E-mail: sbliu@sdau.edu.cn

Wheat is one of the major staple food crops around the world, the genetic dissection of important traits is essential to identify and use novel genes to continuously increase grain yield to ensure the global food security.

In this study, a large-scale genome-wide association study (GWAS) was conducted using a panel of 768 wheat cultivars and breeding lines that were genotyped by genotyping-by-sequencing and 599 genomic loci for 18 important traits including 12 yield related traits, resistance to stripe rust, leaf rust and powdery mildew, yellow mosaic virus, cold tolerance and pre-harvest sprouting were identified.

Among which, some of the QTLs modulate plant height, spike and grain shape and size were validated in bi-parental populations, and the candidate genes underlying the QTL were cloned with the function validated by genome editing. KASP assays were also developed for some of the major QTLs identified by GWAS, which can facilitate the fine mapping and marker assisted selection of the targeting QTLs.

Genomic prediction models for each trait were constructed based on the significant SNPs that were highly associated with those traits with high prediction accuracies. Results from this study demonstrated that high resolution GWAS using a large population and high-density marker can not only lay a solid foundation for large-scale QTL fine mapping and candidate gene identification, marker assisted breeding, but also increase the prediction accuracy for genomic selection in wheat.