自然恢复延滞性是放牧退化草原管理的瓶颈之一，最新研究发现，长期过度放牧植物表型可塑性的克隆代间传递（即母体效应），在其中扮演关键角色。迄今，关于放牧植物母体效应维持与代际消减的机理，究竟是表观遗传的控制，还是芽库影响？抑或兼而有之？尚缺乏实验证据。为此，本项目依托国际最新进展和实验室前期基础，基于草原植物主要依靠克隆繁殖保持世代更新的特性，以克隆植物羊草（Leymus chinensis）为对象，通过典型草原长期过度放牧与围封羊草根茎芽的克隆培养与代际跟踪，研究长期过度放牧羊草母体效应及其克隆消减的代际过程，解析再次放牧刺激下两种来源羊草克隆后代的差异化反应规律及成因，进一步从表观遗传和芽库影响入手，阐明DNA甲基化在放牧羊草母体效应及代际消减中的作用，探究芽库变化对羊草克隆后代的关系，从而揭示放牧植物母体效应维持与代际消减的机理，为放牧草原生产力调控，提供一定的理论依据。

Legacy effect of grazing-induced degradation is a technical bottleneck in grassland management. Recently, some studies found the clonal transgenerational plasticity (i.e. maternal effect) of long-term grazing plants played important role in this legacy effect. However, there have little experimental evidences in the mechanisms underlying the maternal effect of long-term grazed plants and its restoration in clonal offspring, especially in the effects of epigenetics and bud bank. Here, in this project, we will conduct some experiments of clone culture and intergenerational tracking by bud culture in Leymus chinensis, which experienced long-term grazing and fencing in typical steppe of China. We will detect that (i) the processes of the maternal effect of long-term grazed plants and its restoration in clonal offspring of Leymus chinensis; (ii) the divergent responds of the clonal offspring of long-term grazed and fenced plants to grazing; (iii) the role of DNA methylation in the of the maternal effect and its restoration in clonal offspring, and (iv) the relationship of bud bank dynamics of Leymus chinensis with the grazing-induced maternal effect. The aim of this project is to pave foundation for regulation of grazed grassland productivity.