ABSTRACT
Bt-based formulations have been developed and used commercially for several decades in various parts of the world. These biopesticides have been primarily applied in forestry in vegetable gardens, and in mosquito-eradication programmes (Hofte and Whiteley 1989). However, due to problems such as poor field stability, narrow toxicity spectrum and slower toxicity (when compared to chemical insecticides), widespread use of these environmentally-safe biopesticides is rather limited.
