目的评价山药资源的多样性，为山药品种鉴定及亲缘关系的研究提供科学依据。方法以8个山药栽培居群中的21个山药品种为试材，进行相关系列扩增多态性（SRAP）分析，Popgene1.32软件计算遗传参数，UPGMA方法构建亲缘关系聚类图。结果相关系列扩增多态性引物共检测到309条清晰条带，其中多态性条带289条；Nei基因多样性指数（H）为0.2881、Shannon信息指数为（I）0.4416、居群间基因多样性（Ht）为0.2891，阐明了山药居群间具有很高的多样性；居群内以河南温县薯蓣居群多样性最高，PPB为35.92％，而福建三明（FJSM）和浙江高楼（ZJRG）山薯居群多样性最低（PPB＝0％）；居群间基因分化系数Gst为0.8658、基因流（Nm）为0.0775，揭示山药居群间遗传变异大于居群内遗传变异；8个居群间的遗传距离在0.0498～0.4879，因栽培物种的不同被聚为4类；相关系列扩增多态性标记可将21个山药品种分别归属到薯蓣、参薯、褐苞薯蓣、山薯种内。结论山药品种呈现较高遗传多样性，4种基原山药种间遗传差异较大，相关系列扩增多态性是鉴别我国山药品种的有效方法。

OBJECTIVE To investigate the genetic diversity of yam resources in China and provide reliable molecular evidences for cultivar identification and genetic relationship. METHODS Sequence-related amplified polymorphism (SRAP) was applied to detect the genetic diversity of 21 yam cultivars from eight cultivated populations, Popgene software (version 1.32) was used to calculate genetic parameters, UPGMA clustering was carried out using Mega software (version 4.1), and principal component analysis was performed with the help of Ntsys-pc (Version 2.1) program. RESULTS Three hundreds and nine bands were amplified by 20 SRAP primer combinations,of which 289 bands were polymorphic. The Nei′s gene diversity index (H＝0.288 1), Shannon′s information index (I＝0.441 6) and total genetic diversity (Ht＝0.289 1) revealed a relatively high genetic diversity level among yam populations. Within populations,HNWX population showed the highest genetic diversity (PPB= 35.92%),whereas the lowest diversity (PPB=0) was observed in FJSM and ZJRG populations. The genetic differentiation coefficient (Gst=0.865 8) and genetic flow (Nm=0.007 5) indicated that the genetic diversity among populations was higher than that of within populations. A well-separated groups coupling with cultivated species was formed according to the genetic distance (GD) ranging from 0.049 8-0.487 9 of the investigated populations. Twenty-one investigated cultivars could be distinguished and be effectively grouped into four origins, i.e., Dioscorea opposita Thunb., Dioscorea alata Linn., Dioscorea persimilis Prain et Burkill. and Dioscorea fordii Prain et Burkill.. CONCLUSION The genetic diversity level of yam resources is high,and relatively high genetic variation exists among four yam species. SRAP marker is an effective method to identify and classify numerous yam cultivars.