The cypress bark beetle, Phloeosinus aubei (Coleoptera, Curculionidae, Scolytinae) prefers to build breeding galleries in decaying host trees. However, volatile cues specific to decaying or actively infested trees have not yet been reported. Any such information would be useful for the management of this invasive, wood-boring species that has become established across Europe in the temperate zone and is now a key pest of ornamental Cupressaceae in nurseries and urban landscapes. Our objective was to reveal key components in host volatiles specific to stressed trees, which could be potential signals for the pest of its suitability for colonisation. Volatile profiles of arborvitae, Thuja occidentalis ‘Smaragd’ suffering from either dehydration or fresh infestation of P. aubei was collected and compared to that samples from healthy control trees. Analyses of volatiles by gas chromatography coupled to an electroantennographic detector revealed substantial differences between healthy, dehydrated and infested trees. Structural elucidation of the major antennally active components revealed that both α-pinene and α-thujene were prevalent in the volatiles of infested trees, whilst α-thujone was the major component in volatiles of healthy trees. In volatiles collected from trunks housing fresh P. aubei female nuptial chambers, sharp increases of β-pinene, myrcene, limonene, and p-cymene were noticed, alongside trace amounts of camphene and fenchene. Volatiles collected from fresh frass showed a similar profile, but with a somewhat smaller amount of limonene. Fenchone was present in each type of volatiles, however, only in low amounts. Further studies should be directed to reveal the behavioural role of these components, which could be helpful in developing kairomone-based techniques for monitoring the flight of the pest in stands of scale-leafed trees.

柏树皮甲虫Phloeosinus aubei（鞘翅目、象甲科、小蠹亚科）喜欢在腐烂的寄主树上建造繁殖廊。然而，尚未报道针对腐烂或活跃感染的树木的挥发性线索。任何此类信息都将有助于管理这种入侵性蛀木物种，该物种已在欧洲温带地区建立，现在是苗圃和城市景观中观赏柏科植物的主要害虫。我们的目标是揭示受压树木特有的宿主挥发物的关键成分，这可能是害虫适合定殖的潜在信号。遭受脱水或新鲜侵染的侧柏、侧柏“Smaragd”的挥发性特征收集P. aubei并与健康对照树的样本进行比较。通过气相色谱法和触角电检测器对挥发物进行分析，揭示了健康、脱水和受感染树木之间的显着差异。主要触角活性成分的结构解析表明，α-蒎烯和α-侧柏烯在受侵染树木的挥发物中普遍存在，而α-侧柏酮是健康树木挥发物中的主要成分。从存放新鲜P. aubei 的树干收集的挥发物中在雌性婚房中，β-蒎烯、月桂烯、柠檬烯和对伞花烯的含量急剧增加，同时还发现微量的莰烯和茴香烯。从新鲜草中收集的挥发物显示出类似的特征，但柠檬烯的含量稍少。然而，每种类型的挥发物中都存在小茴香酮，但含量很少。进一步的研究应该旨在揭示这些成分的行为作用，这可能有助于开发基于利它素的技术来监测鳞叶树中害虫的飞行。