LARVICIDAL OILS MODIFY THE OVIPOSITION BEHAVIOR OF CULEX MOSQUITOS

Larvicidal oils were shown in laboratory and field studies to be repel lent to ovipositing Culex quinquefasciatus, Culex tarsalis and Culex s tigmatosoma. In laboratory two-choice oviposition assays, open cups in which water was treated with Golden Bear 1356 and 1111, Rodspray MFST S, and Orchex parafinic oil received fewer Culex quinquefasciatus egg rafts than did untreated cups. Cups in which water was treated with Go lden Bear 1111 and Rodspray MFSTS also received reduced Culex tarsalis oviposition when compared to untreated cups. Cups treated with Golden Bear 1111 or Rodspray MFSTS received fewer egg rafts than untreated c ups in Culex quinquefasciatus paired oviposition tests for three to se ven days post-treatment. In two field studies, Golden Bear 1111 and Ro dspray MFSTS reduced egg deposition by Culex stigmatosoma and Culex qu inquefasciatus for at least seven days posttreatment at operational ra tes.