Biodiv Sci ›› 2014, Vol. 22 ›› Issue (3): 375-384.DOI: 10.3724/SP.J.1003.2014.14013

• Orginal Article • Previous Articles     Next Articles

Microsatellite genetic diversity and fine-scale spatial genetic structure within a natural stand of Liriodendron chinense (Magnoliaceae) in Lanmushan, Duyun City, Guizhou Province

Aihong Yang1,2, Jinju Zhang3, Hua Tian1, Xiaohong Yao1,*(), Hongwen Huang1   

  1. 1. Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074
    2. University of the Chinese Academy of Sciences, Beijing 100049
    3. College of Life Sciences, Wuhan University, Wuhan 430070
  • Received:2014-01-14 Accepted:2014-04-25 Online:2014-05-20 Published:2014-06-04
  • Contact: Yao Xiaohong

Abstract:

The Chinese tulip tree (Liriodendron chinense), an endangered species scattered throughout subtropical China and northern Vietnam, suffers from severe habitat fragmentation. Understanding the genetic diversity and fine-scale spatial genetic structure (SGS) of fragmented populations is critical for developing successful conservation strategies for endangered species. In this study, we investigated the population genetic diversity and fine-scale spatial genetic structure in a wild, fragmented population of L. chinense using 13 polymorphic microsatellite loci. No significant differences in genetic diversity were found among habitat fragments or age classes (P > 0.05). Two genetically heterogeneous subpopulations were revealed through Bayesian assignment analysis and Principal Coordinates Analysis (PCoA). Significant SGS was found within the whole population within 200 m, while weak spatial aggregation of related individuals in the two subpopulations was found within 20 m. SGS intensity was weak in this population (Sp = 0.0090), and it was stronger in the village subpopulation (Sp = 0.0067) than in the hill subpopulation (Sp = 0.0053). Liriodendron chinense is a predominantly outcrossing tree and its winged seeds are wind-dispersed, a fact that may reduce SGS intensity in the species. Furthermore, low population density and flat hypsography also likely influence the SGS of L. chinense. The presence of significant heterozygote deficiency in the population (FIS = 0.099, P < 0.01) suggests a genetic signal of habitat fragmentation. Therefore, measures for promoting pollen flow should be taken for in situ conservation. For ex situ conservation, individuals should be sampled at 20 m apart to efficiently capture genetic diversity of wild populations.

Key words: Liriodendron chinense, habitat fragmentation, genetic diversity, spatial genetic structure, endangered species