The evolution of insecticide resistance: Have the insects won?

While insecticides have greatly improved human health and agricultural production worldwide, their utility has been limited by the evolution of resistance in many major pests, including some that became pests only as a result of insecticide use. Insecticide resistance is both an interesting example of the adaptability of insect pests, and, in the design of resistance management programmes, a useful application of evolutionary biology. Pest susceptibility is a valuable natural resource that has been squandered; at the same time, it is becoming increasingly expensive to develop new insecticides. Pest control tactics should therefore take account of the possibility of resistance evolution. One of the best ways to retard resistance evolution is to use insecticides only when control by natural enemies fails to limit economic damage. This review summarizes the recent literature on insecticide resistance as an example of adaptation, and demonstrates how population genetics and ecology can be used to manage the resistance problem.