Laboratory Tests of Insecticides on Mosquito Larvae in Polluted and Tap Water

Abstract

A method of preparing a “standard” polluted water with steer manure is described. Emulsion concentrate, water solutions of DDT, Baytex® (O,O-dimethyl O-[4-(methylthio)-m-tolyl]phosphorothioate), malathion, parathion, and carbophenothion were compared as to efficacy against fourth instar Culex pipiens quinquefasciatus Say in polluted and tap water. Statistical analysis indicated that at the LC₉₀ level, DDT, and Baytex performed best in polluted water, malathion was about the same in each medium, and parathion and carbophenothion performed better in tap water.