Laboratory evaluation of the insect growth regulator dudim and the plant extract neem oil against Culex pipiens mosquitoes with reference to its side effects on aquatic nontarget organisms.

摘要

The biological effects of the insect growth regulator (IGR), Dudim and the plant extract Neem oil on the developmental stages of Culex pipiens, the dominant mosquito species in Jeddah, Saudi Arabia, were evaluated. The records showed that the response of Cx. pipiens to the test compounds depends on the differential mode of action of the compounds and its effective concentrations. According to IC₅₀ values (concentration which to inhibit the emergence of 50% of mosquito adults emergence), the IGR Dudim (0.0003 ppm) proved to be more effective against Cx. pipiens than the Neem oil (70 ppm). On the other hands, treatment whit IC₉₀ values (concentration which to inhibit the emergence of 90% of mosquito adults emergence) of Dudim (0.0032 ppm) and Neem oil (140 ppm) did not exhibit any market effect on nontarget organisms (naiads Odonata, aquatic hemipterans, aquatic coleopterans) associated with mosquito breeding sites.