In order to identify QTLs for 1000-grain weight and its main component traits in wheat, a high-density genetic link map was constructed using a F8:9 recombined inbred line (RIL) population as material and exploiting the single nucleotide polymorphism (SNP) as well as PCR-based molecular markers, and to go a step further, QTL mapping for 1000-grain weight, grain length, and grain width in wheat was conducted. The linkage map was composed of 1257 loci formed by the 3916 markers, including 143 SSR

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... markers and 3773 SNP markers, which were distributed on 22 chromosomes (2A chromosome formed a break point) with the total length of 2291.6 cM and the average genetic distance between loci of 1.82 cM. A total of 41 qualitative trait loci (QTLs) on 19 chromosomes were detected, with contributions to phenotypic variance ranged from 3.59–58.49% for each QTL. Among these QTLs, two were detected in four environments, six in three environments, and 14 in two environments. Fifteen important loci with multi-effect were mapped on 9 chromosomes 1B, 2B, 3A, 4B, 5A, 5B, 6A, 7A, and 7B, involving 37 QTLs that accounted for 90.2% of total numbers of QTLs detected. Of these 15 loci, including one on chromosome 7A flanked by the markers Tdurum_contig77759_5 and BS00062425_51, which consisted of QTLs controlling TGW, GL, and GW and explained 4.2 to 58.49% of the phenotypic variation in these traits. Thus, the chromosome intervals of the 15 loci were important areas controlling the expression of 1000-grain weight and its main component traits in wheat.