VARIETAL DIFFERENCES IN GAMMA-RAY INDUCED CHROMOSOME ABERRATIONS IN SOYBEAN

Abstract

When the seeds of 27 soybean varieties were exposed to gamma-rays, distinct varietal differences in the frequency of chromosome aberrations were found at the first root tip mitosis. The varieties tested could be divided into resistant and sensitive groups. F₂ seeds from crosses between resistant and sensitive varieties were irradiated and from the frequency distribution of chromosome aberrations it was concluded that the intervarietal differences were controlled mainly by a single recessive gene rs₁ which had been detected by Takaki and Yamashita to control the degree of seedling growth inhibition in both seed and growing plant irradiations.