红花油脂相关性状与SSR分子标记的关联分析

Association Analysis of Oil-related Traits with SSR Molecular Markers in Safflower

红花(Carthamus tinctorius L.)是一种富含不饱和脂肪酸的重要油料作物。为寻找与红花油脂性状相关联的分子标记,本研究利用已经开发的多态性良好的48对SSR引物,系统分析了来自27个国家74份红花种质资源的遗传多样性和群体结构,并结合红花油脂相关性状的表型数据,应用TASSEL3.0中的一般线性模型(GLM,general linear model)和混合线性模型(MLM,mixed linear model)对红花油脂性状和标记进行关联分析。研究结果显示:48对SSR分子标记的多态性信息含量(PIC)变异范围为0.0632~0.3750,平均值为0.2937;基因多样性指数变异范围为0.0653~0.5000,平均值为0.3700。UPGMA聚类将74份红花分为3个类群,分别包括7份、52份和15份材料。群体结构分析结果显示,74份红花可分为3个亚群,各亚群分别包括7份、55份和12份材料。在显著水平P<0.05条件下,通过GLM和MLM两种模型都检测到了18个与油脂性状相关联的分子标记,各标记对表型变异的解释率变幅分别为5.42%~20.69%和4.35%~20.69%。两种分析方法相比,除标记Ct589和Ct178不同外,剩余16个标记在两种分析方法中都能检测到。研究表明:所选74份红花种质资源的群体遗传多样性丰富,结构差异性显著,适合用于红花油脂相关性状的关联分析。本研究为高含油量红花辅助育种提供了新的分子标记资源。

Safflower(Carthamus tinctorius L.),which serves as an important oil crop,contains higher content of the unsaturated fatty acids.Forty-eight SSR markers were used to unlock the genetic diversity and the population structure of 74 safflower germplasm resources from 27 countries.The association analysis using the general linear model(GLM)and the mixed linear model(MLM)was conducted to identify the molecular markers associated with oilrelated traits.The results showed that the polymorphism information content(PIC)value ranged from 0.0632 to 0.3750,with an average of 0.2937,and the genetic diversity index ranged from 0.0653 to 0.5000,with an average of 0.3700.The cluster analysis using UPGMA assigned 74 safflowers into 3 groups,including 7,52 and 15 genotypes,respectively.The population structure analysis suggested three subgroups consisting of 7,55 and 12 genotypes,respectively.At a significant level of P<0.05,18 markers associated with oil-related traits were detected by either GLM or MLM models,which explained the phenotypic variation with a range of 5.42%to 20.69% and 4.35% to 20.69%,respectively.Out of that,eighteen markers,except for Ct589 and Ct178,were detected by both approaches.Taken together,this study suggested an abundant genetic diversity and revealed several markers associating with oil-related traits,which provided the marker resource in future breeding for high-oil content safflower.