内蒙古中西部草原区五种针茅的遗传多样性研究

Study on Genetic Diversity among 5 Species of Stipa L. of Steppe in Middle and Western Inner Mongolia

利用RAPD(Random Amplified Polymorphism DNA,RAPD)分子标记技术,对内蒙古中西部草原区16个不同地理种群的五种针茅的遗传多样性及其种间关系进行了研究。从102个10碱基随机引物中筛选出28个有效引物,共扩增出389条带,多态性条带345条,占88.69%,说明针茅属植物具有丰富的遗传多样性,对环境的适应能力较强,PCA分析表明水热成为其地理分布的决定性因素。依据五种针茅的Jaccard相似系数所做的UPGMA聚类分析表明,大针茅和克氏针茅之间的遗传距离比较小聚为一类,它们与本氏针茅、短花针茅和小针茅间的遗传距离都比较大。

The genetic diversity and relationships among 5 species of Stipa L. was studied by use of RAPD molecular marker method with samples collected from 16 different geographic populations in the steppe of middle and western Inner Mongolia. The 28 10-bp primers were screened from 102 arbitrary primers, and a total of 345 bands were detected out of 389 bands, accounting for 88.69 %. The result showed that the Sti- pa L. had a high level genetic diversity, demonstrating strong adaptability to the environment, and temper- ature and precipitation played an important role on their spatial distribution. The UPGMA cluster with Jaccard similarity coefficients showed that S. grandis and S. krylovii had a close relationship, and far from others, i.e.S, breviflora, S. bungeana and S. klernenzii, in terms of genetic distance.