半野生棉棉仁含油量与SSR标记的关联分析

为探究半野生棉群体材料的遗传变异和群体结构,挖掘与含油量相关的标记位点,利用215对SSR引物,对89份半野生棉自然群体进行遗传多样性、群体结构和亲缘关系分析,并进行棉仁含油量性状与标记的关联分析。结果表明,位点多态信息含量(PIC)为0.0222~0.7390,平均为0.3452;基因型多样性(H′)介于0.0616~1.4412,平均为0.5614。群体结构分析将89份材料分为2个亚群,群体结构简单,遗传变异比较丰富,可以用于半野生棉目标性状的关联分析。应用关联分析,在3个年份环境下重复检测出12个与棉仁含油量显著相关的位点(P0.05),这12个位点可能与含油量性状存在稳定的关联,可为棉仁含油量性状的分子标记辅助选择提供依据,为开展半野生棉其它性状的关联分析提供参考。阔叶棉141平均棉仁含油量为41.90%,为高油份含量品种的遗传改良提供理想材料。

Association Analysis of Cottonseed Kernel Oil Content with SSR Markers in Gossypium hirsutum L. races

The study objectives were to estimate genetic diversity, population structure, and identify loci associated with cottonseed oil content in Gossypium hirsutum L. To do this, 89 G. hirsutum L. races accessions, and 215 pairs of SSR molecular markers were compared. Genetic diversity, population structure, and association mapping analysis were conducted using different software packages. The results showed that the polymorphism information content of the SSR markers ranged from 0.0222 to 0.7390 with a mean of 0.3452. The Shannon-Wiener diversity index(H'') ranged from 0.0616 to 1.4412 with a mean of 0.5614. Population structure analysis divided the 89 accessions into two subpopulations. The 89 accessions had extensive genetic variation and a simple population structure, which revealed the natural population to be representative for further association analysis of quantitative traits in cotton. Association analysis showed that 12 markers were significantly associated with cottonseed oil content(P＜0.05) over 3 successive years. Of all the accessions, LAT141 had the highest average cottonseed Kernel oil content (41.90 %), revealing its potential to be exploited as a good source of high oil content. The findings of this study could be used in genetic improvement of cottonseed oil content of cultivated Gossypium species through marker assisted selective breeding programs, and could also be utilized as a reference database for mapping other agronomic qualities of semi-wild accessions.