Abstract
Plant volatile organic compounds (VOCs) can influence the behavior of insects but distance and contact effects are rarely distinguished. We aimed to identify VOCs that mediate attraction and oviposition behaviors of the cabbage root fly, and to distinguish whether their effect applies at distance or at contact. Headspace collections of host-emitted VOCs were performed and analyzed in combination with electro-antennogram detection. The behavioral effect of the electrophysiologically-active VOCs was assessed in behavioral experiments. We show that VOCs act mainly when in mixtures, and have effects either at distance or at contact, but not both.