柳枝稷种质资源遗传多样性的ISSR分析

应用ISSR标记对138份柳枝稷种质的遗传多样性和遗传结构进行研究,为资源保护利用提供理论依据和技术支持。研究结果显示,1)从100个ISSR引物中筛选出16个条带清楚且稳定的引物,共扩增出220条谱带,其中,多态性谱带196条,多态性比率(PPB)为89.09%,平均每个引物扩增条带数为13.75条。2)POPGENE 1.32软件分析结果显示,138份柳枝稷基因多样性指数(H)为0.2498,Shannon指数(I)为0.3880,表明供试的种质间遗传多样性较丰富,遗传多样性水平较高。3)AMOVA 1.55软件方差分析结果显示,43.40%的遗传变异存在于生态型之间,56.60%遗传变异存在于生态型之内,说明遗传结构的变异主要存在于生态型之内。4)NTsys-pc 2.1软件进行UPGMA聚类分析和主成分分析(PCA),供试138份柳枝稷种质间Dice遗传相似系数(GS)值为0.4000~0.8818,平均值0.7237,结果表明,低地型材料聚为一大类,高地型材料聚为一大类。

Analysis on genetic diversity of germplasm resources of switchgrass (Panicum virgatum) as shown by ISSR

The inter-simple sequence repeat (ISSR) method was used to study the genetic diversity and genetic structure of 138 switchgrass accessions to provide information on how to improve the utilization of switchgrass germplasms. 1) Sixteen primers were selected from 100 ISSR primers, and a total of 220 bands were amplified. Of these bands, 196 were polymorphic (89.09%) and the average number was 13.75 per primer. 2) POPGENE analysis showed that the average information index of Shannon (I) was 0.3880 and gene diversity of Nei (H) was 0.2498, indicating a rich genetic diversity of switchgrass germplasm resources. 3) Analysis of AMOVA showed genetic variance within an ecotype was larger than that between ecotypes, while the genetic variance within an ecotype and between ecotypes was 56.60% and 43.40%, respectively. 4) Using NTsys-pc V2.1 software, the 138 accessions were clustered into two groups (lowland and upland ecotypes) by UPGMA clustering and principal component analysis (PCA) with the similarity coefficient ranging from 0.4000 to 0.8818 (average of 0.7237). In the upland ecotype, six subgroups were distinguished. Some cultivars and populations could not be grouped according to their pedigrees or collection area.