Studies on the Life Cycle of Cryptoblabes Gnidiella Miller (Lepidoptera: Pyralidae) on Hybrid Sorghum

The life history of Cryptoblabes gnidiella Miller was investigated on hybrid sorghum, the caterpillars fed on the grains and webbed them in a silken thread, where they continued their feeding till pupation. Mean oviposition period was 59.12hrs. Female laid 31.00 eggs on an average. Freshly laid eggs were creamy white, somewhat conical, oval and had a size of 0.45 mm × 0.32 mm. The colour changed to light pale yellow and became translucent later and incubation period was 79.45 hrs. The average hatching was 65.03% and larvae passed through five instars, and full-grown larvae measured 11.91×1.99 mm cylindrical and brown. Total larval period was 8.80 days in July, which increased to 15.40 days during November with a mean period 11.92 days. The pupa measured 7.03×1.94 mm and pupal period was 4.40 to 11.00 days. The mean duration of life span was 23.40 days. The moths were small sized and grey, forewings smaller than hind-wings with dark grey and hind-wings were transparent having fringe like hairs on the posterior margin. The mean wing expanse of female varied from 14.26 to 15.36 mm and that of male 13.73 to 14.65 mm. The length from head to tip of abdomen in female and male was 7.72 mm and 7.38 mm, respectively. The sex ratio of male to female was 1:0.89.