Identification and Validation of Quantitative Trait Loci for Grain Size in Bread Wheat (Triticum aestivum L.)

Grain width (GW) and grain length (GL) are crucial components affecting weight. Dissection of their genetic control is essential for improving yield potential in wheat breeding. Yangmai 12 (YM12) Yanzhan 1 (YZ1) two elite cultivars released the Middle Lower Yangtze Valleys Wheat Zone (MLYVWZ) Yellow-Huai River (YRVWZ), respectively. One biparental population derived from YM12/YZ1 cross was employed to perform QTL mapping based on data four environments over years detect quantitative trait loci (QTL) GW GL. A total eight were identified chromosomes 1B, 2D, 3B, 4B, 5A, 6B. Notably, QGW.yz.2D co-located with QGL.yz.2D, QGW.yz.4B QGL.yz.4B, increasing GW/GL allele YZ1, explained 12.36–18.27% 13.69–26.53% phenotypic variations GL, YM12, 10.34–11.95% 10.35–16.04% variation QGL.yz.5A, GL 10.04–12.48% Moreover, positive alleles these three regions could significantly increase thousand-grain weight, QGW.yz.4B/QGL.yz.4B QGL.yz.5A did not show significant negative effects number per spike. QGW.yz.4B/QGL.yz.4B, have been reported. These then further validated using Kompetitive Allele-Specific PCR (KASP) markers 159 cultivars/lines MLYVWZ YRVWZ. Combining major increased Eleven candidate genes associated encoding ethylene-responsive transcription factor, oleosin, osmotin protein, thaumatin protein identified. Three KASP reported here will be helpful developing new high stable yields.