한 돌연변이율은 폴랜드 품종인 Dema에서는 3.3%였고 사천006에서는 1.8%로 나타났다. 2. Esterase유전자좌에 대한 돌연변이율은 Dema에서 3.5%로 사천 006의 0%보다 높았으며 GOT와 LAP에서는 두 품종간 차이가 없었다. 3. 세 가지 isozyme중 대개의 돌연번이체가 Es-terase에 관계된 유전자좌에서 발생하였으며 (75% 차지) 나머지에서의 돌연변이율은 극히 미미하였다.
Mutation rate of M$_2$ plants that were treated with three types of double treatments of chemical mutagens(1.5mol Na$N_2$ ＋ 0.75mol MNH, 0.75mol MNH ＋ 0.75mol MNH and 0.5mol MNH ＋ 0.5mol MNH) were estimated on the rate of chlorophyll mutant, changes of isozyme loci ; esterase (Est), glutamate oxaloacetate transaminase(GOT ; AAT) and leucyl aminopeptydase(LAP ; AMP). Rate of chlorophyll mutants (3.3％ =no. of seedling carrying mutant / all number of M$_2$ seedlings $ imes$ 100) and rate of esterase isozyme loci mutants(3.5％ =no. of plant carrying mutant / all number of M$_2$ plant) in Dema were higher than one of Sacheon 6, but no significant differences in GOT, LAP. Among isozymes, most of mutants in M$_2$ plant of two varieties were found in esterase (73％ of total mutants were occurred in esterase loci). Although many of null bands were found in GOT 3, these were not repeatable and no real mutants. It might be due to qualities of starch, amount of extract buffer and degradation of isozyme during electrophoresis and staining.
