Attraction during flight of scolytids and other bark- and wood-dwelling beetles to volatiles from fresh and stored spruce wood

Attraction of scolytids and other bark- and wood-dwelling beetles to volatile constituents of Norway spruce (Piceaabies (L.) Karst.) was studied in field experiments in central Sweden. The volatiles were released from chips of newly cut spruce stems as well as from stems stored over winter. These host materials were kept in cylinders covered on both ends with fine nylon mesh. Attracted insects were caught in barrier traps. The composition of volatile constituents of wood samples was determined using gas chromatography. Hylurgopspalliatus (Gyll.), Hylastescunicularius Er., Ipstypographus (L.) (Scolytidae), and Glischrochilusquadripunctatus (L.) (Nitidulidae) were particularly attracted to stored spruce wood. Trypodendronlineatum (Oliv.) (Scolytidae) and Pityophagusferrugineus (L.) (Nitidulidae) were only attracted to stored wood. There were indications that Tomicuspiniperda (L.) and Hylastesbrunneus Er. (Scolytidae) preferred fresh wood. Chemical analyses revealed that during storage ethanol and acetaldehyde increased considerably in two out of the five examined tree stems.