Evaluation of Two Insect Growth Regulators (IGRS) As a Feed- Through Treatments against Adults of Culex pipiens L. mosquito | ||||
| Alexandria Science Exchange Journal | ||||
| Article 8, Volume 31, OCTOBER- DECEMBER - Serial Number 4, October 2010, Page 365-370 PDF (381.79 K) | ||||
| Document Type: Original Article | ||||
| DOI: 10.21608/asejaiqjsae.2010.2332 | ||||
 View on SCiNiTO | ||||
| Author | ||||
| Hossam EL-Din M.Zahran* | ||||
| Department of Entomology Faculty of Agriculture (El- Shatby) Alexandria University, Egypt | ||||
| Abstract | ||||
| This study was carried out to evaluate the biological effects of two IGRs (Match® and Baycidal®) on Culex pipiens mosquitoes when fed the adults on sugar solution mixed with 0.1, 0.5 and 1 ppm of each compound. Some delayed effects of these treatments were also determined. The results indicated that the use of each of the tested IGRs caused a reduction in the blood-feeding activity of mosquito female when compared with the controls. The reductions were 18.2, 22.7 and 31.8% by using Match and 25, 27.3 and 36.3% by using Baycidal®, respectively, at the tested concentrations. The reduction in biting activity of mosquito females may lead to a decrease in the number of fully engorged females and accordingly affect their reproductive capacity of mosquitoes. The use of Match® and Baycidal® at the tested concentrations caused a marked prolongation in the time needed for blood meal digestion by C. pipiens females. The prolongation percentages were 44.4, 48,8 and 55.5% by using Match and 51.1, 55.5 and 62.2% by using Baycidal®, respectively. Also, treatments caused a reduction in the reproductive capacity. The maximum decreasing in egg production was 30.3% at concentration of 1 ppm of Match®. The result showed that the treatment by Baycidal® at 0.1, 0.5 and 1ppm led to a remarkable reduction in the egg production by 61.9, 66.1 and 69.2%, respectively and also the hatchability was reduced in the treated females. Subsequent study was carried out to investigate the delayed effect of IGRs Match® and Baycidal® on the hatched larvae. The result showed that the larval development was gradually inhibited by 17.8, 49.8 and 92.7% by using Match® at 0.1, 0.5 and 1 ppm, respectively. On the other hand the larval development was completely inhibited after the treatment of adults fed by 0.5 and 1 ppm Baycidal®. The larvae developed till the 2nd instar but completely failed in molting to the 3rd instar. Subsequent study was conduced on the effect of Match® and Baycidal® on the longevity of the survived mosquito adults that, the records showed that no significant differences in the mean of adult longevity between treatments and control. | ||||
|
Statistics Article View: 201 PDF Download: 311 |
||||
