Abstract: Pennisetum and Arundo are important species of Juncao， and some of them have the problems in name confusion and inaccurate chromosome number. In this study， chromosome sectioning technology， SRAP and SSR molecular markers were used to identify the number of chromosomes and analyze the genetic diversity of 22 materials of Pennisetum and 1 species of Arundo （Arundo donax ‘Lyuzhou No.1’）. The results of chromosome counting showed that the chromosome number of Pennisetum was 28， all of them were tetraploid， while the chromosome number of Arundo donax ‘Lyuzhou No.1’ was 110. A total of 296 bands were amplified by twelve pairs of SRAP primers and six pairs of SSR primers， including 277 polymorphic bands. The polymorphic rate was 95.5%. The genetic distance ranged from 0.061 to 0.905. The cluster analysis showed that 23 materials were classified into 7 groups with a genetic similarity coefficient of 0.77. The first category included 13 materials， including （P. glaucum×P. purpureum）×P. purpureum ‘Guimu No.1’， P. purpureum×P. tyhoideum ‘RY No. 4’， P. glaucum×P. purpureum-FD and so on. P. purpureum ‘Mott’， P. purpureum ‘Purple’ and P. purpureum- JC-ZJ were clustered into the second， third and sixth categories， respectively. P. purpureum ‘Guiminyin’ and P. purpureum from Xichang were clustered into the fourth category. The remaining four P. purpureum were clustered into fifth category. Arundo donax ‘Lyuzhou No.1’ was clustered into the seventh category at the bottom， which had the farthest relationship with other Pennisetum materials. Through chromosome number identification and molecular markers， the 22 materials of Pennisetum and 1 material of Arundo were accurately identified and the genetic relationship between them was analyzed， which provided some reference for standardizing the names of market materials and variety breeding.

Key words: Pennisetum, Arundo, Chromosome number, SRAP, SSR, Genetic diversity

摘要： 狼尾草属（Pennisetum）和芦竹属（Arundo）均为菌草的重要组成植物，其中部分材料存在名称混乱以及染色体数目不准确的问题。本研究利用染色体制片和SRAP与SSR两种分子标记对22份狼尾草属材料和1份芦竹属材料（‘绿洲1号’菌草）进行染色体数目鉴定和遗传多样性分析。结果表明：22份狼尾草属材料的染色体数目均为28条，为四倍体，‘绿洲1号’菌草则为110条。18对引物共扩增出296条带，其中多态性条带277条，多态性比率为95.5%，遗传距离在0.061~0.905之间。聚类分析表明，23份材料在遗传相似系数0.77处分为七大类：第Ⅰ类包括‘桂牧1号’杂交象草、RY No. 4、杂交狼尾草-FD等13份材料；‘摩特’矮象草、‘紫色’象草及菌草-ZJ分别聚为第Ⅱ、Ⅲ、Ⅵ类；‘桂闽引’象草与象草-XC聚为第Ⅳ类；剩余四份象草聚为第Ⅴ类；‘绿洲1号’菌草在最底部单独聚为第Ⅶ类，与其他狼尾草属材料关系最远。本研究准确鉴定了23份材料的染色体数目及其亲缘关系，为规范市场材料名称以及品种选育提供一定参考。

关键词: 狼尾草, 芦竹, 染色体数目, SRAP, SSR, 遗传多样性