利用SRAP分子标记研究美洲海蓬子实生群体遗传多样性

Genetic Diversity of Halophyte Salicornia bigelovii

选取28株不同形态的海蓬子株系,调查植株高度、分枝夹角、果荚长度等生物性状,并采用SRAP技术对海蓬子株系进行遗传多样性分析。测定数据显示,海蓬子的不同株系在植株高度、分枝夹角、果荚长度均存在显著差异。SRAP标记多态条带比率(PPB)、Shannon多样性指数(I)以及Nei氏基因多样度(h)均显示海蓬子实生群体具有较为丰富的遗传多样性。SRAP标记相似系数变异范围为0.42～0.92。以相似系数平均值0.76为阈值,可将所有供试材料划分为11个亚类,表明海蓬子不同株系间存在明显的表型差异与遗传多样性。建议在实生群体内通过选择来培育海蓬子新品种。

In order to describe genetic relationships in Salicornia bigelovii lines, twenty-eight Salicornia bigelovii lines in the present study were tested for biological characters including height, legume length and branch angle. The plant height and legume length of 28 Salieornia lines were in the range from 11.34 cm to 28.75 cm and 1.37 cm to 7.20 cm, respectively. Branch angle of Salicornia lines ranged from 22. 5 ° to 88.5 °. The results of analysis of variation （ ANOVA ） showed that there were significant differences on height, legume length and branch angle among lines. Amplified with 9 pairs of sequence-related amplified polymorphism （SRAP） primers, 124 SRAP markers were screened to understand the genetic diversity in above lines. Salicornia bigelovii lines also expressed high genetic diversity in percentage of polymorphic bands （PPB）, Shannon＇ s information index （I） and Nei＇s gene diversity （h） calculated by software PopGene version 1.32. The SRAP-based genetic similarity （Gs） among 28 lines of Salicornia bigelovii ranged from 0. 42 to 0. 92 with a mean of 0. 76. The dendrogram con-structed after polymorphic SRAP data revealed that Salicornia bigelovii lines could be classified into 11 groups at 0. 76 similarity coefficient, suggesting high degree of genelic diversity in Salicornia bigelovii. Therefore, it was strongly suggested to develop new Salicornia bigelorii cuhivar by genetic improvement.