Delen Yavuz, Mural Ravi V, Palali-Delen Semra, Xu Gen, Schnable James C, Dweikat Ismail, Yang Jinliang
Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln NE USA.
Department of Agronomy, Horticulture and Plant Science South Dakota State University Brookings SD USA.
Plant Direct. 2024 Oct 9;8(10):e70010. doi: 10.1002/pld3.70010. eCollection 2024 Oct.
Sunflower ( L.) plays an essential role in meeting the demand for edible oil worldwide. The yield of sunflower seeds encompasses several component traits, including the disc diameter. Over three consecutive years, 2019, 2020, and 2022, we assessed phenotypic variation in disc diameter across a diverse set of sunflower accessions (N = 342) in replicated field trials. Upon aggregating the phenotypic data from multiple years, we estimated the broad sense heritability ( ) of the disc diameter trait to be 0.88. A subset of N = 274 accessions was genotyped by using the tunable genotyping-by-sequencing (tGBS) method, resulting in 226,779 high-quality SNPs. Using these SNPs and the disc diameter phenotype, we conducted a genome-wide association study (GWAS) employing two statistical approaches: the mixed linear model (MLM) and the fixed and random model circulating probability unification (farmCPU). The MLM and farmCPU GWAS approaches identified 106 and 8 significant SNPs located close to 53 and 21 genes, respectively. The MLM analysis identified two significant peaks: a prominent signal on chromosome 10 and a relatively weaker signal on chromosome 16, both of which were also detected by farmCPU. The genetic loci associated with disc diameter, as well as the related candidate genes, present promising avenues for further functional validation and serve as a basis for sunflower oil yield improvement.
向日葵（L.）在满足全球食用油需求方面发挥着重要作用。向日葵种子的产量包括几个组成性状，其中包括花盘直径。在2019年、2020年和2022年连续三年中，我们在重复的田间试验中评估了一系列不同向日葵种质（N = 342）花盘直径的表型变异。汇总多年的表型数据后，我们估计花盘直径性状的广义遗传力（ ）为0.88。使用可调谐测序基因分型（tGBS）方法对N = 274个种质进行了基因分型，共获得226,779个高质量单核苷酸多态性（SNP）。利用这些SNP和花盘直径表型，我们采用两种统计方法进行了全基因组关联研究（GWAS）：混合线性模型（MLM）和固定与随机模型循环概率统一法（farmCPU）。MLM和farmCPU的GWAS方法分别鉴定出106个和8个与53个和21个基因紧密相邻的显著SNP。MLM分析鉴定出两个显著峰值：一个位于第10号染色体上的强信号和一个位于第16号染色体上相对较弱的信号，这两个信号也都被farmCPU检测到。与花盘直径相关的遗传位点以及相关候选基因，为进一步的功能验证提供了有前景的途径，并为提高向日葵油产量奠定了基础。
