A simple and low-cost laboratory rearing technique for pink bollworm, Pectinophora gossypiella (Suanders) (Lepidoptera: Gelechidae) using detached green bolls of cotton

摘要

A simple and inexpensive method that uses freshly excised green bolls (10 d old) of cotton (Gossypium hirsutum L.) is developed for laboratory rearing of pink bollworm, Pectinophora gossypiella (Saunders). The adult females of pink bollworm preferred to lay eggs on the bracts and sometimes also on the rind of bolls, either singly or in a group of 2-3 eggs. The larvae fed and pupated within the bolls itself. The developing larvae can be removed at any stage of their development for morphometric studies, conducting bioassays, etc. The newly formed pupae can easily be removed and maintained till adult emergence. The egg hatching and adult emergence were 89.94 +/- 3.61% and 92.32 +/- 2.34%, respectively with a mean fecundity of 203.73 +/- 38.83 per female and a mean generation time of 34.43 +/- 0.61 days. All the biological parameters of pink bollworm reared by this method were reasonably comparable with literature reports on its rearing using different natural as well as artificial diets. The insect raised by this method retained its ability to infest field grown cotton. We could successfully raise up to five generations of pink bollworm by this method with the input of one labourer. This method is easily applicable and less expensive, and it would be highly useful in understanding the pink bollworm phenology mediated through alterations and or aberrations in nutritional status of its host crop i.e. cotton.