Biodiversity Science ›› 2003, Vol. 11 ›› Issue (2): 109-117.doi: 10.17520/biods.2003015

• 论文 • Previous Article     Next Article

Conservation genetics of the endemic species Myricaria laxiflora (Tamaricaceae) in the Three Gorges Reservoir area, Hubei

LI Zuo-Zhou1, WANG Chuan-Hua1, 2, XU Tian-Quan1, WU Jin-Qing1, HUANG Hong-Wen1*   

  1. 1 Wuhan Botanical Garden,Wuhan Institute of Botany,Chinese Academy of Sciences,Wuhan 430074
    2 Caihua Township Government,Wufeng Tujiazu Autonomous County,Hubei Province,443408
  • Received:2002-08-20 Revised:2002-12-26 Online:2003-03-20
  • HUANG Hong-Wen

Allozymic variation of 13 natural populations and one ex situ population of Myricaria laxiflora were analyzed using isoelectric focusing in thin-layer polyacrylamide slab gels. Thirteen loci of five enzyme systems were examined and used for the analysis of population genetic diversity and structure. A high genetic diversity was observed in this species, with mean number of alleles per locus ofA=1.8, mean percentage of polymorphic lociP=78.7% and average expected heterozygosityHe=0.317, which were higher than the average value of Chinese endemic plant species. An excess of heterozygous genotypes was found both in natural and ex situ populations, suggesting a slight deviation from the Hardy-Weinberg equilibrium in the populations. The total genetic diversity (Ht) is 0.3733 within the species, while the genetic diversity within and among populations (Hs vs Dst) were 0.3168 and 0.0565, respectively, indicating that 84.86% of the genetic variation occured within populations and only 15.14% among natural populations. The mean gene flow among populations (Nm) was 1.401 and genetic distances among populations ranges from 0.002 to 0.176. Cluster analysis using UPGMA on Rogers' genetic distance revealed that populations of M. laxiflora growing along riversides in the Three-Gorges Reservior area were separated into upstream and downstream groups at Baishui River, Xietan region in Hubei Province. A level of genetic diversity similar to that of natural populations was observed in the ex situ population at Wuhan Botanical Garden, so the ex situ conservation program was considered to be successful in preserving genetic diversity. Combining analysis of the genetic diversity with available information on breeding system, status of natural habitat, and evolutionary history, the causes for the endangerment of M. laxiflora are discussed. It is likely that the species gradually evolved as a relict species after the Quaternary Glaciation. Based on evaluation of the current ex situ conservation program, we suggest that similar habitats upstream and downstream of the Three-Gorges Reservoir or on nearby tributaries should be selected as ex situ conservation spots for M. laxiflora populations with high genetic diversity before their original habitats are submerged by the Three-Gorges Reservoir.

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[1] Wang-Zhen Guo, Guo-Jia Ma, Yi-Chao Zhu, Chen-Xin Yi and Tian-Zhen Zhang. Molecular Tagging and Mapping of Quantitative Trait Loci for Lint Percentage and Morphological Marker Genes in Upland Cotton[J]. J Integr Plant Biol, 2006, 48(3): .
[2] PAN Yu-De, Melillo J. M., Kicklighter D. W., XIAO Xiang-Ming, McGuire A. D.. Modeling Structural and Functional Responses of Terrestria Ecosystems in China to Changes in Climate and Atmospheric CO2[J]. Chin J Plan Ecolo, 2001, 25(2): 175 -189 .
[3] Dai Yun-ling and Xu Chun-hui. Advances in Research on Protein Components of Oxygen-evolving Complex[J]. Chin Bull Bot, 1992, 9(03): 1 -16 .
[4] Wang Qingsuo, Dong Xuejun, Chen Xudong, Yang Baozhen. Study on Some Features of Artemisia ordosica Community at The Different Successional Stages[J]. Chin J Plan Ecolo, 1997, 21(6): 531 -538 .
[5] . [J]. Chin J Plan Ecolo, 1964, (2): 180 -189 .
[6] Deli Peng, Zhiqiang Zhang, Yang Niu, Yang Yang, Bo Song, Hang Sun, Zhimin Li. Advances in the studies of reproductive strategies of alpine plants[J]. Biodiv Sci, 2012, 20(3): 286 -299 .
[7] ZHANG Xiao-Quan, Xu De-Ying. A Canopy Radiation Model for Even-aged Plantation II Application and Validation[J]. Chin J Plan Ecolo, 2002, 26(1): 83 -88 .
[8] Dong-Mei Deng, Jin-Chuan Deng, Jun Zhang, Min Hu, Zhou Lin and Bin Liao. Accumulation of Zinc, Cadmium and Lead in Four Populations of Sedum alfredii Hance Growing on Lead/Zinc Mine Spoils: Field Investigation[J]. J Integr Plant Biol, 2008, 50(6): 691 -698 .
[9] Su Zhi-xian, Huang Yan-ping, Mu De-jun, Xiong Qun-xian, Zhong Zhang-cheng. Studies on the Features of Energy Value and the Factors of Affecting Measuring Energy Value of Neosinocalamus affinis Clone Population[J]. Chin J Plan Ecolo, 1993, 17(3): 273 -279 .
[10] Živa Fišer Pečnikar, Nataša Fujs, Robert Brus, Dalibor Ballian, Elena Buzan. Insights into the plastid diversity of Daphne blagayana Freyer (Thymelaeaceae)[J]. J Syst Evol, 2017, 55(5): 437 -445 .