中文摘要：

采用L16（45）正交设计,对鹅掌楸属SRAP-PCR反应的5个因素（Mg2＋、dNTPs、引物、Taq酶和模板DNA浓度）在4个水平上进行优化试验,同时对SRAP反应影响较大的Mg^2＋、Taq酶、模板DNA浓度进行单因素分析。建立鹅掌楸属植物SRAP-PCR最适反应体系（20μL）,反应条件为：Mg2＋3.0 mmol·L^-1,dNTPs0.3 mmol·L^-1,引物浓度0.9μmol·L^-1,Taq酶2.0μmol·min-1,模板DNA 90 ng,10×PCR buffer 2μL,不足部分以ddH2O补足。利用优化的SRAP体系对鹅掌楸属10个不同地理种源进行遗传多样性分析。筛选出15对条带清晰、多态性高的引物共扩增出182个位点,其中149个为多态性位点,多态性比例为81.87%。应用POPGEN 32软件通过UPGMA法进行聚类分析,从聚类图可以看出10个地理种源间的遗传距离及亲缘关系,表明SRAP分子标记可以运用于鹅掌楸属的遗传多样性研究。

英文摘要：

The SRAP-PCR reaction system of Liriodendron was optimized with an orthogonal design to choose the most proper concentrations of Mg2＋ , dNTPs, primers, Taq polymerase and template DNA at four levels. The concentrations of Mg2＋ , Taq polymerase, template DNA were further fine-adjusted with a single-factor design. The optimized SRAP-PCR system （total 20 μL）was as follows： Mg2＋ 3.0 mmol. L-1, dNTPs 0.3 mmol·L-1, primer 0.9μmol·L-1, Taq polymerase 2.0 μmol- min-1 and DNA template 90 ng, 2 μL 10 PCR buffer and ddH20. With the system, genetic diversity of 10 provenances of Liriodendron was analyzed. The results showed that, 182 loci were generated from the 15 screened primer pairs, of which 149 loci were polymorphic. The percent of polymorphic loci was 81.87%. The dendrogram of Liriodendron was constructed based on cluster analysis （UPGMA） with the Package of POPGEN 32. The genetic distance and relative relationship of the 10 provenances of Liriodendron was shown by the dendrogram distinctly. It indicated that SRAP molecular marker could be widely used in genetic diversity analysis of Liriodendron.