ECOLOGY AND RESISTANCE MANAGEMENT FOR BACILLUS-THURINGIENSIS TRANSGENIC PLANTS

Transgenic plants expressing the endotoxin proteins of Bacillus thuringiensis (Bt) will be released for commercial production during this decade. While these plants have a great potential to reduce our dependence on pesticides for insect control, their success will be short-lived if insects rapidly develop resistance to the Bt toxins or if chemical use is needed to control other pests in the same production systems. Ecological studies can play a vital role in the design of strategies that avoid these problems by, for example, identifying key factors in insect life histories that influence the rate at which resistance evolves, validating management models that often make simple assumptions about the population biology of insects, identifying critical insect-plant interactions and determining whether pest control by transgenic plants is affected when the plants are stressed. These points can be illustrated from studies of non-transgenic ecosystems in the areas of host plant resistance, insecticide resistance management and the role of natural enemies in population regulation.