本文采用ISSR分子标记方法分析了24份不同地区来源铁皮石斛种质资源的遗传多样性和亲缘关系。利用筛选出的7条ISSR引物对铁皮石斛基因组DNA进行PCR扩增，共获得92条DNA条带，其中多态性条带84条，多态性比率（PPB）为 91.3%。利用POPGENE 32软件计算得出平均观察等位基因（Na）为1.913 0，平均有效等位基因数（Ne）为 1.528 3，平均 Nei’s 基因多样性指数（H）为 0.310 0，平均 Shannon’s 信息指数（I）为0.465 0。利用NTSYSpc软件得出24份试验材料的遗传相似系数（GS）范围为 0.478 3~0.913 0，聚类分析结果表明24份人工栽培居群的铁皮石斛分为3类，暗示铁皮石斛种质具有较为丰富的遗传多样性。该研究为全面掌握铁皮石斛种质资源遗传背景，选育、引种和推广优良铁皮石斛品种奠定了可靠的理论基础。

The genetic diversity and genetic relationship of 24 Dendrobium candidum germplasms with different yields were studied by ISSR molecular markers in this study. Seven ISSR primers were screened to amplify genomic DNA of Dendrobium officinale by PCR. A total of 92 DNA bands were obtained, of which 84 were polymorphic, and the polymorphic ratio (PPB)was 91.3%.By POPGENE 32 analysis, the average of observed number of alleles(Na)is 1.913 0, effective number of alleles (Ne)is 1.528 3,Nei’s genetic diversity (H)is 0.310 0 and the Shannon’s information index(I)is 0.465 0. The genetic similarity (GS)of twenty four varieties by NTSYSpc software ranged from 0.478 3 to 0.913 0. Cluster analysis showed that 24 cultivated populations of Dendrobium officinale could be divided into three groups. The results showed that the genetic diversity of Dendrobium officinale germplasm resources was abundant. It provides a reliable theoretical basis for comprehensively understanding the genetic background, the selection, introduction and promotion of Dendrobium officinale in this research.