Study on the impact of mutagenic treatment on pollen and spikelet fertility and its relationship in rice (Oryza sativa L.)

The present study was conducted to study the impact of different mutagens on pollen and spikelet fertility. Pollen fertility and spikelet fertility per cent was found to be inversely proportional to increasing dose of the mutagen in all the treatments viz., gamma rays, EMS and its combination treatment. The range of per cent reduction in pollen fertility was observed from 16.67 per cent (100 Gy) to 26.62 per cent (300 Gy) in gamma rays treatment of the seeds. Reduction in pollen fertility due to EMS treatment and its combination treatment ranged from 13.57 per cent reduction (10 mM) to 24.16 per cent reduction (30 mM) and 20.62 per cent reduction (100 Gy + 30 mM) to 31.43 per cent reduction (300Gy + 30 mM) respectively. Spikelet fertility also showed similar relationship in all the treatments. The correlation coefficient between pollen and spikelet fertility was found to be positive and significant. The optimum dose of mutagen was also determined by using pollen and spikelet fertility per cent. The optimum dose was found to be 300 Gy, and 173 Gy + 30 mM for gamma rays and combination treatment respectively. Hence, this proves to be an easy method for determining optimum dose of mutagen.