(E)-β-farnesene (EBF) is an important chemical cue mediating interactions between plants, aphids, and natural enemies. This chemical has two origins, being secreted by aphid as an alarm pheromone and also produced by the attacked plants as a semiochemical attracting natural enemies. Despite the important role of this volatile chemical, little is known on the molecular mechanisms mediating the attraction of natural enemies to EBF. Here, we first verified that the larvae and adults of aphid predator hoverfly Eupeodes corollae detect and are attracted to EBF. Then, we found a neuron housed in type III basiconic sensilla of adult antenna responding to EBF. We further verified that in both adults and larvae odorant receptor EcorOR3 and odorant-binding protein EcorOBP15 mediate detection of EBF and structurally similar volatiles. Finally, we provide evidence that larvae of E. corollae may use aphid-derived EBF for prey location in the short-range, whereas adults could detect plant-derived EBF to find attacked plants from longer distances. Thus, while dissecting the molecular basis for attraction to EBF produced by two different sources, our results may find potential applications in integrated aphid management approaches.

( E )-β-法呢烯 (EBF) 是一种重要的化学信号，介导植物、蚜虫和天敌之间的相互作用。这种化学物质有两个来源，由蚜虫分泌作为警报信息素，也由被攻击植物产生作为吸引天敌的化学信息素。尽管这种挥发性化学物质具有重要作用，但对于介导天敌对 EBF 的吸引力的分子机制知之甚少。在这里，我们首先验证了蚜虫捕食者hoverfly Eupeodes corollae的幼虫和成虫检测并被EBF 吸引。然后，我们发现一个神经元位于成人天线的 III 型基本感受器中，对 EBF 有反应。我们进一步证实，在成虫和幼虫气味受体EcorOR3和气味结合蛋白中EcoOBP15介导 EBF 和结构相似的挥发物的检测。最后，我们提供证据表明E. corollae的幼虫可能使用蚜虫衍生的 EBF 在短距离内定位猎物，而成虫可以检测植物衍生的 EBF 以从更远的距离寻找受攻击的植物。因此，在剖析两种不同来源产生的 EBF 吸引的分子基础时，我们的结果可能会在综合蚜虫管理方法中找到潜在的应用。