植物生态学报 ›› 2009, Vol. 33 ›› Issue (1): 1-11.DOI: 10.3773/j.issn.1005-264x.2009.01.001

所属专题: 青藏高原植物生态学:种群生态学

• 研究论文 •    下一篇

江孜沙棘和云南沙棘之间谱系分化和亲缘地理

程凯1,2, 孙坤3, 温红艳4, 张敏1, 贾东瑞2, 刘建全2,*()   

  1. 1 四川农业大学农学院,四川雅安 625014
    2 兰州大学生命科学院干旱与草地教育部重点实验室,兰州 730000
    3 西北师范大学生命科学学院,兰州 730070
    4 云南省丽江市生物资源开发创新办公室,云南丽江 674100
  • 收稿日期:2007-12-06 接受日期:2008-03-04 出版日期:2009-12-06 发布日期:2009-01-30
  • 通讯作者: 刘建全
  • 作者简介:*E-mail: liujq@nwbip.ac.cn
  • 基金资助:
    国家自然科学基金(30430560);教育部专项基金(NCET-05-0886)

MATERNAL DIVERGENCE AND PHYLOGEOGRAPHICAL RELATIONSHIPS BETWEEN HIPPOPHAE GYANTSENSIS AND H. RHAMNOIDES SUBSP. YUNNANENSIS

CHENG Kai1,2, SUN Kun3, WEN Hong-Yan4, ZHANG Min1, JIA Dong-Rui2, LIU Jian-Quan2,*()   

  1. 1College of Agriculture, Sichuan Agricultural University, Ya’an, Sichuan 625014, China
    2MOE Key Laboratory of Arid and Grassland Ecology, School of Life College, Lanzhou University, Lanzhou 730000, China
    3College of Life Sciences, Northwest Normal University, Lanzhou 730070, China
    4Management Office of Utilization and Innovation of Biological Resources, Lijiang, Yunnan 674100, China
  • Received:2007-12-06 Accepted:2008-03-04 Online:2009-12-06 Published:2009-01-30
  • Contact: LIU Jian-Quan

摘要:

研究具有邻近分布的近缘类群的遗传分化和谱系筛选对于进一步揭示物种形成机制具有重要意义。该文以沙棘属(Hippophae)临域分布的两个类群, 江孜沙棘(H. gyantsensis)和云南沙棘(H. rhamnoides subsp. yunnanensis)为研究对象, 进行群体水平上的母系分化研究。前一个种分布于西藏的中西部, 而后者主要分布于青藏高原东南部的云南西北部、四川西部和西藏东南部。两个类群在叶和果实性状存在明显区别。叶绿体在沙棘属植物中为母系遗传。共研究了两个类群14种群109个沙棘个体的叶绿体trnL-F、trnS-G序列; 序列排序后共发现11种单倍型, 江孜沙棘和云南沙棘分别有7种和6种, 两种单倍型为两个类群共享。分支分析和嵌套进化分析进一步表明, 两个类群之间的单倍型相互交错, 单倍型分化与形态上划分的两个类群不一致, 表明它们之间具有十分复杂的谱系筛选过程。这些发现明显不支持以前提出的有关江孜沙棘系统位置的假设。但是, 目前所获得的证据不能区分该物种究竟是通过异域分化还是同倍性杂交起源的。不同种群固定特有单倍型表明, 两个类群都在最后一次冰期可能存在多个避难所。

关键词: 云南沙棘, 江孜沙棘, 叶绿体DNA trnL-F, DNA trnS-G序列, 谱系筛选, 物种形成, 避难所

Abstract:

Aims In order to understand complex speciation, it is critically important to investigate the corresponding genetic divergence and lineage sorting between close species or taxa distributed in parapatric regions. Our aim was to outline the distribution of the maternally inherited chloroplast haplotypes of Hippophae gyantsensis and H. rhamnoides subsp. yunnanensis and construct their phylogeographic relationships. The former species occurs in central and west Tibet, while the latter is distributed in northwest Yunnan and west Sichuan. These taxa are distinguished by leaf shape, trichomes and fruits.
Methods We sequenced trnL-F and trnS-G DNA fragments for 109 trees of 14 populations from these two taxa.
Important findings A total of 11 chlorotypes were identified, seven in H. gyantsensis and six in H. rhamnoides subsp. yunnanensis, with two shared. Phylogenetic and Nested Clade Analysis analyses further suggested that the divergence of these haplotypes is highly inconsistent with morphological differentiation of the two taxa, suggesting complex maternal lineage sorting between them. These findings refute the previous systematic placements of H. gyantsensis within the genus. However, the available data could not distinguish between two alterative hypotheses regarding origin of this species: homoploid hybrid versus allopatric speciation. In addition, the unique haplotypes recovered in separate populations within each of two taxa suggest that multiple refugia might have maintained both across their distributional ranges during the Last Glacial Maximum.

Key words: Hippophae rhamnoides subsp. yunnanensis, H. gyantsensis, cpDNA, trnL-F, trnS-G, lineage sorting, speciation, glacial refugia