Susceptibility difference in two populations of Culex quinquefasciatus Say (Diptera: Culicidae) to three synthetic pyrethroids.

Three synthetic pyrethroids were tested for their efficacy against two populations of the filariasis vector Culex quinquefasciatus under laboratory conditions following the WHO procedure, Emulsifiable concentration and technical grade formulations of deltamethrin (2.5% wp), cypermethrin (1.0% EC) and permethrin (25% EC) were employed on the larvae of the said species collected from Mysore and Mandya. All the three pyrethroids were found to be effective. But among the three, deltamethrin was found to be the most effective and cypermethrin was more efficient than permethrin. Mysore species were found to be more susceptible than the Mandya population to all the chemicals tested though they are separated by hardly 50 km.