Activity of two pyrethroids against blackfly larvae, determined by a simple laboratory technique

Abstract

A simple laboratory technique for determining the activity of two pyrethroids (5‐benzyl‐3‐furyImethyl DL‐cis, trans‐chrysanthemate and 5‐benzyl‐3‐furylmethyl D‐trans‐chrysanthemate) against blackfly larvae (Simulium ornatum) is described. The results showed that the pyrethroids alone or with piperonyl butpxide were of similar activity to Abate (O,O,O',O'‐tetramethyl O,O'‐thiodi‐p‐phenylene phosphor‐othioate) and Dursban (O,O‐diethyl O‐3,5,6‐trichloro‐2‐pyridylphosphorothioate), insecticides of known activity against blackfly larvae. However, the pyrethroids cause rapid larval detachment in running water, and may be of value in controlling these insects when used in conjunction with another insecticide.