Aquatic Bioassay of 11 Pesticides Using Larvae of the Mosquito, Wyeomyia Smithii (Diptera: Culicidae)

摘要

Larvae of the Pitcher-Plant Mosquito, Wyeomyia Smithii, were exposed to solutions of 11 pesticides in 4 chemical groups. Larvae were observed for survival and development (second to fourth instar) during 7 days. With the exceptions of DDT and Resmethrin, the larval mosquito bioassays were as sensitive as fish. Patterns of survival appeared to be affected by persistence of the chemicals. The less persistent chemicals (Malathion, Carbaryl, Permethrin, Phenothrin, and Resemethrin) caused mortality during only part of the bioassays. Larval development was a more sensitive indicator than survival for of the toxicants (Heptachlor epoxide, Methomyl, Propoxur, Permethrin, Phenothrin, and Resmethrin). Signs of intoxication reflected the nervous modes of action of the pesticides.