沙田柚杂交后代群体的SSR鉴定与遗传多样性分析

【目的】利用SSR标记对沙田柚杂交后代群体进行杂种鉴定和遗传多样性研究,为柑橘种质创新和遗传改良提供技术、材料和理论支持。【方法】利用SSR技术分析沙田柚两个杂交组合159株后代的杂种性质,采用UPGMA聚类分析法分析后代群体和亲本的遗传关系。【结果】4对引物可以从104株沙田柚×强德勒柚的杂交后代鉴定出103株真杂种,鉴定率达到99.04%,且在引物AGC9的扩增图谱中有70个单株出现了双亲都没有的新条带;5对引物可鉴定出沙田柚×红江橙的全部杂交后代均为真杂种,一个纯合显性标记AAT12被发现,在引物GA18和AGC9的扩增结果中出现了亲本位点的缺失;UPGMA聚类分析结果显示,两个杂交组合后代群体均出现较显著的遗传变异,两个组合的遗传多样性也有较大的差异。【结论】SSR标记适合柑橘杂种的鉴定和遗传多样性分析,杂交是获得柑橘遗传变异株系的有效途径。

Identification and Genetic Diversity of Hybrid Progenies from Shatian Pummelo by SSR

【Objective】 SSR markers were used to identify and study the genetic diversity of hybrid progenies from crosses of Shatian pummelo as female, which can provide technical and materials’ support and a theoretical basis for innovating germplasm and genetic improvement of citrus. 【Method】 The hybrid nature of 159 offsprings from the two cross combinations of Shatian pummelo was analyzed, and the genetic relationship between parents and offsprings was analyzed with UPGMA. 【Result】 One hundred and three hybrids was identified from 104 F1 seedlings of ‘Shatianyou’ × ‘Chandler’ pummelo by 4 pairs SSR primers, the identification rate was 99.04%, and 70 progenies had non-parent markers in primer AGC9. All the offsprings from ‘Shatianyou’בHongjiangcheng’ were proved to be hybrids with 5 pairs SSR primers, one homozygous maker AAT12 was obtained, and some markers were absent in 55 F1 seedlings in primer GA18 and AGC9. The cluster analysis of SSR data indicated that the genetic variation of hybrids from the two cross combinations was obviously, and the genetic diversity between the two combinations of crosses was obviously different.【Conclusion】 The identification of hybrids and genetic diversity of citrus can be assessed efficiently by SSR markers, and the cross breeding is an effective way to obtain variant strains.