Immunological and Histopathological Effect of Plant Extract on Schistocerca Gregaria

Abstract
The desert Locust, Schistocerca gregaria (Forsk) is one of the serious pests attacking vegetables and wide varieties of other field crops in Egypt and other different countries.The present study was also extended to conduct the insecticidal effect of the most potent extracts Citrullus colocynthis, and Guayacum officinalis extract post formulation on S. gergaria larvae. The present study has been conducted to investigate the effect of plant extract on differential and total haemocyte counts and midgut histopathologiocal changes of S. gregaria Four types of haemocytes were characterized; prohaemocytes (PRs), plasmatocytes (PLs), granulocytes (GRs) and oenocytoids (OEs). The percentage of PRs decreased in insects fed on leaves treated with Citrullus colocynthis, and Guayacum officinalis plant The percentage of PLs increased, while the percentage of GRs decreased in all tested insects treated. The percentages of oenocytoids (OEs) increased in insect fed treated compared with control. Results indicated that THCs of insects fed on leaves treated significantly decreased in all insects treated. also, showed highly histopathological disturbances in the midgut and body wall cells of this pest. Among the most recorded observations are vacuolation, destruction of the cells. DOI: 10.20448/journal.504/2016.3.1/504.1.1.7