Mutation breeding in crop plants is an effective approach in improvement of crop having narrow genetic base such as soybean. The main objective of the present study is to determine the effect of different doses of gamma irradiation on different morpho-agronomic characteristics. Agronomic traits that were analyzed included; grain yield, number of pods/plant, number of seeds/plant and weight of 100 seeds and numbers of days to 50% flowering. Morphometric characterization of the descriptive data included plant height, stem diameter, number of leaves/plant, leaflet length, leaflet width, number of ramifications/plant, and pod length and width at 3 lodge stage. The results of the present study revealed that the two gamma irradiation doses used (0.2 kGy and 0.4 kGy) decreased significantly most of agronomic and morphological traits evaluated in M1 populations. Different effects of 0.2 kGy and 0.4 kGy irradiation were observed in M2 populations with significant increase of grain yields and yield components in all the three soybean varieties. In general, a significant decrease or no changes of morphological traits were observed for the two irradiation doses in M2 populations. The levels of changes varied among varieties. Potential high yielding mutants were identified in progenies of irradiated seeds

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