秦巴山区漆树的遗传多样性分析

Analysis on Genetic Diversity of Toxicodendron vernicifluum in Mts. Qinling-Bashan Area

本研究应用9对SSR(simple sequence repeats)引物对11个漆树(Toxicodendron vernicifluum(Stokes) F.A.Barkley)自然种群共110个个体进行群体遗传分析,以期揭示秦巴山区漆树的遗传结构。结果表明,9对引物共检测出84个多态性条带,平均每个位点复等位基因9.333 3个(N=9.333 3);秦巴山区的漆树具有丰富的遗传多样性(物种水平:A=9.333 3,H=0.816 6,I=1.959 5;种群水平:A=1.989 9,H=0.421 3,I=0.607 2);分子方差分析(analysis of molecular variance, AMOVA)结果显示,漆树种群遗传分化强烈(F=0.481 9);聚类分析表明,地理距离较近的种群先聚为一类;Mantel Test统计表明秦巴山区漆树遗传距离与地理距离存在显著正相关(R=0.295,P≤0.01)。秦巴山区的漆树分布范围广且种群多,因此积累了丰富的遗传变异;推测漆树的虫媒传粉及种群的地理隔离是造成种群显著遗传分化的原因。基于丰富的遗传多样性和显著的种群遗传分化,我们建议秦巴山区漆树的保护以就地保护为主。

In this study, 9 pairs of SSR primers were used to analyze the population genetic structure of 110 individuals from 11 natural populations of Toxicodendron vernicifluum in Mts.Qinling-Bashan area. A total of 84 polymorphic bands were detected by 9 pairs of primers, with an average of 9.333 3 multiple alleles per locus(N=9.333 3). The genetic diversity of T.vernicifluum in Mts.Qinling-Bashan area was high(species level: A=9.333 3, H=0.816 6, I=1.959 5. Population level: A=1.989 9, H=0.421 3, I=0.607 2). Analysis of molecular variance(AMOVA) showed significant genetic differentiation(F=0.481 9). Cluster analysis showed that geographically closed populations tended to cluster together precedence. Mantel Test showed that there was a significant positive correlation between genetic distance and geographical distance(R=0.295, P≤0.01). The abundant genetic variation T. vernicifluum may be resulted from its wide distribution area and multiple populations. It is speculated that entomophilous pollination and geographical isolated population were the reasons for its remarkable genetic differentiation. Based on the rich genetic diversity and significant population genetic differentiation, we suggested that in situ conservation should be the priority for T. vernicifluum in Mts. Qinling-Bashan area.