Transcriptome and Metabolite Insights Into Domestication Process of Cultivated Barley in China
Abstract Background Barley is one of the earliest domesticated crops and regarded as one of the founder of Neolithic transition in the Near East Fertile Crescent. Domestication process of cultivated barley (especially east-Asian cultivated barley) has been under debate because of the controversial origin centers of barley, which caused by widely dispersal of wild barley. What’s more, no comprehensive study regarding alteration in metabolism during domestication has been delineated in barley so far. Results Transcriptomic and non-targeted metabolic analyses were performed for two wild barley populations (wild barley of Near East Fertile Crescent (Wb-NE), and wild barley of Tibetan Plateau (Wb-T)), and one cultivated barley population (cultivated barley of China (Cb-C)), the results revealed two stages of the domestication process of Cb-C, first from Wb-NE to Wb-T, and then from Wb-T to Cb-C. The Wb-T played an important intermediate role in the domestication from Wb-NE to Cb-C, and had made more genetic contribution than Wb-NE to Cb-C. Meanwhile, we found continuous gene flow, a large number of selective genes and metabolites during domestication. Divergent metabolites of alkaloids and phenylpropanoids were specific targeted in stages from Wb-NE to Wb-T and from Wb-T to Cb-C, respectively. The key missense SNPs in genes HORVU6Hr1G027650 and HORVU4Hr1G072150 might be related to the divergence of metabolites of alkaloids and phenylpropanoids during domestication. Conclusions Our results revealed that two stages of the domestication process of Cb-C, and distinct sets of metabolites were targeted by selection during the evolution from wild barley of the Near East Fertile Crescent to Tibetan wild barley to cultivated barley of China. Our findings not only provided genetic and metabolic insights into domestication process of barley but also highlighted the power of combining omics data for trait dissection.