关键词: 蜡梅, 天然群体, 遗传多样性, SRAP标记

Abstract: The genetic diversity and genetic structure of natural populations of Chimonanthus praecox(L. ) L ink, were analyzed using Sequence-related Amp lified Polymorphism ( SRAP) markers. One hundred and fifty accessions from 5 natural populations were used in this study. Seven SRAP primer combinations
revealed 170 legible bands of which 41 were polymorphic markers. The average proportion of polymorphic loci PPL was 83.41%. Gene diversity ( h) was from 0.21 to 0.25 ( average 0.22) , Shannonps Information index
( I) was 0.34, coefficient of genetic differentiation (Gst) was 0.17 and the mean of gene flow estimated(Nm) was 2.40. The results of AMOVA indicated that the variance components within populations and among populations contributing to total genetic variance were 79189% and 20111%, among regions was 32.39% and within regions were 67.61%. There was obvious genetic differentiation among populations and among regions. UPGMA cluster analysis based on Nei's genetic distance indicated that the genetic distances were
closely related to corresponding geographic distances among populations, 22wayMantel testMatrix correlation r was 0.89. Conservation and utilization strategies for the species should be therefore emphasized on conserving
asmany as possible the existing populations, and selecting genetic diversitywithin populations considering the current conditions of severe population fragmentation and losses.

Key words: Chim onanthus praecox (L.) Link, natural population, genetic diversity, sequence-related amplified polymorphism ( SRAP)