Toxicological and histopathological studies of Boxus chinensis oil and precocene II on larvae of the red palm weevil Rynchophorus ferrugineus (Oliver) (Coleoptera : Curculionidae )

Two natural biopesticides, (Boxus chinensis oil and precoceneII) were tested against 10 days-old larvae of the red palm weevil, Rhynchophorus ferrugineus. The two biopesticidse had toxicological and pathological effects on Rh. ferrugineus larvae. The toxicity effect of B. chinensis was more than precoceneII against Rh. ferrugineus. In order of toxicity the LC50 of B. chinensis was 0.68% while the LC50 of precoceneII was 1.36%. On the other hand the mid-gut tissues of the 10days old larvae were exhibited different histopathological lesions due to effect of B. chinensis. The alterations included analyze and destroyed of epithelial cells, vaculation of cytoplasm and dissolve of nuclei of the epithelial cells.