ELECTROANTENNOGRAMS FROM SPRUCE BUDWORM MOTHS (CHORISTONEURA FUMIFERANA) (LEPIDOPTERA: TORTRICIDAE) OF DIFFERENT AGES AND FOR VARIOUS PHEROMONE CONCENTRATIONS

Abstract

Abstract An electroantennogram (EAG) technique, which indicates electrochemical activity in a whole antenna, was used to study sex pheromone reception in spruce budworm moth antennae. For both males and females the EAG exhibited a phasic depolarization, reaching maximum near the end of a puff stimulation, followed immediately by repolarization which was prolonged by increasing amounts as the source concentration of the pheromone was increased. The dose–response curves for both sexes were sigmoid in shape, but they indicated that female antennae have a higher threshold and a lower peak response than that of males. Antennal response changed with age, being a regular increase and decrease for females and irregular for males.