生物多样性 ›› 2010, Vol. 18 ›› Issue (3): 233-240.DOI: 10.3724/SP.J.1003.2010.233

• 论文 • 上一篇    下一篇

光皮桦6个南方天然群体的遗传多样性

张俊红1, 黄华宏1, 童再康1*, 程龙军1, 梁跃龙2, 陈奕良3   

  1. 1 浙江林学院, 浙江临安 311300
    2 九连山国家森林公园, 江西龙南 341701
    3 浙江丽水庆元林场, 浙江庆元 323800
  • 收稿日期:2009-11-11 出版日期:2010-05-20 发布日期:2012-02-08
  • 通讯作者: 童再康

Genetic diversity in six natural populations of Betula luminifera from southern China

Junhong Zhang1, Huahong Huang1, Zaikang Tong1*, Longjun Cheng1, Yuelong Liang2, Yiliang Chen3   

  1. 1Zhejiang Forestry University, Lin’an, Zhejiang 311300

    2Jiulianshan National Forestry Park, Longnan, Jiangxi 341701

    3Qingyuan Forestry Farm of Lishui City in Zhejiang Province, Qingyuan, Zhejiang 323800
  • Received:2009-11-11 Online:2010-05-20 Published:2012-02-08
  • Contact: Zaikang Tong

摘要:

为揭示中国特有珍贵用材树种光皮桦(Betula luminifera)天然群体的遗传多样性和遗传结构, 采用AFLP分子标记, 分析了采自浙江、福建、江西、广西和贵州5个省区6个天然群体的120份样品。9对引物获得了355个位点, 其中多态性位点323个。分析结果表明光皮桦天然群体具有较高的遗传多样性, 多态位点百分率(PPL)达90.99%, 各群体的PPL和Nei’s基因多样性(hj)分别为93.20–98.60%和0.3143–0.3645; 总群体遗传多样性指数(Ht)为0.3616, 群体间遗传分化系数(Fst)为0.0650, 群体间总的基因流较高(Nm = 3.5962)。AMOVA分析表明群体间的遗传变异占总变异的11.49%, 浙江临安群体和贵州修文群体间的遗传距离最大(0.0665), 江西龙南群体和广西龙胜群体间的遗传距离最小(0.0173), 且遗传结构分析显示这两个群体的部分个体可能来自同一近祖。Mantel检测发现, 群体间的遗传距离与地理距离没有显著相关性(r = 0.423, P = 0.113), 而与两两群体所在地的均温差呈显著相关(r = 0.449,P = 0.017)。结合群体实地调查, 可以得出光皮桦天然群体的遗传多样性和遗传结构的形成不仅与其广域分布、自然杂交、种子特性以及生活史有关, 而且与群体被人为砍伐、生境片断化等因素有重要关系。基于上述结果我们提出了光皮桦天然种群的保护策略。

Abstract:

Betula luminifera, a precious timber species in southern mountain areas of China, can be found only in natural reserves because of over harvesting. We examined the genetic diversity and genetic structure of six natural populations of B. luminifera distributed in Zhejiang, Fujian, Jiangxi, Guangxi, and Guizhou using AFLP markers. A total of 323 polymorphic loci were amplified and 355 alleles were detected using nine pairs of primers. Percentage of polymorphism loci (PPL) ranged 93.20–98.60% and Nei’s gene diversity (hj) ranged 0.3143–0.3645, suggesting a high genetic diversity in natural populations of B. luminifera. At the species level, the total genetic diversity (Ht) was 0.3616. High gene flow (Nm = 3.5962) was detected among populations, and the genetic differentiation coefficient was 0.0650. AMOVA analysis showed that genetic variation among the populations accounted for 11.49% of the total. Genetic distance was the largest (0.0665) between Zhejiang (LA) and Guizhou (XW) populations and the smallest (0.0173) between Jiangxi (LN) and Guangxi (LS) populations, indicating that LN and LS populations may originate from the same ancestor. Mantel test revealed that genetic distance was not significantly related to geographical distance (r = 0.423,P = 0.113) but was significantly relative to average temperature difference of each location (r = 0.449, P = 0.017). In combination with on-site investigation, we conclude that the present status of genetic diversity and genetic structure of natural populations of B. luminifera was strongly affected by harvesting and habitat fragmentation. We propose some suggestions on its conservation.