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Mutagenesis is a well-known technique for introducing new variants into crop plants. In the present study, M2 populations were generated in the cowpea (Vigna unguiculata (L.) Walp.) variety CO7 using gamma irradiation. The M2 progeny were used to investigate the effectiveness of the gamma irradiation doses and examined for the agronomic traits. The genomic variation present in the mutants and their parents was analysed using five SCoT markers. Marker analysis revealed a total of 87 amplicons and among these, 20 amplicons showed polymorphism. The highest numbers of amplicons were observed at SCoT10 (39), while the lowest number of amplicons was produced by SCoT09 (07). The percentage of polymorphism ranged from 18.18% to 28.57%, with an average of 21.12%. Polymorphic information content (PIC) values ranged from 0.197 to 0.345. Analysis of Molecular Variation (AMOVA) showed 12% and 88% between the genotypes and within the genotypes respectively. The constructions of 4 clusters were identified through Unweighted Pair Group Method with Arithmetic Mean (UPGMA) dendrogram tree based on the genetic distance deduced from SCoT marker analysis. Analysis of the genetic relatedness between parent and mutants through Principal Coordinate Analysis (PCoA) revealed two main groups. The present study concludes that the genetic variability induced by gamma irradiation and inherited in the next generations. This research investigation supports that gamma irradiation alters the growth and yield traits, which is helpful for generating the cowpea improvement.

Induced mutagenesis by gamma rays plays a potent promising technology to be applied for crop improvement through breeding methods, especially in tiny florets possessing self- pollinated plants such as cereals. Finger millet (Eleusine coracana (L.) Gaertn.) which always ensured for valuable nutrients, as well as famine tolerant crop to supply food for global population throughout the year. The present study was performed to assess the spectrum and frequency of macro mutants induced by gamma radiations in M2 generation finger millet. The chlorophyll mutants viz., albina, xantha, chlorina and viridis and morphological mutants such as tall, dwarf, bushy, brittle stalk and broad leaf were recorded in different doses. Among the mutagen doses 600 Gy dose induced maximum increase in mean values and phenotypic and genotypic coefficients of variation for the plant height (cm), number of leaves per plant, leaf length (cm), number of tillers per plant, number of panicles per plant, panicle length, days to 50% flowering, and 1000 seeds weight. Except for panicle number/plant and 1000 seed weight, all traits showed high heritability in all doses. The results revealed a progressive decrease in mean values of quantitative traits with the increase in doses. The present study provides an idea about the optimum dose of gamma rays from a pool of doses that could be employed in future breeding programmes.