摘要：

This chapter explores possible avenues that are available, or may be developed, for the manipulation of natural enemies to improve their effectiveness in controlling pests. The chapter also considers the natural enemies in the context of a rational management program that explores the appropriate use of all available insect control methods. Augmentation of natural enemies to effect suppression of pest populations has received considerable attention over the years. Inundative releases rely mainly on the agents released, not on their progeny, to effect control; whereas inoculative releases rely on an increase in the initial natural enemy populations that can suppress subsequent pest generations. Inundative releases may be timed so that both immediate control and subsequent progeny production contribute to pest suppression. Effective manipulation of natural enemies requires a thorough knowledge of their biology and host associations. Background information may be gained through laboratory studies. However, it is imperative that such data be followed by extensive biological studies in the field. The level of control achieved in an augmentation program may be a function of a myriad of interacting factors. Primary factors include the availability of hosts and host–parasitoid synchrony, the weather conditions during the release of natural enemies involving the effects of environmental factors on foraging, influence of habitat type, chemical pesticide usage, and fitness of laboratory-reared parasitoids.

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