Contributed by Eviatar Nevo, September 11, 2012 (sent for review August 12, 2012)
The Near East Fertile Crescent is well recognized as a primary center of barley origin, diversity, and domestication. A large number of wild barleys have been collected from the Tibetan Plateau, which is characterized by an extreme environment. We used genome-wide diversity array technology markers to analyze the genotypic division between wild barley from the Near East and Tibet. Our results confirmed the existence of Tibetan wild barley and suggested that the split between the wild barleys in the Near East and those in Tibet occurred around 2.76 million years ago (Mya). To test the concept of polyphyletic domestication of barley, we characterized a set of worldwide cultivated barley. Some Chinese hulless and six-rowed barleys showed a close relationship with Tibetan wild barley but showed no common ancestor with other cultivated barley. Our data support the concept of polyphyletic domestication of cultivated barley and indicate that the Tibetan Plateau and its vicinity is one of the centers of domestication of cultivated barley. The current results may be highly significant in exploring the elite germplasm for barley breeding, especially against cold and drought stresses.
Author contributions: F.D., E.N., and G.Z. designed research; F.D., D.W., J.C., and L.Q. performed research; A.B. and G.C. contributed new reagents/analytic tools; F.D., D.W., J.C., M.Z., and Z.C. analyzed data; and F.D., E.N., M.Z., Z.C., and G.Z. wrote the paper.
The authors declare no conflict of interest.
Data deposition: The sequences reported in this paper have been deposited in the GenBank database (accession nos. JX271894, JX271895, JX271896, and JX271897).
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1215265109/-/DCSupplemental.
Freely available online through the PNAS open access option.
