Abstract:

The fingerprints of 27Leymus chinensis(Trin.) Tzvel accessions from different regions in China were generated and their genomic DNA variations were assayed via amplified fragment length polymorphism (AFLP). A total of 537 DNA fragments were amplified ranging from 75－530 bp using 8 AFLP primer combinations, among which 89 (16.6%) were monomorphic and 329 (61.3%) were polymorphic. The average number of DNA band produced by each primer combination was 66.13 and the total polymorphic rate was 78.84%. PICs (polymorphic information contents) scores for AFLP ranged from 0.0－0.5 and the mean PIC was 0.216. PIC scores were maximum (0.5) for 8.5% of the AFLP markers. All the results revealed that there was rich polymorphism in genomic DNA of L. chinensis. A DNA molecular dendrogram was established for 27 L. chinensis genotypes based on genetic variation and UPGMA cluster analysis of 537 AFLP markers amplified by 8 primer combination, suggesting that the genetic variation with high frequency showed close correlation with their ecotopes and geographical distributions. Twenty seven L. chinensis genotypes could be divided into four groups. Among them the lower genetic relationship was shown. The reason of high genetic variation frequency in L. chinensis species and formation of varieties was discussed.

羊草种质基因组DNA的AFLP多态性研究
刘 杰 朱至清 刘公社* 齐冬梅 李芳芳
（中国科学院植物研究所，北京10093）

摘要: 羊草是禾本科牧草之王,在当前我国西部生态建设和草原畜牧业发展中发挥着重要作用.用AFLP方法对27份我国不同地区分布的羊草(Leymus chinensis (Trin.) Tzvel)材料进行了基因组DNA多态性分析,8对AFLP引物组合在27个不同羊草基因型中共扩增出537条带,产生出的DNA片段大小分布在75 bp-530 bp之间.其中单态性带89条,占16.6%,多态性带329条,占61.3%.平均每对引物组合扩增的DNA带数为66.13,总的多态性比率为78.84%.AFLP多态信息含量PIC值分布于0.0-0.5之间,平均PIC值为0.216,出现的PIC最大值(0.5)约占AFLP标记的8.5%,说明羊草基因组DNA的多态性比较丰富.以537个AFLP标记为原始数据,根据Nei和Li的方法对27份羊草材料进行遗传变异和聚类分析的结果表明:羊草种内有高频率的遗传变异发生,且与地理分布和生态环境密切相关;27份羊草不同基因型被划分为四大类群,不同类群相互间的遗传距离相对较大,在树状图中表现为较远的亲缘关系.对羊草种内遗传变异发生的原因和品种的形成进行了初步讨论.

关键词： 羊草； AFLP亲缘关系

Key words: Leymus chinensis, AFLP, genetic relationship