8th Int. Symp. on Insect-Plant Relationships

Abstract

Phoracantha semipuncata F., a specific bark borer of Eucalyptus trees, causes significant damage in the stands in southern Portugal. The aim of this study was to test the hypothesis that the odour released by the host tree plays an important role in the host-finding vehaviour of this nocturnal insect. The field results show that both males and females can locate freshly cut E. globulus material from a distance, probably in response to the odour released, perceptile by the insect as revealed by in the recording of electro-olfactograms (EAG). Although the EAG results shoulf be regarded as preliminary, it is clear that this antennal olfactory system is selective for the compounds present in the odour blend of host trees and screening their EAG activity will tell us more about the olfactory stimulus involved in host-finding behaviour.