Induced Mutagenesis in Mungbean (Vigna radiata (L.) Wilczek)

A wide range of viable morphological and physiological mutants were observed in M2 and M3 progenies of mungbean (Vigna radiata (L.) Wilczek) cultivars (Vaibhav and Kopargaon-1) raised from seeds treated with different concentrations of sodium azide, ethyl methane sulfonate and different doses of gamma radiation. The most striking type of mutants obtained in the M3 progeny included plant habit, leaf structure, flower type, pod type, seed type, early-maturing and high-yielding and Lhb mutants. Some of these mutants are new and are being reported for the first time in this crop. The true breeding mutant lines of M3 generation were compared with their parent cultivar (control) to assess whether the induced genetic variability was statistically significant. These mutants can be better fitted in new cropping patterns, with improved agronomic management and good yielding ability, or can be used in the genetic improvement of mungbean crop. Chemical mutagens were more efficient than physical ones in inducing viable and total number of mutations. Along with simple viable mutations, multiple mutagenic effects on two or more characters were also found in all the mutagenic treatments. Differences in the mutation frequency and spectrum depends on the interaction of three factors such as mutagen, plant genotype, and physiological state of the organism at the moment of treatment. The Kopargaon-1 cultivar was more resistant towards mutagenic treatment than Vaibhav cultivar. All mutants were analyzed for their protein, albumin and globulin contents by Lowry's method and for protein banding patterns employing SDS Polyacrylamide Gel Electrophoresis. Mungbean mutants with high as well as low protein contents ranging from 29.3% to 14.75% vis-a-vis 22.2% in the control were isolated. Results showed that early flowering mutant and Lhb mutant differed between each other as well as with other mutants and controls in their protein-banding pattern. Our results indicated that mutational breeding was effective and useful for induction of agronomically important mutants in mungbean. (author)