Studies on Effect of Gamma Radiation on Biological Parameters and Male Sterility in Parental and F1 Generation of Spodoptera frugiperda (J.E. Smith)
The male pupae (7 days old) of fall armyworm, Spodoptera frugiperda were exposed to eight different doses of gamma radiation (25, 50, 75, 100, 125, 150, 175 and 200 Gy) using Co-60 source. Among the doses tested, a radiation dose of 100 Gy had induced >80.00% of sterility with least negative effects on adult emergence (71.00%), deformation (9.00%), adult longevity (6 days) and survival under food stress (59.00%) in parental generation. In F1 generation, larval duration was 23.67 days at 100 Gy compared to 20.33 days at unirradiated control. More than 50% of pupae (51.33%) were recovered with pupal weight of 1.51 g/10 pupae at 100 Gy. Emergence of F1 adult at 100 Gy was 66.23% with least percentage of deformation (12.60%) and F1 adults lived up to 5.55 days with 52.00% of survival under food stress. Biological parameters of F1 generation were severely affected at radiation doses ranging from 125 to 200 Gy. Percentage of male sterility was increased with increase in radiation doses. A radiation dose, 100 Gy has induced male sterility of 81.89% and 86.23% in parental and F1 generation with no deleterious effects on adult emergence, longevity, survival and other quality parameters of Spodoptera frugiperda.