Reactions of Insects to the Olfactory Stimuli from the Components of an Insecticidal Spray

Abstract

Two kinds of equipment for measuring the reactions of insects to the olfactory stimuli provided by some common components of insecticidal sprays are described. One of these, consisting of a T-tube carrying a current of odorous air across the top and admitting insects up the stem, is new, can be used in the field, and gives rapid and reproducible evaluations. Tests with several species of Diptera showed that technical DDT, diesel fuel oil, and an auxiliary solvent containing methylated naphthalenes are all strongly repellent or contain strongly repellent components. Related species gave similar results with the two kinds of equipment. House-flies (Musca domestica L.) resistant to DDT were less sensitive than normal house-flies. The implications of these findings are discussed.