Effect of combined mutagenic treatments on sensitivity and mutation frequency in rice

Abstract

Puce seeds were subjected to two sets of combination treatments of radiations and NMH. The effects of mutagenic treatments in the MI and M2 generations were recorded and discussed. Mutation frequencies estimated as number of mutations per 100 M, ears were not higher than the values expected on the basis of additive effects. When estimated as number of mutants per ]00 M plants, the frequencies revealed more than additive effects. The synergistic effect on mutant frequencies was due to increase in the segregation ratio of mutants. This effect was more pronounced at the higher dose combinations of fast neutrons and NMH.