Response of Cabbage Seed Weevil (Ceutorhynchus assimilis) to Baits of Extracted and Synthetic Host-Plant Odor

The effect of extracted and artificial oilseed rape (Brassica napus ssp. oleifera) odors on the behavioral response of male and female cabbage seed weevils (Ceutorynchus assimilis) was investigated in a wind tunnel. Odor-mediated upwind anemotaxis was induced by leaf extract and its artificial equivalent. Omission of two isothiocyanates from the artificial extract significantly reduced the upwind movement of females. Increasing the wind speed within the tunnel significantly reduced upwind movement in response to the odor of leaf and flower extracts. The artificial baits proved less attractive than simple extracts from oilseed rape. Field trapping confirmed that extracted leaf material was more attractive than artificial equivalents.