Highlights: Prinobius myardi is a wood borer considered a major threat for Mediterranean oaks, especially Quercus suber and Q. ilex; We performed electroantennographic bioassays to assess olfactory sensitivity of P. myardi to synthetic plant volatiles; P. myardi exhibits a broad sensitivity to common tree volatiles, including those emitted by oaks (α-pinene and β-pinene) or non-host volatiles (1,8-cineole).
Prinobius myardi Mulsant is a wood borer implicated in the decline of Mediterranean oaks, especially Quercus suber L. and Quercus ilex L. Plant volatiles play an important role in plant-insect interactions, and electroantennography (EAG) is an effective tool for exploring the electrophysiological activity of host plant volatiles on insects. To improve our understanding of the olfactory sensitivity of P. myardi, we recorded EAG responses to 20 tree volatiles, and analyzed the dose-dependent response to five doses (10–4:1 to 1:1 v/v) of the three most EAG-active compounds. Antennae of P. myardi responded to 13 chemicals, mainly monoterpenes and green leaf volatiles, with the strongest EAG responses being observed with β-pinene, (+)-α-pinene and 1,8-cineole. Dose–response profiles showed positive dose-dependent responses for all three compounds. Our results suggest a broad sensitivity of P. myardi to common tree volatiles, particularly some host-related compounds and volatiles associated with wounded trees; the olfactory recognition of ratios of these compounds could play a role in host selection by P. myardi.