The dry, uniform and bold seeds of non-Basmati aromatic rice Badshah Bhog irradiated by gamma rays at Bidhan Chandra Krishi Viswa vidyalaya (BCKV), West Bengal. The different dose of gamma rays was 250Gy, 300Gy, 350Gy and 400Gy and without gamma-ray irradiated seeds used as control. The treated seeds were sown with spacing of 15 × 20 cm to raise M1 plants. The M2 plants were grown from M1, which were harvested individually spikelet fertility basis. After 10 days of seedling emergence chlorophyll mutation was screened in M2 population. The five different types of chlorophyll mutants observed in all doses, viz., albina, xantha, chlorina, striata and viridis. The albino chlorophyll mutant frequency was highest in all treatments. Mutagenic effectiveness and efficiency was observed maximum in nonbasmati aromatic rice at 300Gy and minimum at 350Gy. The effectiveness and efficiency of the mutagens used detect the frequency of desirable mutations. 

Key Words: Chlorophyll mutation, Genetic variability, Induced mutation, Mutagens