Elucidating the Chemical Ecology of Belowground Plant-Plant Communication

蚜虫，即绿蝇和黑蝇，是西欧和北欧的主要农业害虫。目前的控制措施包括使用可致人死亡的杀虫剂。需要其他可持续的方法来最大限度地减少杀虫剂的使用。一种方法是使用自然产生的有吸引力的化学物质，这些化学物质可以提高作物中有益昆虫的表现。然而，由于这些化学品的部署昂贵且难以维护，导致工厂释放这些引诱剂代表着更可持续的前景。我们已经证明，被豌豆蚜虫侵染的豆科植物增加了邻近豆科植物对攻击蚜虫的寄生黄蜂的吸引力，这是通过地下通讯介导的。我们的进一步研究表明，蚜虫在地上取食会导致地下同一植物释放化学物质。我们认为，释放的化学物质对观察到的地下通讯负有责任。该项目的目的是通过识别释放的化学物质并确定它们对邻近植物的影响来利用这一发现。我们将(I)确定与蚜虫取食相关的信号从根部转移到周围环境的条件(Ii)使用新开发的分离技术分离根产生和释放的化学信号(Iii)使用复杂的分析化学方法识别分离的信号(Iv)测量寄生蜂对暴露于已识别信号的植物的行为反应，以及(V)使用挥发性收集技术和寄生蜂触角的电子记录来识别从暴露于化学信号的受体豆类植物中收集的诱导挥发性有机化合物(VOC)。该项目将有助于了解地下植物之间的交流，并代表着一个令人兴奋的机会，提供一种全新的化学信号工具，可用于控制世界主要农作物的害虫。

Aphids, i.e. greenflies and blackflies, comprise the major agricultural pests in Western and Northern Europe. Control currently involves the use of insecticides that kill. Alternative sustainable approaches are required which minimise insecticide use. One way is to use naturally-occurring attractive chemicals that enhance the performance of beneficial insects in crops. However, as deployment of these chemicals is expensive and difficult to maintain, causing the plant to release these attractants represents a more sustainable prospect. We have shown that bean plants infested with pea aphids increase the attractiveness of neighbouring bean plants towards parasitic wasps that attack aphids, and that this is mediated by belowground communication. Our further studies show that aphid feeding aboveground causes release of chemicals by the same plant belowground. We propose that the released chemicals are responsible for the observed belowground communication. The aim of this project is to exploit this discovery, by identifying the released chemicals and determining their effect upon neighbouring plants. We will (i) determine the conditions under which aphid-feeding related signals are transferred from roots to their surrounding environment (ii) isolate the chemical signals produced and released by roots using newly developed isolation techniques (iii) identify isolated signals using sophisticated analytical chemistry approaches (iv) measure the behavioural response of parasitic wasps to plants exposed to the identified signals and (v) identify the induced volatile organic compounds (VOCs) collected from recipient bean plants exposed to the chemical signals, using volatile collection techniques, and electrical recordings from parasitic wasp antennae. This project will contribute towards an understanding of plant-plant communication belowground, and represents an exciting opportunity to provide an entirely new class of chemical signal tools that can be used to control insect pests on major world crops.