الفهرس Only 14 pages are availabe for public view
 |  | from | 202 |  |  |
| | | from | 202 | | |
Abstract
Culex pipiens is one of the main vectors of viral and parasitic diseases in Egypt. The proposed work aimed to study the enzymatic changes associated with the development of resistance in Cx. pipiens larvae treated with certain chemical (methomyl and Malathion) and biological (Bacillus thuringiensis H14) insecticides. Using chemical insecticides showed a decrease in susceptibility of the mosquito larvae with the progressive increase in selection pressure (increase in LC50 dose). In contract there was no significant difference in the susceptibility response to biological insecticides in the successive generations.
Larval bioassay results were supported by those of microplate assays in detection of changes in activities of proteolytic enzymes (trypsin & aminopeptidase) and detoxifying enzymes (non specific esterases, GST and acetylcholinesterase). The recorded changes in the enzymes activities could be used as indications of the multiple previous uses of these insecticides in the field.