Studies on the Biology of Spotted Bollworm Earias vittella (Fab.) on Okra

The duration of incubation, larval and pupal period of Earias vittella varied from 2.6 to 3.8, 8.2 to 9.0 and 7.8 to 8.6 days during June, July and August, compared to 4.4 to 4.8, 9.8 to 12.2 and 9.8 to 10.2 days during September, October, November, respectively. Highest fecundity (206.4 eggs/female) was recorded during September and lowest (187.4 eggs/female) in June. The pre-ovipositional period varied from 1.8 to 0.44 days in August to 3.6 ± 0.54 days in November, whereas the oviposition and post-oviposition period ranged from 2.2 ± 0.44 (August) to 4.2 ± 0.44 in November and 8.4 ± 0.54 in June to 12.2 ± 0.83 in November. The sex ratio was mainly female biased during most of the period except in October and November when it was male biased.