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银叶真藓是世界广布种.对于分布在中国新疆维吾尔自治区不同地理居群的银叶真藓的遗传结构及遗传多样性的研究还未见报道.本研究以采集的新疆地区18个居群的银叶真藓共47株植物样品,采用改良的快速提取法提取随机单株植物总DNA,运用分子生物学技术分析银叶真藓居群的遗传多样性.研究结果表明:新疆不同地理居群银叶真藓nrDNA ITS序列可分为35种单倍型,存在537个变异位点;分子变异分析(AMOVA)显示有88.76％的遗传变异发生在居群间水平,居群内部的遗传变异为11.24％,银叶真藓居群间的遗传分化程度大于居群内的遗传分化.居群遗传变异的分化系数(Fst)为0.887 59,基因流值(Nm)为0.063 3,由于Nm值小于1,可以说明各居群间的基因流低.单倍型多态性水平(Hd)为0.982±0.010,核苷酸多态性水平(Pi)为0.170 87±0.02867.“,”Bryum argenteum Hedw.is a cosmopolitan moss.We have no information on its genetic diversity and population genetic structure in Xinjiang Uygur Autonomous Region,China.Therefore,the present population genetic study was performed to provide data on population genetic structure,potential gene flow in B.argenteum in Xinjiang.We studied 47 randomly selected plants from 18 geographical populations by using the nrDNA internal transcribed spacer (ITS) molecular markers.The results showed that in the 18 B.argenteum populations there were total of 35 haplotypes,and 537 variable sites existed.ITS sequence analysis of molecular variance (AMOVA) showed that genetic variation among populations was 88.76％,genetic variation within populations was 11.24％,and the degree of genetic differentiation among populations was greater than the genetic differentiation within populations.Genetic differentiation (Fst) was 0.887 59;Nm=0.063 3,Nm＜l,indicated B.argenteum of Xinjiang had limited gene flow among these populations.The haplotype diversity level was from 0.972 to 0.992.The nucleotide diversity level ranged from 0.142 2 to 0.199 54.