a1 Monsanto India Limited, Ahura Centre, 5th Floor, 96 Mahakali Caves Road, Andheri (East), Mumbai 400 093, India
a2 Monsanto Research Centre, No. 44/2A, Vasanth's Business Park, Bellary Road, NH-7 Hebbal, Bangalore 560092, India
a3 Monsanto Company, 800 North Linderbergh Boulevard, St Louis, Missouri 63167, USA
A study was carried out to develop a diet for mass rearing of the pink bollworm Pectinophora gossypiella (Saund.) and optimize bioassays for testing the bollworm's sensitivity to two insecticidal proteins from Bacillus thuringiensis (Bt). A P. gossypiella colony was established in the laboratory from field collections and its developmental biology was compared on various test diets. Larvae reared on a diet of cottonseed and chickpea flours for the first 10 days and subsequently on pieces of okra attained rapid growth and development. This two-phase diet has been used for successful laboratory rearing of 51 generations of the bollworm. Neonates were found to be sensitive to both the Bt proteins Cry1Ac and Cry2Ab2, which are produced by the transgenic Bt cotton products Bollgard™ and Bollgard II™.
(Accepted May 25 2009)