云贵地区金铁锁EST-SSR遗传多样性分析

EST-SSR analysis of genetic diversity of Psammosilene tunicoides in Yunnan-Guizhou provincial region

目的分析云贵地区金铁锁Psammosilene tunicoides遗传多样性和变异情况。方法采用转录组测序技术开发金铁锁的EST-SSR引物,并利用筛选出的分子标记对金铁锁进行多态性分析。结果共获得了17 530条含SSR位点的EST序列;筛选出了14对具有较高多态性的EST-SSR引物,对云贵地区的17份金铁锁进行多样性分析,发现其在位点水平上多态性信息含量(PIC)范围为0.350 0~0.795 0,具有较高的多态性;在群体水平上明显偏低,多态位点百分率(PPB)为64.29%~100%,Nei’s基因多样性指数的范围为0.188 2~0.477 7,平均0.323 2;云贵地区金铁锁群体内基因流(Nm)较小(Nm均值为0.302 0),群体间存在较大的遗传分化(Fst均值为0.452 9)。结论转录组测序丰富了金铁锁EST数据库;云贵地区金铁锁的遗传多样性可能与其繁殖方式、分布区较长的进化历史有关,群体间遗传分化大可能是地理阻隔截断了不同群体间的基因交流。

Objective To analyze the genetic diversity and variation of Psammosilene tunicoides in Yunnan-Guizhou provincial region. Methods The genetic diversity of different populations of P. tunicoides with high polymorphism was analyzed by using EST-SSR primers developed from transcriptomic sequencing technique. Results A total of 17 530 SSR-containing EST sequences were obtained by transcriptomic sequencing, 14 pairs of polymorphism EST-SSR primers were used to analyze the genetic diversity of 17 populations of P. tunicoides in Yunnan-Guizhou region, the results showed that the P. tunicoides in different populations had a high level of genetic diversity with the polymorphic information content（PIC） in the range from 0.350 0 to 0.795 0 in locus level; and had a lower value in group level with percentage of polymorphic bands（PPB） of 64.29%—100%. And the range of Nei＇s genetic similarity coefficient was from 0.188 2 to 0.477 7 with mean value of 0.323 2. The gene flow in P. tunicoides in Yunnan-Guizhou region was small with Nm mean value of 0.302 0, and there is a large genetic differentiation between groups with Fst mean value of 0.452 9. Conclusion Transcriptomic sequencing enriched P. tunicoides EST database. The genetic diversity of P. tunicoides might be related to the long evolutionary history of reproductive pattern and distribution area. And there was a highly genetic diversity among the populations of P. tunicoides in Yunnan-Guizhou region, it might be that the geographic barrier cut off the genes exchange among different populations.