LAUSR

The Eurasian spruce bark beetle, Ips typographus (IT), is considered the most destructive insect pest of spruce forests in the Palaearctic region. Its control is based on a range of phytosanitary measures, insecticide treatments targeting the tree trunks, and pheromone trappings. Essential oils (EOs) from aromatic plants have been recognized as ecological alternatives to synthetic pesticides. In this study, EOs from plants in the Lamiaceae family (Origanum vulgare, Thymus vulgaris, Hyssopus officinalis and Mentha × piperita) and the Apiaceae family (Pimpinella anisum and Foeniculum vulgare) were studied for insecticidal and repellent effects against IT. EOs chemical composition was analyzed with gas chromatography mass spectrometry. IT adults were exposed to different concentrations of EOs, and their effects were recorded 2–96 h post-treatment. Significant differences in biological activity were observed, and the greatest insecticidal effect was detected for O. vulgare, T. vulgaris, and P. anisum; but O. vulgare EO was significantly more toxic at all doses or exposure times. Repellency index (RI) varied among the EOs and depended on dose and exposure time. At doses of 0.077‒0.219 µl/cm2, the RI increased until 4‒6 h post-treatment; after that period, it decreased. Pimpinella anisum, O. vulgare, and T. vulgaris EOs showed significantly higher repellent effects compared to F. vulgare and H. officinalis EOs. Mentha × piperita EOs exhibited neither repellent nor insecticidal activity against IT. To our knowledge, this is the first time that EOs biological activity against IT was studied.