多倍体无籽罗汉果及其亲本遗传背景的RAPD分析

RAPD Analysis of Polyploidy Seedless Siraitia grosvenorii and Their Parents

通过RAPD分子标记分析15份多倍体无籽罗汉果及其亲本的遗传背景。结果表明，多倍体无籽罗汉果及其亲本间的相似性系数为0．6858～0．9193，子代与父本间的遗传距离均高于其与母本间的，说明了F1代从母本中继承到更多的遗传物质，遗传上倾向于母本。子代与亲本间的平均遗传距离小于或大于亲本与亲本间的，随亲本的组配及相应的子代而定；结合聚类和双变量主坐标分析。由此可知，基本上子代和母本先排列后聚在一起，而且母本、父本和子代彼此之间遗传距离较近的聚在一类；所以整体上体现了“子似亲”的遗传现象。这为选育兼具多倍体优势和杂种优势的无籽罗汉果新品种（系）的亲本组配提供了遗传背景依据。

Genetic background of polyploidy seedless Siraitia grosvenorii and their parents were stud- ied with RAPD （Random Amplified Polymorphic DNA） molecular marker technique. The results showed that the genetic similarity coefficients between the offspring and parents were from 0. 685 8 to 0. 919 3. The average coefficient between Fi generation and tetraploid female parent was higher than that between Fa generation and diploid male parent, indicating that the F1 generation obtained more genetic substance from female parent than that from male parent. The Fi generation was genetically toward the female parent. The average coefficient between F1 generation and the parents was either higher or lower than that between two parents. According to dendrogram analysis and double principal coordinate analysis, offspring and female parent were clustered together. If genetic distance of male parent, female parent and offspring was close, they would be grouped together too. Therefore, the F1 generation displayed the genetic phenomenon of ＂offspring is similar to parents＂. The information will be helpful in the breeding of new polyploidy seedless Siraitia grosvenorii with strong beterosis and multiploid superiority.