Fruit host selection by the olfactory system in the agricultural pest Drosophila suzukii

该项目研究了新兴农业害虫铃木果蝇的嗅觉系统如何编码宿主的气味，旨在识别有吸引力的配体和它们的混合物，这些配体和混合物可以用作陷阱中的诱饵。铃木氏杆菌是东亚的一种地方病，2008年首次在西班牙被发现，此后向欧洲北部入侵，于2012年9月到达英国。铃木夜蛾是一种极端的多面手捕食者：这种苍蝇在草莓、葡萄和蓝莓等多种植物科的果实中产卵。多面手昆虫如何选择寄主是昆虫与植物关系中的一个核心问题。通过单个感觉神经元的电生理学分辨率，我们将测试嗅觉系统如何编码来自水果宿主的气味的假设。在不同寄主发出的花束中是否存在共享的关键配体，从而激活嗅觉系统中介导行为吸引的感觉神经元的共同亚群，还是不同寄主发出的花束激活了相互排斥的感觉神经元群？我们对模式生物黑腹果蝇嗅觉系统的了解将为我们对铃木氏线虫的研究提供信息。测量对纯单一气味和多成分混合物的行为吸引力的分析将提供嗅觉信息处理的定量读数，并且将输出与输入联系起来的数学模型将深入了解混合识别的重要性。在实验室中具有吸引力的混合物是监测和控制果园中铃木氏夜蛾种群的有价值的陷阱候选诱饵。这个跨学科项目将提供昆虫行为、分析化学和触角电生理学方面的培训。在洛桑研究所的轮转中，学生将获得使用Pettersson四臂嗅觉仪进行昆虫行为实验的技能，重点是对气味剂量的吸引反应的量化发展，并将接受生物化学方法的培训，包括从田间植物和水果中捕获挥发性物质，并使用高分辨率气相色谱(GC) /耦合GC- ms进行分析。学生将参加以化学生态学为重点的实验室会议，这是洛桑研究所的一个特殊专业领域。随后在卡迪夫的轮换将向学生介绍果蝇的生理学，学生将学习昆虫感觉神经元的细胞外记录技术。在卡迪夫，学生将与由四个密切合作的果蝇群体组成的研究环境进行互动。导师：Wynand Van der Goes Van Naters博士，Mike Birkett博士（Harpenden, Rothamsted Research）

This project investigates how the olfactory system of the emerging agricultural pest Drosophila suzukii encodes host odours, and aims to identify attractive ligands and their mixtures that can be used as baits in traps. Endemic to eastern Asia, D. suzukii was first recorded in Spain in 2008 and has since invaded northwards in Europe, reaching the UK in September 2012. D. suzukii is an extreme generalist feeder: the fly lays its eggs in fruit from diverse plant families including strawberry, grape and blueberry. How a generalist insect selects its hosts is a central question in insect-plant relationships. By electrophysiology at the resolution of single sensory neurons, we will test hypotheses of how the olfactory system encodes odours from fruit hosts. Are there shared key ligands in the bouquets emitted by the different hosts, which thereby activate common subpopulations of sensory neurons in the olfactory system that mediate behavioural attraction, or do different host bouquets activate mutually exclusive groups of sensory neurons? Our knowledge of the olfactory system of the model organism Drosophila melanogaster will inform our research on D. suzukii. Assays measuring behavioural attraction to pure single odorants and to multicomponent blends will provide quantitative readouts of processing of olfactory information, and a mathematical model which relates output to input will give insight into the importance of blend recognition. Blends that are attractive in the laboratory are valuable candidate baits for traps to monitor and control D. suzukii populations in orchards. This interdisciplinary project will provide training in aspects of insect behaviour, analytical chemistry and antennal electrophysiology. In the rotation at Rothamsted, the student will acquire skills in behavioural experiments with insects using a Pettersson four-arm olfactometer, focussing on the development of quantification of attractive response to odour dose, and will be trained in biological chemistry methods, including volatile capture from plants and fruits in the field and analysis using high resolution gas chromatography (GC) / coupled GC-MS. The student will participate in lab meetings focussed on Chemical Ecology, which is an area of particular expertise in Rothamsted. The subsequent rotation in Cardiff will introduce the student to the physiology of Drosophila, and the student will learn techniques for extracellular recordings from insect sensory neurons. In Cardiff, the student will interact with a research environment formed by four Drosophila groups, which co-operate closely. Supervisors: Dr Wynand Van der Goes van Naters, Dr Mike Birkett (Harpenden, Rothamsted Research)