Sex-related perception of insect and plant volatiles in Lygocoris pabulinus

We recorded electroantennograms of male and female Lygocoris pabulinus ante nnae to 63 insect and plant volatiles. EAGs were between 100 and 500 mu V. Overall, male EAGs were about twice the size of female EAGs. In both sexes, largest EAGs were recorded to (E)-2-hexenyl butanoate and (E)-2-hexen-1-ol . Response profiles were similar in both sexes. However, male antennae were more sensitive to a number of esters, especially the butanoates and pentan oates. Female antennae were more sensitive to nine of the 19 plant volatile s, i.e., to hexan-1-ol, heptan-1-ol, 1-octen-3-ol, 2-heptanone, (R)-carvone , linalool, geraniol, nerol, and methyl salicylate. Sexual differences in r esponses suggest that males are more sensitive to insect-produced pheromone -type compounds, whereas females are more sensitive to plant compounds for their orientation towards oviposition sites.