表观遗传变异在不同纬度芦苇响应局域环境变化中的作用

植物对环境变化的表型响应不仅受遗传变异的调控，同时与表观遗传变异密切相关。表观遗传变异如DNA甲基化修饰可提高子代对环境变化的敏感性，促进植物的性状进化。目前关于植物表观遗传变异的稳定性和生态作用机理尚不明确。克隆植物不具减数分裂过程，表观遗传信息在代际间的有效传递可能在其响应局域环境变化中起着重要作用。本项目以典型湿地克隆植物芦苇(Phragmites australis L.)为研究对象，选择我国不同纬度梯度的河口湿地为研究区域，运用分子标记和实验生态学等研究方法，研究不同纬度芦苇自然种群的遗传变异、表观遗传变异与表型变异间的关系，探究不同纬度植株表观遗传变异的遗传稳定性及进化潜势，揭示母代DNA甲基化在子代响应局域环境变化中的作用机制。以此阐明表观遗传变异在湿地克隆植物响应局域环境变化过程中的作用机制，进一步完善克隆植物进化生态学理论，并为气候变化下湿地植被恢复提供一定的理论依据。

Phenotypic responses of plants to environmental change are not only regulated by genetic variation, but also closely related to their epigenetic variation. The epigenetic variation induced by environment, such as DNA methylation, can be passed on to the offspring to improve their sensitivity to environmental change, and to promote the evolution of plant traits. However, the stability and ecological function of epigenetic variation of plants are still not clear. As clonal plants without meiosis process, the effective inter-generational transmission of epigenetic information may play an important role in responses of clonal plants to local environmental change. In this project, the typical wetland clonal plant Phragmites australis L. from estuarine wetlands at different latitudes will be selected, and techniques of molecular marker and experimental ecology will be used to study the relationship among genetic variation, epigenetic variation and phenotypic variation of P. australis from natural populations at different latitudes, to explore genetic stability and evolutionary potential of epigenetic variation of different plant genotypes, and to reveal the roles and related mechanism of maternal DNA methylation in phenotypic responses of the offspring. On this basis, the function and potential mechanism of epigenetic variation in responses of wetland clonal plants to environmental change will be clarified, and the theory of evolutionary clonal plant ecology will be further improved. Meanwhile, the results can also provide a theoretical basis for dynamic prediction and restoration of wetland vegetation under global climate change.