烟草野生、地方与栽培品系虫害诱导抗性的比较研究

In the domestication process of wild plants, plants often lose their adaptabilities to the harsh conditions of the outside world, showing weak or even no induced resistance. Induced defenses in plants (especially herbivore-induced plant volatiles, HIPVs) have attracted intensive studies in plant-insect interaction ecology, and been applied in biological pest control practices. While most of the studies focus on biochemical elements of HIPVs and ecological functions in their attraction to natural enemies, little attention has been directed to variation in induced defenses across different plant strains, including wild relatives, domesticated land races, and commercially available modern plant cultivars—within the same geographic region. Laboratory and field experiments will be designed to explore the differences in herbivore-feeding induced defenses among three tobacco strains, and their effects on host choice behavior of the herbivore Spodoptera litura and its parasitoid Meteorus pulchricornis. The outcome of this project would not only advance our understanding in theory of the role plant induced defenses play in plant-herbivore-parasitoid interaction, but also provide promising avenues to explore induced plant resistance in biological pest control practices in agriculture.

植物在驯化的过程中往往往丧失了对外界严酷条件的适应性，虫害诱导抗性减弱，甚至消失。虫害诱导植物抗性（尤其植物挥发物）是近年来植物与昆虫互作关系研究的热点领域，并开始应用于害虫生物防治实践。但相关研究大多注重寄主植物生化物质成分的分析，对其生态学研究则集中于是否吸引植食性昆虫的天敌，鲜有关注同一发源地同种植物的野生、地方和栽培品系间虫害诱导植物抗性的差异，及其与植食性昆虫、天敌之间的深层次互作关系。本项目通过开展室内研究结合野外试验，探究同一发源地的不同烟草品系间虫害诱导抗性的差异、此诱导抗性如何影响斜纹夜蛾及其寄生蜂的选择偏好性。该研究在理论上将有助于阐释作物驯化及虫害诱导植物抗性在植物-害虫-天敌之间扮演何种“角色”，在实践中将为合理应用作物诱导抗性开展害虫生物防治实践提供参考。

植物在驯化的过程中往往丧失了对外界严酷条件的适应性，虫害诱导抗性减弱，甚至消失。虫害诱导植物抗性是近年来植物与昆虫互作关系研究的热点领域，并开始应用于害虫生物防治实践。但相关研究大多注重寄主植物生化物质成分的分析，对其生态学研究则集中于是否吸引植食性昆虫的天敌，鲜有关注同种植物的野生、地方和选育品种间虫害诱导植物抗性的差异，及其与植食性昆虫、天敌之间的深层次互作关系。本项目通过开展室内研究结合野外实验，探究不同烟草品种间虫害诱导抗性的差异、此诱导抗性如何影响斜纹夜蛾及其寄生蜂的选择偏好性和生活史特征。研究发现，烟草的组成抗性和虫害诱导抗性呈正相关，野生种烟草的组成抗性比地方和选育品种烟草高，其虫害诱导抗性也比地方和选育品种烟草高。不同品种烟草的组成抗性和诱导抗性对斜纹夜蛾的生活史和产卵选择行为有显著影响。斜纹夜蛾的存活率、发育历期、蛹重、蛹期、羽化率和成虫干重均受到烟草虫害诱导抗性的不利影响，这一不利影响的程度随着烟草品种的不同而不同，也就是随着烟草组成抗性的变化而变化。食物种类对斜纹夜蛾幼虫的营养含量有着重要的影响，通过自下而上的级联作用，烟草品质可以影响到斑痣悬茧蜂的适合度。野生种烟草相对选育和地方品种而言，对斑痣悬茧蜂的生活史产生了更为不利的影响。本研究在理论上阐释了作物驯化及虫害诱导植物抗性在植物-害虫-天敌之间扮演何种“角色”，在实践中将为合理应用作物诱导抗性开展害虫生物防治实践提供参考。