Effect of chemical and physical mutagen in m1 generation and chlorophyll mutations in soybean (glycine max l. Merrill.)

Soybean variety ‘MACS 450’ was subjected to combination treatments of gamma rays (50 Gy and 100 Gy) and EMS (0.2% and 0.4%), different presoaked hours (12hrs, 16hrs and 20hrs) with 0.8% EMS, and gamma rays (50 Gy) with sodium azide (0.003 % and 0.005%) with an objective to induce variability for quantitative traits and estimate frequency and spectrum of chlorophyll mutations. In M 1 generation effect of mutagenic treatments was assessed on the basis of parameters survival (%), plant height reduction and seed sterility against control. Overall compare to all combination treatments 100Gy +0.4% EMS exerted more injurious effects in M 1 in the form of reduction in height (36.4%) and pod /plant (35.3). Among combination treatments of gamma rays + EMS and EMS treatment to presoaked seeds, the highest frequency of chlorophyll mutations (2.91% and 4.50%) was observed in 100 Gy + 0.4 % EMS and 16hrs PSW + 0.8% EMS respectively on M 2 plant basis. The results indicated that both these treatments are most effective to induce a wide range of genetic variability in soybean.