Abstract

In olfactometric experiments a wingless adult of Sitobion avenae was attracted by odours of a wingless adult of Rhopalosiphum padi feeding on a wheat plant. When the stimulus consisted of either a wingless R. padi without plant material or a wheat plant that had previously been infested by a wingless R. padi, the response by S. avenae was not significant, suggesting that recognition is due to volatiles produced by the combination of an aphid and a plant.