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The post‐hibernating adults of the apple blossom weevil, Anthonomus pomorum (L.), show preferences for certain cultivars in mixed apple tree orchards. The degree of infestation of various cultivars was positively correlated with the density of flower buds at a comparable phenological stage, but the numbers of collected beetles were not linearly proportional to the bud density of different cultivars. Hence other possible factors, namely chemical ones, were investigated. Chromatographic analysis of apple tree bud emanations showed that volatiles from two different apple cultivars that show a different attractiveness to the beetles, differed in chemical composition. Several less volatile components of the bud emanation bouquet elicited antennographic responses in both male and female antennae. Four terpene hydrocarbons, namely 3‐carene, perillene, caryophyllene and (E,E)‐α‐farnesene, were identified among the components that produced distinct electrophysiological responses in the antennae. These findings support a hypothesis that the adult weevils use chemical cues for olfactory discrimination during host‐searching behaviour.

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