Abstract

                                Radiogenetical studies in rice received a fairly wide importance, as early as 1934, from the pioneering studies of Ramiah and his associates in India and those of Ichijima in Japan. The increased applica- tion of physical mutagens, attained prominance in the 'Atom Era' of forties and fifties, contributing to isolation of a large number of mutants in various crops, including rice. In the present studies, an attempt has been made to understand the relative mutagenic effects caused by ionizing radiations, namely, X-rays and gamma rays, on rice by (i) evaluating the relative sensitivity and (ii) the rate of chlorophyll mutation in M, generation.

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