Quantitative assessments on induced high yielding mutant lines in urdbean [Vigna mungo (L.) hepper]

Vigna mungo (L.) hepper is an important grain legume with immense potential for establishing food security worldwide. However, the low genetic variability due to the self-pollination mode of reproduction restricts its improvement endeavours. Therefore, the present study aimed at increasing the genetic variability and mean values of quantitative traits was undertaken by treating two widely cultivated varieties T-9 and Pant U-30, with low, intermediate and high doses of gamma rays and ethyl methanesulfonate in single and combination sets. The study accomplished selection of six mutant lines with augmented yield and manifold increase in genetic parameters, namely, genotypic coefficient of variation (GCV), heritability (h2), and genetic advance (GA) for economically important traits in M3 generation. A substantial increase in mean values of fertile branches per plant, pods per plant, and total plant productivity was noticed among the mutant lines. Phenotypic correlation between various character pairs showed a positive and significant relationship among the number of fertile branches, pods, total plant productivity, and negative association between the seed protein content and total plant yield in the selected mutant lines. In the control population, nitrate reductase activity (NRA), chlorophyll, carotenoid, and protein levels were significantly higher in M3 mutant lines in both varieties. The number and intensity of electrophoretic bands for seed protein in the mutant lines differed from the controls, indicating the mutagen induced polymorphism in protein bands among the mutant lines. In conclusion, the M3 high yielding mutant lines increased genetic variability, yield, protein, and pigment concentrations, isolated in this study, could serve as a valuable germplasm resource for black gram improvement programs.