EVALUATION OF THE EFFECT OF SOME SELECTED AGRICULTURAL WASTE EXTRACTS ON LARVAE OF CULEX PIPIENS L. (DIPTERA: CULICIDAE)

Abstract

ABSTRACT This study was conducted under laboratory conditions to evaluate the insecticidal efficacy of six plant extracts from two agricultural wastes namely peels of pomegranate and pits of date palm against the 3 instar larvae of Culex pipiens. The mortality percentages increased as the concentrations and exposure time of all tested agricultural waste extracts increased. Based on LC50 values, pomegranate peel petroleum ether extract was the most effective extract, while date palm pits chloroform extract was the least effective one. The tested agricultural waste extracts showed repellent activities against Cx. pipiens females. Phytochemical screening was carried out to detect the effective chemical groups in the tested extracts and was analyzed by GC-MS and HPLC. The addition of non-toxic concentrations of both triton x 100 and tween 20 to different concentrations of the phytochemical extracts synergized their efficacies compared to the phytochemical extract used alone. The most effective phytochemical extracts showed some biological, biochemical and electrophoretic changes in the treated Cx. pipiens larvae compared to the untreated. The phytochemical extracts under investigation were safe to rats up to 4000 mg/kg b.wt. No significant changes were detected in levels of serum ALT, AST, urea, creatinine, acetylcholinesterase and phosphatases of the experimental rat groups administrated orally with 200 mg/kg b.wt. of tested extracts for 21 consecutive days. Ultrastructure studies showed a drastic effect of pomegranate peel petroleum ether extract on most organelles of larvae and adults tissues of Cx. pipiens. rd