白沙蒿不同地理种群遗传分化的ISSR分析

运用ISSR技术，对白沙蒿的5个种群进行遗传分化的分析。12个引物在108个个体中共扩增出222个位点，其中，多态位点为218个，多态位点百分率为98.20%，Shannon多样性指数为0.315 4，具有高的多态性。种群间的遗传分化系数（G_st）为0.076 7，与AMOVA分析的结果一致（Ф_st为7.96%），表明绝大多数的遗传变异存在于种群内部。各种群间遗传一致度高达98%以上，遗传距离很小，基因流达3.008 2，均表现出白沙蒿各种群存在着广泛的基因交流，有着很小的遗传分化。

Genetic Differentiation of the Different Geographical Populations of Artemisia sphaerocephala by Inter-Simple Sequence Repeat (ISSR)

Inter-simple sequence repeat (ISSR) markers were applied to investigate the genetic diversity and differentiation of five geographical populations of Artemisia sphaerocephala. Using 12 ISSR primers, 222 loci were observed in 108 individual, of which 218 were polymorphic. A high level of genetic diversity was revealed: PPB=98.20% and Shannon’s index I=0.315 4 at the species level. Based on Nei’s G_st value （0.076 7）and analysis of molecular variance (AMOVA ，Ф_st=7.96%), it showed that the most genetic variation existed within the populations. Furthermore, it revealed there were wide gene flows and little genetic differentiation among populations of A.sphaerocephala due to high genetic identity(>98%), small genetic distance and the high gene flows(Nm=3.008 2).