Biodiv Sci ›› 2003, Vol. 11 ›› Issue (2): 91-99.DOI: 10.17520/biods.2003013

• 论文 •     Next Articles

Allozyme variation in Sophora moorcroftiana , an endemic species of Tibet, China

ZHAO A-Man1,LIU Zhi-Min2*,KANG Xiang-Yang1,ZHOU Shi-Liang3   

  1. 1 College of Biological Sciences and Technology,Beijing Forestry University,Beijing 100083
    2 Insitute of Applied Ecology,Chiese Academy of Sciences,Shenyang 110016
    3 Laboratory of Systematic and Evolutionary Botany,Institute of Botany,Chinese Academy of Sciences,Bejing 100093
  • Received:2002-11-15 Revised:2002-12-25 Online:2003-03-20 Published:2003-03-20
  • Contact: LIU Zhi-Min

Abstract: The genetic diversity of ten populations of Sophora moorcroftiana in the middle reaches of the Yarlung Zangbo River, Tibet, China was assessed using allozyme analysis by horizontal sliceable starch gel electrophoresis. Twenty four loci (46 alleles) of 13 enzyme systems demonstrate low levels of genetic variation within populations, with the value of Pp=25.0%~37.5%,Ap=1.3~1.7 and Hep=0.112~0.169. At the species level, the genetic diversity of S. moocroftiana (Ps=37.5%, As=1.9, Hes=0.171) was lower than the mean value of angiosperms of long lived woody species (Ps=59.5%,As=2.10,Hes=0.183). Wright′s F statistics analysis indicated that FIS, a measure of the deviation from random mating within the 10 populations, was -0.0071, suggesting deviation from Hardy-Weinberg equilibrium and a slight heteroygote excess in some populations. The higher level of differentiation (FST=0.1748) among populations than those of other long lived woody plants may result from habitat fragmentation and low levels of gene flow (Nm=1.1802) caused by environmental deterioration and human disturbance, including over felling and over-grazing. It was worth noting that populations H2 (Xietongmen), H31 (Jiangdang1), H32 (Jiangdang2), and H5 (Langsailing) harbored the majority of alleles and had high levels of genetic diversity, suggesting that these populations in particular should be conserved in situ.