LAUSR

Domestication and diversification have profound impact on crop genomes. Originated from Africa and subsequently spread to different continents, sorghum (Sorghum bicolor) is featured with multiple onsets of domestication and intensive breeding selection for various end uses. However, how these processes shaped sorghum genomes are not fully unveiled. In the present study, population genomics were performed on a worldwide collection of 445 sorghum accessions, covering wild and four end-use subpopulations with diverse agronomic traits. Frequent genetic exchanges were found amongst various subpopulations, and strong selective sweeps affected 14.68% (∼107.5 Mb) of the sorghum genome, including 3649, 4287, and 3888 genes during domestication, improvement of grain and sweet sorghum, respectively. Eight different models of haplotype changes in the domestication genes from wild to landrace and improved sorghum were observed, and Sh1- and SbTB1-type genes represented two prominent models, the one of soft selection or multiple origins and the one of hard selection or early single domestication event, respectively. We also demonstrated that Dry gene, regulating stem juiciness, was unconsciously selected during grain sorghum improvement. Together, this study will facilitate further dissection of the domestication process and molecular breeding of sorghum.