The dose of 25 Kr detected significantly the highest reduction of fertility percentage (80.5%) and number of filled grains/panicle (57.8) compared with the other treatments (Table 4). However, the differences among 15, 20 Kr and the control were not significant for fertility percentage. So, gamma-ray doses had some stimulatory effects on seed fertility which decreased with increase in gamma irradiation dose (Chemma et al., 2003). The measurements of variability in the treated plants were higher than those of the control. The range of variability was maximized at the highest dose of gamma-rays and ranged from 57.8 to 138 for number of filled grains/panicle. So, the doses of gamma-rays in the present work were able to induce marked additional variation within their population.