No abstract

The experiment was carried out during rabi 2018-19 and rabi 19-20 in the experimental field of College of Agriculture, Central Agricultural University, Imphal. Seeds of two genotypes of Indian mustard viz., CAULC-2 (local cultivar) and NRCHB-101 were exposed to three doses (1000, 1100 and 1200 Gy) of gamma rays, three concentrations of ethyl methanesulphonate (0.3, 0.5 and 0.7%) alone and in various combinations (1000Gy + 0.5%, 1100Gy + 0.5% and 1200Gy + 0.5%). Five different types of chlorophyll mutants viz., albina, chlorina, xantha, viridis and alboviridis were isolated from different treatments in M2 generation. Combination treatment of 1100 Gy+ 0.5% EMS produced the highest frequency of chlorophyll mutation in both the genotypes. Alboviridis and viridis types of mutants were more frequent in CAULC-2 and NRCHB-101 respectively, whereas albina type was least frequent in both the genotypes. CAULC-2 was more sensitive to mutagenic treatment as compared to NRCHB-101.