不同地理种源中国特有濒危珍贵树种桢楠的遗传多样性研究

Phoebe zhennan S. Lee et FN Wei is an endangered second-class protected plants endemic to China. This research will concentrate on the relationship between the environmental factors and the genetic diversity, the environmental factors and the genetic variation of different geographical provenance apparent of P.zhennan. .In this study, SRAP and ISSR molecular markers will be used to analyze the genetic diversity of the different sources P.zhennan, and the association between environmental factors and habitat of different provenances P.zhennan will be studied. .The genetic variation and genetic rules within populations and among populations will be analyzed; To investigate the influence of environmental factors on distribution P.zhennan,the correlation analysis of the distribution of populations and environmental factors in different geographical provenance P.zhennan will be researched. The variation and change between the amplitude and environment factor of the different P.zhennan source will be studied. And the environment suitable to the growth and distribution of the P.zhennan will also be analyzed..Through the research, it would be favor to lay the theoretical and practical basis for the excavating, recovery nurturing and qualitifing development of new varieties germplasm resources of the P.zhennan.

桢楠（Phoebe zhennan S. Lee et F. N. Wei）是我国特有的濒危Ⅱ级保护植物，本研究主要围绕不同桢楠地理种源的环境因子和遗传多样性、表观遗传变异展开研究。本研究利用SRAP和ISSR分子标记技术对不同种源地的桢楠遗传多样性进行分析，并与原栖息地环境因子进行关联性分析,研究不同种源地桢楠居群的遗传规律和遗传变异；通过对我国不同地理种源桢楠居群分布与环境因子的相关性分析，研究桢楠不同种源地环境因子变化规律和变化幅度，探讨环境因子对桢楠分布的影响，掌握桢楠生长分布的适宜环境，为桢楠的种质资源发掘、恢复性培育以及优质新品种的培育奠定理论和实践基础。

桢楠是我国特有的濒危Ⅱ级保护植物，针对桢楠进行遗传多样性和表观遗传变异方法的建立和分析尤为重要。本研究首先对桢楠适生性进行预测，分析了桢楠的适宜分布区，影响其分布的气候因子，以及气候变化对桢楠分布的影响。结合ITS分子标记进行亲缘关系预测，并在二代测序的基础上对简单重复序列（SSR）分子标记进行开发和MSAP甲基化多态性标记方法的建立。研究表明，桢楠最佳适生区主要为川渝交界、渝贵交界、渝鄂交界、鄂湘交界，以及贵州中西部等部分地区。ITS序列分析表明，不同种源桢楠明显分为两支，具有明显的种间差异性。将楠木高通量转录组测序获得的67331条Unigene进行SSR位点挖掘和分析，并对引物验证，初步证明其可行性，得到22对引物用于后续的分析。同时建立了桢楠DNA甲基化水平的表观遗传差异分析方法。桢楠是特色濒危树种，对其适生条件、遗传多样性以及濒危机制的研究具有重要的理论和现实意义。