الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
The current research was undertaken to investigate the following topics:
1) the toxicity and biological activity of sublethal concentrations of five non-conventional insecticide, having different mechanisms of toxicity action, against C. maculatus; 2) the residual activity of tested insecticides on development of C. maculatus at different periods of storage of treated-cowpea seeds; 3) the potential effects of sublethal concentrations of tested insecticides on the oxidative status and antioxidant biomarkers in insects; 5) the fumigant toxicity and biological activity of five essential oils against C. maculatus; the major compounds in each essential oil have been also identified. The selected non-conventional insecticides were: abamectin, ememectin benzoate, imidacloprid, indoxacarb and spinosad. The contact toxicity assay showed that emamectin benzote and ndoxacarb were the most toxic based on 24 h-LC50. The sublethal effects of insecticides showed that abamectin and emamectin were the most effective in reducing ovposition rate and F1-progeny of C. maculatus. The residual activity of abamectin continued for up-to 90 days after storage treated seeds. The data also showed that insect exposure to LC50 of emamectin benzoate and imidacloprid significantly increased MDA, a biomarker of oxidative stress; whereas the antioxidant marker, SOD, was decreased in all insecticides treatments. In contrast, glutathione reduced and glutahione peroxide levels significantly increased in all treatments comparedto the control. On the other hand, the fumigant toxicty of five essential oils from tea tree, rosemary, peppermint, geranium and eucalyptus plants were also evaluated. The LC50-data showed that peppmint and tea tree oils were the most toxic against insect adults. The sublethal concentrations (LC20 and LC50) of both peppermint and geranium showed significant effect in reducing ociposition rate and F1-progeny compared to the control.