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目的研究我国自然地理分布范围内远志Polygala tenuifolia的分子谱系地理情况,揭示其地理分布格局的形成原因,推测该物种潜在的冰期避难所及冰期后的迁移扩散路线。方法使用叶绿体非编码片段(trn L内含子序列)对远志在我国自然地理分布区内的39个居群308个个体的遗传变异分布模式进行检测。结果共发现26个多态性位点,得到12种叶绿体单倍型。单倍型系统发育分析显示远志自然居群可划分为南、北2个地理组群:北方(包括中国东北、中部、西北地区)组群和南方组群,南北组群没有共享单倍型。居群遗传结构分析表明2个地理组群之间遗传分化较大(Gst=0.783,P<0.001),物种水平遗传多样性较高(Ht=0.755),北方组群不存在明显的谱系地理结构。结论第四纪冰期时远志在中国北方和南方地区存在多个避难所;冰期后或间冰期,北方地区发生了明显的居群扩张事件;南、北组群的分化可能是由于长期的地理隔离所致。
Objective To study the molecular phylogeography of Polygala tenuifolia in the geographical distribution of natural geography in our country and to reveal the formation reason of its geographical distribution pattern and to speculate the potential shelter of the ice age and migration and diffusion after the ice age. Methods The variation patterns of genetic variation among 308 individuals in 39 populations of Polygala tenuifolia in the geographical area of China were detected by using non-coding chloroplast fragment (trn L intron). Results A total of 26 polymorphic loci were found and 12 chloroplast haplotypes were obtained. Haplotype phylogenetic analysis showed that Polygalaceae natural populations could be divided into two geographical groups in south and north: north (including northeastern China, central and northwestern regions) and southern groups, and northern and southern groups did not share haplotypes. The analysis of genetic structure showed that there was a great genetic differentiation between the two geographical groups (Gst = 0.783, P <0.001), high genetic diversity (Ht = 0.755), and no significant phylogeographic structure . Conclusion During the Quaternary glacial period, Polygalaceae has many shelters in northern and southern China. After the glacial or interglacial periods, obvious population expansion occurred in the northern region. The differentiation of the southern and northern groups may be due to long-term geographical isolation Due.