摘要：Following World War II, pest control largely shifted from a biological discipline to a chemical one. Unilateral dependence on pesticides has also resulted in concentrating effort on developing high-yield crop varieties with disregard for loss of characters for tolerance or resistance to pests. The broad ecological dictum of considering the whole interacting system was generally ignored and, thus, the importance of natural enemies and the plant's own factor for resisting pests. Excessive reliance on pesticides for the last three decades has destroyed natural enemies and caused some pests to develop resistance to pesticides. Consequently, the use of frequent treatments with increasing dosages was adopted in an effort to control pests. This development, however, increased production costs of many crops without alleviating the problem (Huffaker and Smith). The rise of energy and pesticide costs combined with growing ecological and social concern about excessive pesticide use have encouraged scientific and public attention to initiate coordinated research on agricultural pests that consider the biological, cultural, and ecological aspects of controlling pests. The United States International Biological Program (IBP) initiated in 1971 with the cooperation of the National Science Foundation, the Environmental Protection Agency, and the U.S. Department of Agriculture, and 18 land-grant universities has set the foundation for the development and implementation of coordinated pest control programs which are more efficient and less harmful to public health and the environment. Direct techniques and methods of control utilized in integrated pest management (IPM) include: crop plant resistance, biological control, cultural control, pesticide use, attractants and repellants, and growth regulation. In addition to the direct pest control methods, collecting the necessary information by monitoring or sampling the pest population and its principal natural enemies at appropriate times of the year is required for effective management decisions. Through monitoring and short-term weather prediction it was possible in 1976 to reduce insecticide treatments of cotton from 10 to two applications per year (Huffaker and Smith). In general, IPM uses the best combination of all known control techniques and concentrates on the plants themselves rather than the pests.
