Effect Of Different Temperatures On The Development Of Spotted Bollworm, Earias Vittella (Fab.) (Lepidoptera: Noctuidae) In The Laboratory

Abstract

Earias vittella is a major lepidopteron pest of cotton in Pakistan and it causes heavy infestation in cotton crop. Present study of biology of Earias vittella carried out in the laboratory under controlled conditions at different temperatures (27, 31 and 35±1°C). E. vittella was reared on its natural diet cotton shoots, flowers and bolls. Highest mortality recorded in the first larval instars and Egg, 14 % and 10 % respectively; the lowest mortality recorded in the fourth larval instars and pupae 1.2, 1.65%. Total cumulative % of survival recorded 62.85%. Life cycle completed in 23-47 days. Male dies after few days of mating. Present study revealed that temperature played vital role in the development and growth rate of vittella; highest rate was on 35±1°C but even then its control is possible if management measures could have taken at first and second larval instars which are relatively more vulnerable than other stages; it was also observed that most strong was the fourth larval stage.