应用RAMP分子标记探讨拟鹅观草属的种间关系

采用RAMP (random amplified microsatellite polymorphism) 标记技术, 分析了拟鹅观草属9种1亚种和鹅观草属6 种植物之间的遗传变异和亲缘关系。33 个引物组合产生的310 条DNA扩增片段中, 286条(92 25%) 具有多态性, 每个引物组合产生5~13条多态性带, 平均为8 67条。利用310个RAMP标记, 在NTSYS pc软件中, 计算Jaccard遗传相似系数, 建立UPGMA聚类图。结果表明: (1) 物种间遗传差异明显, 具有丰富的遗传多样性; (2) 阿拉善鹅观草和大丛鹅观草与拟鹅观草属的物种聚类在一起, 表明它们与拟鹅观草属的亲缘关系较近, 而与本试验所分析的另外4个鹅观草属物种的亲缘关系较远; (3) RAMP分子标记可以将拟鹅观草属的物种分开, 而且形态相似、地理分布相同或相近的物种聚类在一起;(4) RAMP结果与形态学和细胞学的分析结果一致, 表明RAMP标记是评价拟鹅观草属种间关系十分有效的方法。

Relationships among Pseudoroegneria Species Based on RAMP

Relationships and genetic variation among nine species and one subspecies of Pseudoroegneria and six species of Roegneria were analyzed by using RAMP (random amplified microsatellite polymorphism) markers.A total of 310 products were amplified by 33 primer combinations,among which 286 (92.25%) products were found to be polymorphic.5～13 polymorphic bands were produced by each primer combination,with an average of 8.67.The data of 310 RAMP bands were used to generate Jaccard's similarity coefficients and to construct a dendrogram by means of UPGMA in the NTSYS-pc program.It was concluded as follows:(1) Distinct genetic differences and extensive genetic diversity were present among the species;(2) 2 species in Roegneria,i.e.,R.alashanica and R.magnicaespes,and 10 accessions in Pseudoroegneria were grouped together,indicating that the two Roegneria species were closer to the species of Pseudoroegneria than to the other four species of Roegneria analysed in this study;(3)Pseudoroegneria species were separated clearly from each other based on RAMP markers.Meanwhile,the species with similar morphological characters and the species from the same areas or neighboring geographical regions were clustered together;(4)RAMP results were basically comparable with those obtained from morphological and cytological studies.It is concluded that RAMP is a useful method to assess the genetic relationships among Pseudoroegneria species.