薇甘菊种群在海南扩散过程中性状的进化研究

入侵种在扩散过程中常常发生着性状的快速进化，然而，当前人们对这一问题在入侵植物中的研究还较少，且研究的性状一般是种子大小和传播能力、竞争能力，而忽视了对影响种子传播能力进化的机制、竞争能力的进化在种群水平上的生态学效应、表型可塑性、自交能力和种子发芽性状的研究。为此，本项目提出以下科学问题：入侵植物扩散过程中其种子大小和传播能力如何进化，局部种群密度在其中的作用是什么？种内种间竞争能力如何进化，种内竞争能力的降低是否可提高群体水平上的入侵能力？表型可塑性、自交的可能性、种子发芽率和发芽速度如何进化？本项目拟以在海南快速扩散的入侵植物薇甘菊为材料，采用同质园实验，通过研究不同扩散距离的种群在性状方面的差异及其机制或生态学效应，来回答上述问题。本项目在理论上可发展植物入侵的扩散理论，扩展和深化人们对入侵植物扩散过程中性状进化模式及其机制或效应的认识，实践上可为入侵植物的防控管理提供科学依据。

The traits of invasive species often rapidly evolve during spread, but currently human research on this topic is limited in invasive plants, and the traits studied are commonly seed size and dispersal ability, and competitive ability, ignoring the research on the mechanisms influencing the evolution of seed dispersal ability, the population-level ecological effect of the evolution of competitive ability, phenotypic plasticity, the capacity for self-fertilizaiton, and seed germination traits. Thus, this project raises the following scientific questions: how do the seed size and dispersal ability evolve during spread in invasive plants, and what is the role of local population density in this evolution? How do the intra- and interspecific competitive ability evolve, and can the reduced intraspecific competitive ability increase the population-level invasiveness? How do phenotypic plasticity, the capacity for self-fertilizaiton, seed germination rate and germination speed evolve? Using the rapidly spreading invasive plant Mikania micrantha in Hainan as the target plant and through common garden experiments, this project aims to answer the above questions by studying the trait differences among populations with different spreading distances and their mechanisms or ecological effect. Theoretically, this project can develop the theory of spread in plant invasion and broaden and deepen human understanding of the patterns of trait evolution during spread of invasive plants, and their mechanisms or ecological effect, and practically, this project can provide a scientific basis for the prevention, control and management of invasive plants.