The role of energy flow in biological control trophic interactions for organic cotton production in Egypt

Abstract Background Energy flows in most food chains in the agroecosystem are crowned with beneficial natural enemies including different species of predatory and parasitic insects, birds and animals. They are utilized in organic and IPM cotton production to replace the conventional insecticides usually applied in cotton production. Results Natural populations of six coccinellids, five staphylinids and two carabids (Coleoptera), three anthocorids and three reduviids (Heteroptera), five syrphids (Diptera, three labidurids (Dermaptera), two chrysopids (Neuroptera) and one thripid (Thysanoptera) species were manipulated in Egyptian clover to aggregate in seed production stripes (stripe technique) adjacent to and across the cotton fields during April–May, 2022. These 30 predatory species represent 112 energy flow routes in food chains preying on tetranychid mites, aphids, thrips, whiteflies and cotton leaf worm attacking cotton plants during vegetative growth stage beginning from April to May 2022. High populations of these predators develop along the clover season (November–May) on different pests where no insecticide applications occur. They aggregate in the flowering clover stripes left for seed production feeding on nectar, pollens and remaining pests. By dryness of the clover stripes, populations of all these predatory species abandon the clover, migrating outwards into the adjacent cotton or corn fields showing an excellent high protection against cotton pests suppressing their populations far away under the level of economic threshold damage during vegetative growth stage. Dressing cotton seeds with Bacillus amyloliquefaciens as antagonist protects the seedlings from soil-borne diseases. Insect pheromone traps detected the first appearance of the pink bollworm, Pectinophora gossypiella (Saund.) moths, the cotton bolls are attacked also by the spiny bollworm, Earias insulana (Boisd.). The egg parasitoid Trichogramma evanescens (West.) was released in 6 successive releases to guide the energy flow in favor of the parasitoid by getting it from egg contents of these two pests, which resulted in high protection of cotton bolls. This study aims better understanding of biodiversity and the routes of energy flow among the complex net of food chains governing the bio-dynamics in the Egyptian agroecosystem, which enabled the development of the present strategy to completely abandon application of the conventional insecticides and chemical fertilization for organic cotton production in Egypt. Conclusion The study is an approach contributing to improvement of the agroecosystem and production of healthy crops.