LABORATORY BIOASSAY OF THE SEX PHEROMONE OF THE FEMALE EASTERN SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

Abstract

AbstractA simple and inexpensive olfactometer based on that of Gaston and Shorey (1964) is described for bioassaying the sex pheromone of the eastern spruce budworm. The number of males buzzing (rapidly beating their wings while circling on the substrate) after the introduction of the sample into the airstream of the olfactometer was used as measure of response. Males held under continuous illumination showed maximum response when 2 to 3 days old. Under natural lighting males showed a circadian rhythm, with peak response shortly after dark and a minor peak in mid-morning. Since per cent response under continuous illumination exceeded the maximum response under natural lighting, it is recommended that bioassays be carried out with 2- to 3-day-old males held under continuous illumination.