الفهرس 
A-Family Flaviviridae (genus FlavivirusOnly 14 pages are availabe for public view
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Abstract
Culex pipiens is a worldwide mosquitoes causing nuisance and transmitting many dangerous diseases. In Egypt, it is the main vector of filarial worm Wuchereria bancrofti as well as Rift valley fever virus.
Insecticides overuse led to several ecological drawbacks over the past years. The toxicity, development of resistance phenomenon and the residual effects of these insecticides are the main concern of scientists. The urging need for developing environmental friendly insecticides is rising.
Botanical insecticides are one of the successful alternatives as recorded by studies on plant-insect interaction. They are safe, specific, biodegradable, eco-compatible components. Therefore, this study aimed at evaluation of the Insecticidal and genotoxic Activities of three aromatic substances; eucalyptus oil , clove oil and rose water on Culex pipiens adults and larvae.
The chemical composition of essential oils were determined by gas chromatography/mass spectrometry (GC/MS) analysis .The main components of clove essential oil were Eugenol(88.08%) , Eugenolacetate(3.40%) and b-Caryophyllene(3.24%).The main components of eucalyptus essential oil were 1, 8-eucalyptol(46.76%) and D-Limonene (9.61%) . The main components of rose essential oil were nerol(20.88%), Citronellol(18.05%) and Geraniol (10.42%).
Fumigation bioassay was performed on Culex pipiens adults, eucalyptus oil has the highest toxicity index (LC50 :0.108%) and rose water has the lowest toxicity (LC50: 0.732% ) after 24h.
In larval bioassay of Culex pipiens eucalyptus oil has the highest toxicity index (LC50 : 0.014%) and rose water has the lowest toxicity (LC50: 0.119%) after 48h.
The effects of three aromatic substances on the larval duration, pupation percent, pupal duration, adult emergence percent were determined, The induced malformed larvae, pupae were recorded and photographed.
The present study showed effect of tested aromatic substances on activities of Glutathione peroxidase (GPx) ,catalase and superoxide dismutase (SOD). The activities of GPx are significantly inhibited (P<0.05) compere to control and gradually decreased with the increasing concentrations of tested aromatic substances on Culex pipiens larvae. In Culex pipiens adult the activities of GPx are increased than that of the control and gradually decreased with the increasing concentrations, except in rose water the GPx activity is gradually increased with the increasing concentrations. In high concentration of eucalyptus oil there is no significant differences are found as compared to control (p>0.05).
The activities of catalase are increased about two fold as compared to control in low concentrations (P<0.05) but there is no significant differences were found as compared to control in high concentrations (P>0.05) in both Culex pipiens adult and larvae.
In Culex pipiens adult the activities of SOD enzyme are increased than that of the control and gradually decreased with the increasing concentrations after exposure to clove oil and rose water.In case of eucalyptus oil at low concentration there is no significant difference (P>0.05) but, in high concentration there is significant decrease in enzyme activities (P<0.05).There is no significant differences are found on the activities of superoxide dismutase in culex pipiens larvae (p>0.05).
The genotoxic effect of tested aromatic substances was evaluated by comet assay as a measure of DNA strand-break damage. There was dose-dependent increase in DNA damage as evident by increase in the Comet parameters i.e. tail length (Px) and tail DNA (%), DNA % in head and % of DNA damage as compared with control.
The aromatic substances selected showed a promising potentiality to be used as green insecticides in controlling Culex pipiens adult and larvae.
Key words: Culex pipiens , eucalyptus oil , clove oil , rose water, GPx ,catalase and SOD.