基于SSR标记的甜菜种质资源遗传多样性及群体结构分析

Analysis of genetic diversity and population structure of sugarbeet germplasm resources by SSR markers

【目的】拓展甜菜种质资源创新及利用途径,组配优良杂交组合,进一步提高育种工作效率。【方法】采用SSR分子标记技术,对70份甜菜资源材料进行遗传多样性及群体结构分析;采用CTAB法提取甜菜基因组DNA,用多态性好、条带清晰的12对SSR引物对提取的70份甜菜基因组DNA进行PCR扩增,扩增产物使用6%变性聚丙烯酰胺凝胶电泳检测,并对检测结果进行统计分析。【结果】在70份甜菜资源材料中扩增出52个等位基因,每对引物的等位基因数为2~6个,观察到的平均等位基因数为4.33个;观测杂合度(Ho)为0.06~0.60,平均为0.22;期望杂合度(He)为0.15~0.97,平均为0.69,表明供试材料遗传多样性较丰富;多态信息含量(PIC)为0.10~0.96,平均为0.65。根据SSR标记数据进行群体结构分析,在K=6时,将70份甜菜种质分为6个亚群,与主成分分析结果基本对应。【结论】该研究进一步反映了70份甜菜资源材料的遗传多样性、遗传背景及内在的遗传结构,为今后育种工作中甜菜资源材料的选择和利用提供了理论依据。

【Objective】In order to develop the way of innovation and utilization of sugarbeet germplasm resources,make the excellent hybrid combinations and improve the efficiency of breeding.【Methods】The genetic diversity and population structure of 70 sugarbeet germplasm resources were analyzed by SSR molecular markers.The sugarbeet genomic DNA was extracted by CTAB method,and the genomic DNA of 70 sugarbeet germplasm resources was amplified by PCR using 12 pairs of SSR primers with good polymorphism and clear bands,the amplified products were detected by 6%denatured polyacrylamide GEL electrophoresis,and the results were statistically analyzed.【Results】A total of 52 alleles were amplified from the resources,each pair of primers could catch 2-6 alleles,the average number of the alleles was 4.33,and the heterozygosity(Ho)was 0.06-0.60,the average value was 0.22.The expected heterozygosity(He)was 0.15-0.97,the average value was 0.69,which indicated that the genetic diversity of the resources was rich,and the polymorphism information content(PIC)was 0.10-0.96,and the average value was 0.65.According to SSR marker data,70 sugarbeet germplasm resources were divided into 6 subgroups at K=6,which was essentially consistent with the result of principal component analysis.【Conclusion】The study further reflected the genetic diversity,genetic background and inherent genetic structure of the 70 sugarbeet germplasm resources materials,and provided a theoretical foundation for the selection and utilization of the materials in future breeding.