Abstract: Based on detailed studies of Heliothis armigera foraging behaviour in cotton field, its population dynamics and simulation model of cotton growth and development, a management system has been established. The latest research achievements in this area are combined in the system. The dynamical effects of the 2nd and 3rd generations of cotton bollworm on the growth and development of cotton plant can be given separately and compositely. As a management system, it can produce suitable schemes of artificially removing squares in different egg levels of the 2nd generation. And, by comparing the final yields of cotton in different spraying tactics, the optimal one can be given. The overcompensation mechanism in cotton plants has been especially emphasized in the system. Field experiments had shown that artificially removing early squares can increase cotton yields, and if without or within a certain extent of the damages of plant growing points, the foraging by cotton bollworm had same effect, but with less degree. The system can differentiate clearly the effect of these two different "stimulations" on cotton growth and final yields.

Key words: Heliothis armigera, Cotton, Overcompensation, Management system