Substrate preference for eggs laying pattern and Modification of larval rearing unit of Helicoverpa armigera (Hubner)

Abstract

The fertile egg production was observed from day of 5th to day 11th having two peaks on the 5th and on the 10th day of the egg laying period. The overall mean fertile egg production per female was 1173.25 and sterile egg production per female was 298.50. The maximum sterile eggs were laid on day 13th with 46.5 numbers. Eggs were found on different substrates such as cotton cloth cover, hung vertically cotton cloth, cotton swabs and inner layer of oviposition cage. There were 54 per cent survival in tooth-picks and 46 per cent in without tooth picks which was statistically significant. Male and female pupal weight was 0.378gms and 0.368gms in tooth-picks trays while it was 0.357gms and 0.361gms in without tooth picks.