ELECTROANTENNOGRAM RESPONSES OF APHIDS TO THE ALARM PHEROMONE (E)‐β‐FARNESENE

Electroantennograms (EAGs) were recorded to investigate which sensilla on the antenna of Acyrthosiphon pisum and Megoura viciae are able to perceive the alarm pheromone (E)‐β‐farnesene. The two primary rhinaria on the 6th and 5th antennal segment were shown to be the main receptors, although the secondary rhinaria on the 3rd segment might also respond: the latter are probably far less sensitive than the primary rhinaria.