羊草叶色渐变群生活史特性和抗逆生理对遗传多样性响应的分子机制

A fine grass, Leymus chinens, is widely distributed with high economic value on natural grassland, China. Study object is germplasm source L. chinensis on natural grassland. Life history characteristics and stress resistance physiology of leaf color cline of L. chinensis and molecular mechanisms of response on genetic diversity were studied on habitats of different soil water and nutrient. Reproduction characteristics, population structure, population biomass and allocation will be analyzed. Genetic diversity of population will be compared. Comparative analysis of osmoregulation, antioxidant enzymes and physiological integration of population will be made. Response of life history characteristics on genetic diversity will be analyzed. Response of Stress physiology of leaf color cline of L. chinensis on genetic diversity will be analyzed. The relationships between the rule of genetic diversity and life history characteristics or stress physiology will be analyzed. The relationships between life history characteristics and stress physiology will be studied. Qualitative and quantitative analysis of divergence adaptation of leaf color cline of L. chinensis will be analyzed at molecular level. The study will reveal biological ecology principles and its evolutionary significance of divergence adaptation for leaf color cline L. chinensis at different genetic diversity gradients, contributing to deepen plant population ecology and evolutionary ecology theories and to enrich the study system of cline. And these theories and methods also will provide guidance for training and production of L. chinensis germplasm resources.

羊草是我国天然草原广泛分布、经济价值较高的优良禾本科牧草。以天然草原种质源羊草为研究对象，开展土壤水分和土壤养分等生境条件下，羊草叶色渐变群生活史特性和抗逆生理以及对遗传多样性响应的分子调节机制研究。研究内容包括羊草叶色渐变群的繁殖特征、种群结构、种群生产和分配的比较研究；种群遗传多样性的研究；种群的渗透调节、抗氧化酶和生理整合的比较分析；生活史特性对遗传多样性响应的研究；羊草叶色渐变群抗逆生理特征对遗传多样性的响应研究；生活史特性和生理特征的变化规律与遗传多样性变化规律的关系分析；羊草叶色渐变群生活史特征与生理特征的关系；羊草叶色渐变群趋异适应的分子水平定性和定量综合分析。揭示不同遗传多样性系列的羊草叶色渐变群趋异适应的分子调节机制的生物生态学原理及其进化意义，为植物种群生态学和进化生态学理论深化作贡献，丰富渐变群研究体系，其理论与方法也将为羊草种质资源培育等生产实践提供科学指导。

羊草是我国天然草原广泛分布、经济价值较高的优良禾本科牧草。本项目以不同叶色羊草为研究对象，通过异质生境原位试验，同质园实验和氮添加和盐碱条件等胁迫实验，对天然种群和实验种群的遗传多样性、生活史特性和抗逆生理特性进行了深入研究。遗传多样性实验结果表明灰绿色羊草和黄绿色羊草已产生显著分化，但过渡叶色羊草来源于灰绿色或黄绿色叶色羊草种群。同质园实验和氮添加和盐碱条件等胁迫实验结果表明不同叶色羊草具有生理响应和种群生活史特征的已产生分化，羊草叶色渐变群的遗传多样性与生活史和抗逆生理特性的部分指标具有显著相关性，不同叶色羊草的生理响应分化是由遗传特性决定的，但天然草原异质生境原位实验结果表明不同叶色羊草虽有在种群结构和有性生殖策略有显著差异，但其差异是由异质生境环境条件所引起的。本项目研究结果达到了项目的预期目标，揭示了羊草叶色渐变群分化的趋异适应机制，阐释了羊草叶色渐变群的遗传多样性与生活史和抗逆生理特性的变异规律及其生物生态学证据，深入分析了羊草叶色渐变群生理和种群分化对遗传多样性响应的生物生态学机制。