TEMPERATURE STRESS EFFECT ON THE DESERT LOCUST, SCHISTOCERCA GREGARIA USING BIORATIONAL COMPOUNDS

Desert Locust, Schistocerca gregaria (Forskål), is one of the important insect pests worldwide. Chemical insecticides proved effective in controlling these locust, but with bad ecosystem impact. This study evaluated the temperature stress on biorational insecticides against Schistocer ca gregaria . Newly moulted 5 th instar nymphs of the desert locust were feed on clover leaves treated with LC 50 of Azadirachtin, Rotenone, Sabadilla and Limonene. Also, anti-hormonal effects of Precocene II showed decrease in protein; carbohydrate and lipid of haemolymph contents after 24hrs treatment of 5 th nymph instar with these biorational insecticides. The higher LC 50 was 3.4 obtained after treating 5 th nymphal instar with azadirachtin, lower LC 50 was 4.2 caused by lim-onene with LC 90 of 15.2 & 28.2% respectively. These biorational insecticides affected protein, lipid and carbohydrate of 5 th nymphal ones, added by temperature marked stress. Supernumerary (extramoulted) nymph emerged after treating 5 th nymph instar with Precocene II. Precocene II caused nymph malformations at high concentration (33.3%; 1000ppm) and at low concentration (14.2%; 50ppm), and blocked adult emergency with increased concentrations.