大花紫薇与紫薇杂交F1群体表型评价及分子标记连锁分析

Phenotypic Assessment and Linkage Analysis of Main Ornamental Traits of Lagerstroemia speciosa × L.indica to SSR Markers

以大花紫薇(Lagerstroemia speciosa)为母本,紫薇(L. indica)品种‘Sacramento’为父本杂交构建的F_1群体为材料,对株高、冠幅、叶长、叶宽、花径、瓣爪长、花序长、花序宽、主枝GSA、生长习性、花芽形状、花芽缝合线、单色花颜色和复色花主副色共14个主要观赏性状进行了统计和分析,评价了F_1群体的遗传多样性,对主要观赏性状与SSR标记进行了连锁分析。结果表明:(1)株高等9个主要观赏性状的变异系数范围为14.58%～48.33%;生长习性以半直立和开展居多;花芽、花色表型无明显分离;主要观赏性状彼此之间呈现一定的相关性。(2)SSR标记多态信息含量(PIC值)的范围为0.20～0.59,平均值为0.43;Shannon’s信息指数分布范围为0.38～1.13,平均值为0.82;平均期望杂合度和观察杂合度分别为0.52和0.53:说明F_1群体遗传多样性程度中等。(3)8个SSR标记与8个性状共22个组合显著相关,解释率范围为3.46%～16.02%。

Using F 1 population of Lagerstroemia speciosa×L. indica‘Sacramento’,the genetic variation of fourteen main ornamental traits were analyzed,diversity of F 1 population was assessed,and 19 SSR markers were employed to perform the linkage analysis between the main ornamental traits and SSR markers. The results showed that the variation coefficients of all nine main ornamental characteristics were more than 10% and ranged from 14.58%–48.33%. The growth habits of F 1 seedlings were mostly semi-erect and explanate. The phenotype of flower bud and flower color had no obvious separation. There were correlations between traits. The value of polymorphism information content(PIC)ranged from 0.20 – 0.59 with a mean of 0.43. Shannon information index ranged from 0.38 – 1.13,and the average value was 0.82. The average expected heterozygosity was 0.52 and the observed heterozygosity was 0.53,indicating a medium value of genetic diversity in the F 1 population. Eight SSR markers were detected,which have significant correlation with eight main ornamental traits,and the interpretation ratio ranged from 3.46% – 16.02%.