Induced genetic variability and scope of selection for yield attributes in greengram (Vigna radiata L. Wilczek)
An experiment was conducted to generate a broad genetic variability through induced mutation using physical and chemical mutagens. Three doses each of gamma rays (20, 40 and 60kR), ethyl methane sulphonate (0.2, 0.4 and 0.6%), nitrosoguanidine (0.005, 0.010, and 0.015%), maleic hydrazide (0.01, 0.02 and 0.03%) and their combinations were administered to the seed of two greengram varieties, Sujata and OBGG-52. In M2 generation most treatment populations exhibited a reduction in population mean and increased in population variance for pods/plant, seeds/pod, 100 seed weight, yield/plant and the magnitude of such changes varied with mutagens, their doses and genotypes. A greater shift in mean and variance was observed in treatments with higher doses. The negative shift of mean was more pronounced in MH and its combined treatments in both varieties.