七里峪不同海拔茶条槭种群的遗传多样性

Genetic Diversity of Acer ginnala Populations at Different Elevation in Qiliyu Based on ISSR Markers

利用ISSR分子标记研究七里峪1200～2000m8个海拔梯度茶条槭种群的遗传多样性和遗传结构。11条引物共得到78个重复性好的位点,在物种水平上,多态位点78个,多态百分率为100%。在8个茶条槭种群中,总遗传多样性指数I(Shannon多样性指数)、HB(Bayesian指数)分别为0.507和0.368,表现出高的遗传多样性。8个种群的遗传多样性呈现出随海拔升高而增大的趋势。AMOVA分析表明,74.3%的遗传变异存在于茶条槭种群内,25.7%存在于种群间(ΦST=0.257,P<0.001)。相关回归分析显示,茶条槭种群的遗传多样性指数与土壤含水量、土壤全氮含量表现出显著的相关关系。8个种群可大致分成2组,与其地理分布相一致。茶条槭本身的生物学特性与不同海拔种群所处生境的异质性是七里峪茶条槭种群现有遗传格局的主要原因。

To estimate genetic diversity and genetic structure of Acer ginnala at different elevations,eight natural populations in Qiliyu from 1 200 m to 2 000 m were surveyed using ISSR markers. At species level,a total of 78 reproducible DNA loci were yielded by 11 primers,and all of them were polymorphic,accounting for the percentage of polymorphic loci being 100% . Among the populations investigated,the total gene diversity I,HB equaled 0. 507 and 0. 368 respectively,indicating a high genetic diversity occurred within A. ginnala. The amount of genetic variation of eight populations exhibited an increase along the elevation gradient. AMOVA showed that 25. 7% of the total genetic variation existed among populations and 74. 3% within populations（ΦST = 0. 257,P 0. 001） . Regression analysis revealed significant relationships happened between the genetic diversity index and soil moisture content,soil total nitrogen respectively. The eight populations of A. ginnala were clustered into two groups based on PCoA and STRUCTURE analysis,which was consistent with their geographic distribution. The genetic variation pattern of A. ginnala in Qiliyu might be ascribed to heterogeneous habitats and biological characteristic of this species.