is a conserved regulator controlling plant architecture and yield traits in common wheat ( L.).

Plant architecture is a crucial influencing factor of wheat yield and adaptation. In this study, we cloned and characterized , a homologous gene of the rice ideal plant architecture gene in wheat. homoeologs (, and ) exhibited similar expression patterns, and they were all preferentially expressed in stems at the elongation stage and in young spikes. Moreover, the expression level of was higher than that of and . Overexpression of in wheat resulted in significant changes in plant architecture and yield traits, including decreased tiller number and increased kernel size and weight. Three haplotypes were identified in Chinese wheat core collection, and haplotype-based association analysis showed that were significantly correlated with fewer tillers, larger kernels and higher kernel weights in modern cultivars. The haplotype effect resulted from a difference in expression levels among genotypes, with leading to higher expression levels than . As favorable haplotypes, underwent positive selection during global wheat breeding over the last century. Together, the findings of our study provide insight into the function and genetic effects of and provide a useful molecular marker for wheat breeding.