Bacillus thuringiensis: Natural and Recombinant bioinsecticide Products

Worldwide sales of Bacillus thuringiensis (Bt) dwarf those of any other biopesticide product. Annual sales in the early 1990s were estimated at $100 million, accountmg for l-2% of the global insecticide market (, ). The largest masrket for Bt-based bioinsecticides, estimated by van Frankenhuyzen () to be ~60% of the total Bt market m 1990, is in the protection of vegetable and horticultural crops from lepidopteran pests. The remainder of the Bt market Includes applications for the control of forest pests (), particularly in North America, dipteran pests that act as vectors of human diseases (), lepidopteran pests on cotton, and coleopteran pests on solanaceous crops, Lambert and Peferoen () and van Frankenhuyzen () provide fine historical overviews of the development of Bt as a commercial bioinsecticide. Over the past 15 yr, much progress has been made in understanding the molecular and genetic basis of Bt insecticidal activity. The recent review by Cannon () covers many aspects of Bt molecular biology. In this chapter, we will highlight advances in the development of improved btoinsectrcide products based on recombinant or genetically modified strams of Bt.