Effects of Gamma Radiation on Mature Pupae of the Cotton Bollworm, Helicoverpa armigera (HÜBNER) and Their F1 Progeny

Abstract

Mature male pupae of cotton bollworm, Helicoverpa armigera, from laboratory culture were irradiated at 0, 50, 100, 150 and 200 Gy with dose rate of 33.6 Gy/min in ⁶⁰Co gamma irradiator. The results were found to have 99.17, 97.50, 98.75, 97.92 and 99.06% moth emergence, 1.56, 3.54, 2.91, 5.39 and 8.33% moth deformation, 13.35, 10.20, 9.45, 11.65 and 11.10 days longevity of P₁ moths, 27.04, 30.49, 33.12, 48.84 and 62.73% sterility of P₁ moths respectively. Effects of radiation on F₁ progeny showed that survival of the immature stages of F₁ progeny significantly decreased with increasing doses irradiated to P₁ male and the sex ratio of the F₁ progeny was significantly skewed in favor of males. Longevity of F₁ male moths from male parents irradiated as mature pupae at 0, 50, 100, 150 and 200 Gy were 29.00, 26.13, 24.90, 26.35 and 22.55 days while those of F₁ female
moths were 17.60, 18.00, 17.55, 17.15 and 17.19 days respectively. Fecundity of F₁ female moths was not significantly different but the sterility of F₁ progeny was significantly different compared with untreated moths. The sterility of F₁ male moths were 26.17, 52.77, 92.1, 96.84, 100.00% while those of F₁ female moths were 26.17, 52.75, 84.76, 98.91 and 100.00% respectively.