本地植物内生菌响应外来植物成功入侵进程及其对宿主生态效应与机制

Reinforcement of the prevention and control of alien species as well as maintenance of ecological security depend on the deeper analysis of alien plants invasion mechanisms. Existing studies have shown that endophytes could be a deeper mechanism of alien plants’ successful invasion. However, these studies focused only on the endophytes of alien plants , not on the endophytes of native plants (in particular, the responses of native plants’ endophytes to alien plants invasion on the host itself , and the relationship between the native plants’endophytes and alien plants invasion). Based on our previous research on the mechanism of Wedelia trilobata’ invasion, three kinds of invasive plants- Solidago canadensis, Alternanthera philoxeroides,Wedelia trilobata (which are known as the very serious invasive plants in China) and three kinds of native plants-Solidago decurrens, Alternanthera sessilis, Wedelia chinensis (which have the similar niche with three kinds of invasive plants at the invasion sites) were selected as the main research objects. By integration of ecology, molecular biology, bioinformatics, microbiology, plant science and other theories & methods as well as techniques, this research is to analyze the structure and function of different endophytes communities in different plants and the bio-ecological effects of important endophytes , to explore the relationship between “alien plant invasion - endophytic communities of native plant - native host plant”, to elucidate the responses of native plants endophytes to alien plants invasion and its ecological effects on its host plants as well as their effects on alien plants invasion. These research results might not only enrich the invasive mechanisms of alien plants, but also contribute to better understand the mechanisms among plant-plant, plant-microbial interaction. Furthermore, it can also provide a strong support for the prevention and control of alien invasive plants in practice.

加强外来生物防控、维护生态安全依赖于从更深层次解析外来植物入侵机理。已有的研究表明内生菌应是外来植物成功入侵又一深层次机制。但这些研究主要集中于入侵植物内生菌，缺少对本地植物内生菌(特别其响应外来植物入侵对宿主本身的效应及其与外来植物入侵关系)研究。基于我们前期对植物入侵机理的研究，以在我国暴发十分严重的三种入侵植物及入侵地对应相似生态位3种本地植物为主要对象，整合生态学、分子及生物信息学、微生物学、植物学等理论、方法与技术，解析本地植物内生菌群落在外来植物不同入侵进程的结构与功能、重要内生菌群生物生态效应，探讨“外来植物入侵-本地植物内生菌群落-本地宿主植物”相互关系，阐明本地植物内生菌响应外来植物入侵进程及对其宿主植物本身的生态效应及其对外来植物入侵的影响及机制。研究结果不仅可以丰富外来植物入侵机理，更深入理解植物与植物、植物与微生物互作机理；还可以在实践上为外来入侵植物防控提供支持。

加强外来生物防控、维护生态安全依赖于从更深层次解析外来植物入侵机理。已有的研究表明内生菌应是外来植物成功入侵又一深层次机制。但这些研究主要集中于入侵植物内生菌，缺少对本地植物内生菌(特别其响应外来植物入侵对宿主本身的效应及其与外来植物入侵关系)研究。本项目基于我们前期对植物入侵机理的研究，以在我国暴发十分严重的入侵植物南美蟛蜞菊、加拿大一枝黄花、空心莲子草等为主要对象，整合生态学、分子及生物信息学、微生物学、植物学等理论、方法与技术，解析本地植物内生菌群落在外来植物不同入侵进程的结构与功能、重要内生菌群生物生态效应；探讨“外来植物入侵-本地植物内生菌群落-本地宿主植物”相互关系。结果表明：不同营养、环境、胁迫条件下外来植物可以通过（兼性）内生菌、化感作用等改变土壤微生物、理化性质等，使其有利于自身营养吸收、竞争力提高、抗性水平增强。本研究还建立了内生菌分离与鉴定及其接种技术，验证了内生固氮菌、促生菌等内生菌的功能及其对宿主植物的生物生态效应；结果表明：内生固氮菌能够缓和氮受限条件下AMF和入侵植物间的营养竞争关系；内生促生菌在不同宿主植物体的表现有不同表现。在上述研究基础之上，本项目还提出了关于外来植物入侵研究的长期积累与思考，从新匹配整合了入侵生态学的时空理论体系。因此，本项目基本阐明了本地植物内生菌响应外来植物成功入侵进程及其对宿主生态效应与机制的核心目标任务，极大地丰富了植物入侵研究理论与入侵机制，同时深入理解植物与植物、植物与微生物互作机理；为外来植物防控提供了坚实的依据。