柚类资源及其近缘种SSR标记的分子评价

采用31对SSR引物对122份柚类种质资源及其近缘种的遗传多样性进行了研究.31对SSR引物可以检测到335个等位基因变异,平均每个位点可检测到9.85个等位基因.每个位点多态性信息指数(PIC)平均值为0.7085.从这些引物中有效地筛选出21对高信息量SSR引物,与31对引物在122份柚类资源间遗传关系达到极显著相关(r=0.99104).柚类资源及其近缘种等位基因平均数(A)、平均杂合位点百分比(P)、SSR表型杂合度(H0)分别为2.8、83.54%、0.524.用UPGMA方法将122份研究材料分成7个组群,110个柚类品种在相似系数0.712时可细分成18个亚组,分类结果有利于今后有目的地利用这些丰富育种材料的遗传背景.图3表2参21

Molecular Evaluation of Pummelo Germplasms and Its Relatives Using SSR Markers

The genetic diversity of 122 germplasms of pummelo and its relatives was studied using 31 pairs of SSR primers. The 31 SSRs were polymorphic and a total of 335 alleles were detected, resulting in a mean number of 9.85 alleles per locus. The polymorphic information content (PIC), on an average, was 0.708 5 per primer. From these markers, 21 pairs of SSRs of high PIC were selected, and the relationship among 122 pummelo germplasms and its relatives was greatly correlative with 31 Pairs of SSRs (r=0.991 04). The mean number of alleles per locus (A), percentage of polymorphic loci (P) and direct count heterozygosity (H_ 0 ) assessed for each genotype, revealing considerable differences among the 122 genotypes, were 2.8, 83.54 and 0.524, respectively. The 122 germplasm of pummelo and its relatives could be clustered into seven groups with UPGMA method, in which the 110 pummelo accessions could be further divided into eighteen subgroups at similarity coefficient of 0.712. Fig 3, Tab 2, Ref 21