Collectively, our data demonstrated that TaFlo2-A1, like the OsFlo2 gene in rice, is associated with TGW in wheat. Furthermore, the lack of association of TaFlo2-A1 with GpS suggests that the high TGW of the examined genotypes is primarily due to the positive haplotype (TaFlo2-A1b) for high TGW instead of loci for low number of kernels per spike and/or low grain yield.