(BIOCHEMICAL AND MOLECULAR CHANGES INDUCED BY INSECT GROWTH REGULATORS (IGRS) ON SOLITARY AND GREGARIOUS PHASES OF THE DESERT LOCUST, SCHISTOCERCA GREGARIA (ORTHOPTERA: ACRIDIDAE

Abstract

Schistocerca gregaria can change reversibly between the swarming gregarious phase and the cryptic solitarious phase. Gregarious S. gregaria, the most economic damaging phase, aggregate to form migrating swarms in nymph and in adult stages. In this thesis, Insect growth regulators (IGRs), alternative safe control agents, were evaluated. Their toxicity and morphogenetic disturbance on nymphs and adults were recorded. Influences of these IGRs on phase transient were also evaluated. The phenomena of gregarious-solitary-phase-interchange considered to be under specific genetic control; therefore, these genes may act as a new insect control approach and must be taken in highly consideration when synthesis of new controlling tools of S. gregaria. Quantitative and qualitative analysis of protein and DNA were measured. The present investigation is subdivided into some main categories. 1. Toxicological and biological influences of IGRs. Both diflubenzuron and pyriproxyfen induced positive influences in nymphal mortality of S. gregaria in the two extreme phases. However, they are different mode of action they induced highly significant negative influences on adult emergence (p<0.001). Conversely, there was a highly