Cotton in Egypt is subjected to yield and quality losses by arthropod insects. The Cotton leaf worm (CLW), Spodoptera littoralis and the Cotton bollworms, pink bollworm (PBW), Pectinophora gossypiella and spiny bollworm (SBW), Earias insulana cause the greatest part of yield losses resulted from nearly one million feddans cultivated annually.

The high costs of chemical control, continuing economic losses, secondary pest problems and environmental considerations suggest the need for ecologically and biologically oriented cotton pest management strategies. Extensive research on cotton in Middle Egypt has resulted in a broad array of monitoring, biological control, cultural, behavioral, genetic and bioinsecticides that can serve as a base for the formulation of biologicallybased new approach of integrated management of cotton key pests.

In this paper different ways for use of biological control as a reliable, environmentally safe means of pest reduction will be illustrated.

Predictive capabilities of Pheromone- based monitoring system, several simple degree-day models, larval age structure and egg sampling techniques for forecasting spring emergence patterns and population peaks for cotton key pests were studied and coupled to a physiologically-based cotton plant model to examine the insect-plan interactions and timing control applications . Biological control by preservation and augmentation of natural enemies as an important component of pest management practices was involved particularly for Trichogramma species.

Results indicated the cotton key pests could be significantly reduced through area-wide management approaches. In such case, estimating economic impact of a biological control program has to be used on a lot of different indicators including, among others: (1) reduction of the pest population size, (2) increase in crop yield, (3) increase in production, (4) increase in farm revenue or receipts, (5) cost saving, (6) increase in product value, and even (7) social gain (Tesdell, 1990).

In Egypt, four different aspects should be developed for successful biologically-based management program: (1) Identification of optimal species and population for a given biological control program, (2) determine of thermal requirements for parasitoid, pest and host plant, (3) design of prediction models of the parasitoid and(4) proper timing for release.

Integrated biologically-based pest management program was formulated of various biological components of cultural control, natural enemy preservation and augmentation and timing bio-insecticide-based control applications by using certain advanced and integrated prediction models of heat unit, pheromone trap catches, egg sampling and larval age structure. This program successfully met both of short and long term needs of cotton pest management in Middle Egypt.