The olive fruit fly, Bactrocera oleae (Rossi), is a key pest of the olive crop, whose control relies mostly on the use of insecticides. Plant peptides may represent a more environmentally-friendly tool to manage olive fly, due to their recognized role to activate and/or prime plant defence responses against pests. In this work, behavioural experiments (no-choice and two-choice) and analysis of volatile compounds were carried out to evaluate the impact of the exogenous application of the peptide systemin to olive tree on olive fly infestation, and to elucidate its mode of action to prime plant defence. The treatment of olive branches with 10 nM systemin showed to confer protection against olive fly, by reducing significantly the ovipositions (up to 3.0-fold) and the number of infested fruits (up to 2.9-fold) when compared to non-treated branches. This protective effect was even detected in neighbouring non-treated branches, suggesting the ability of systemin to trigger plant-to-plant communication. The deterrent activity of the primed olives was associated with the emission of the volatiles 2-ethyl-1-hexanol, 4-tert-butylcyclohexyl acetate and 1, 2, 3-trimethyl-benzene, which were negatively correlated with oviposition and fly infestation. Systemin has also showed to trigger the biosynthesis of specific volatiles (esters) in olives in response to fly attacks. Overall, the observed protection conferred by systemin against olive fly is likely due to the emission of specific volatiles that can act as a defence and/or as signalling molecules to upregulate the plant defence response. Thus, systemin represents a novel and useful tool to manage olive fruit fly.

橄榄果蝇，Bactrocera oleae (Rossi)，是橄榄作物的主要害虫，其防治主要依靠杀虫剂的使用。植物肽可能代表一种更环保的管理橄榄蝇的工具，因为它们在激活和/或启动植物对害虫的防御反应方面具有公认的作用。本工作通过行为实验（无选择和二选）和挥发性化合物分析来评价橄榄树外源施用肽系统素对橄榄蝇侵染的影响，并阐明其作用机制。主要植物防御。与未处理的树枝相比，用 10 nM 系统素处理橄榄枝可显着减少产卵（最多 3.0 倍）和受感染果实的数量（最多 2.9 倍），从而提供针对橄榄蝇的保护。这种保护作用甚至在邻近未处理的树枝中也被检测到，这表明系统素具有触发植物间通讯的能力。涂底漆的橄榄的威慑活性与挥发性物质2-乙基-1-己醇、乙酸4-叔丁基环己酯和1,2,3-三甲基苯的排放有关，这些物质与产卵和苍蝇侵扰呈负相关。系统素还被证明可以触发橄榄中特定挥发物（酯）的生物合成，以应对苍蝇的攻击。总体而言，观察到的系统素对橄榄蝇的保护可能是由于特定挥发物的释放，这些挥发物可以充当防御和/或信号分子以上调植物防御反应。因此，系统素代表了一种管理橄榄果蝇的新颖且有用的工具。