Identification and Validation of Stable Loci Underlying Productivity-Related Traits in Common Wheat

The genetic architecture of wheat yield-related traits is complex due to their polygenic control, relatively low heritability, and strong genotype-environment interactions. Commonly used characteristics of wheat productivity include thousand-grain weight (TGW), grain weight per ear (GWE), and grain number per ear (GNE). To identify stable loci associated with productivity-related traits in common wheat, we performed QTL analysis using two mapping populations derived from crosses between contrasting cultivars. The populations were phenotyped for GNE, GWE, and TGW over two years. In addition, GWAS was conducted using a cultivar panel phenotyped for yield and GWE over ten years, and for GNE, GWE, and TGW over two years. The most reproducible loci were located on chromosomes 2D, 4A, 5A, 5B, 6A, 6B, and 7A. From these regions, 16 SNPs were selected for KASP marker development. Validation in an independent panel of 296 spring common wheat varieties phenotyped over three years identified three most informative markers: wsnp_Ex_c16175_24619793 (4A), wsnp_Ex_c2171_4072995 (5A), and BS00034554_51 (6B), all consistently associated with TGW and additionally associated with GWE, GNE, or yield in individual years. These markers may be useful for marker-assisted selection of wheat productivity-related traits.