Kerchev I.A. 2019. [The design of an olfactometric trap for dendrophagous insects, as tested by Polygraphus proximus Blandf.] // Euroasian Entomological Journal. Vol.18. No.1: 11–15 [in Russian, with English summary].
Institute of Monitoring of Climatic and Ecological Systems, Russian Academy of Sciences, Siberian Branch, Akademichesky Prosp. 10/3, Tomsk 634055 Russia.
ABSTRACT. The construction of a trap for bark beetles is proposed, which allows one to conduct olfactometric studies without the presence of dispensers with an aggregation pheromone. The peculiarity of the trap is the modification of the barrier and parts containing attractants in comparison with the available commercial analogs. The trap consists of plastic barriers attached to a 110 mm diameter PVC cylinder, to which a funnel with a detachable receptacle for insects is attached at the base. As a source of odorant, a piece of tree trunk and overwintered insects are placed inside the plastic cylinder. The trap has side openings for transpiration of synthesized volatiles, covered with a metal mesh to prevent the escape of beetles. Under laboratory conditions, a test was conducted on five traps, three of them containing Siberian fir logs which were colonized respectively the first with 10 males, the second with 10 females and the third with 10 pairs of Polygraphus proximus; in the fourth trap was a piece of fir log without insects, the fifth trap represented a control (a trap without logs and any insects). In the same room, 300 bark beetles were released to assess the attractiveness of the traps. Traps are arranged by their degree of catchability in descending order: with segments, three inhabited by pairs, females, males, fourth with fir log and fifth as control trap. The proposed trap design, due to the ease of assembly and availability of materials, is ideal for use in the field to study the pheromonic communication and the attractiveness of various metabolites produced by associate insects after penetrating plant tissues. The results of laboratory tests are confirmed by observations of the peculiarities of tree colonization in natural conditions during the spring swarming flight of the bark beetles.
KEY WORDS: trap, olfactometry, Polygraphus proximus, communication, pheromones, bark beetles.