Origin and evolution of the bread wheat D genome
Emile Cavalet-Giorsa, Andrea González-Muñoz, Naveenkumar Athiyannan, Samuel Holden, Adil Salhi, Catherine Gardener, Jesús Quiroz-Chávez, Samira Rustamova, Ahmed F. Elkot, Mehran Patpour, Awais Rasheed, Long Mao, Evans Lagudah, Sambasivam Periyannan, Amir Sharon, Axel Himmelbach, Jochen C. Reif, Manuela Knauft, Martin Mascher, Nils Stein, Noam Chayut, Sreya Ghosh, Dragan Perović, Alexander Putra, Ana B. Perera, Chia-Yi Hu, Guotai Yu, Hanin Ibrahim Ahmed, Konstanze D. Laquai, Luis F. Rivera, Renjie Chen, Yajun Wang, Xin Gao, Sanzhen Liu, John Raupp, Eric Olson, Jong-Yeol Lee, Parveen Chhuneja, Satinder Kaur, Peng Zhang, Robert Park, Yi Ding, Dengcai Liu, Wanlong Li, Firuza Nasyrova, Jan Dvořák, M. Abbasi, Meng Li, Naveen Kumar, W. Meyer, Willem H. P. Boshoff, Brian J. Steffenson, Oadi Matny, Parva Kumar Sharma, Vijay Tiwari, Surbhi Grewal, Curtis Pozniak, Harmeet Singh Chawla, Jennifer Ens, Luke T. Dunning, J. A. Kolmer, Gerard R. Lazo, Steven S. Xu, Yong Gu, Xianyang Xu, Cristóbal Uauy, Michaël Abrouk, Salim Bougouffa, Gurcharn S. Brar, Brande B. H. Wulff, Simon G. Krattinger
Abstract
Bread wheat (Triticum aestivum) is a globally dominant crop and major source of calories and proteins for the human diet. Compared with its wild ancestors, modern bread wheat shows lower genetic diversity, caused by polyploidisation, domestication and breeding bottlenecks1,2. Wild wheat relatives represent genetic reservoirs, and harbour diversity and beneficial alleles that have not been incorporated into bread wheat. Here we establish and analyse extensive genome resources for Tausch’s goatgrass (Aegilops tauschii), the donor of the bread wheat D genome. Our analysis of 46 Ae. tauschii genomes enabled us to clone a disease resistance gene and perform haplotype analysis across a complex disease resistance locus, allowing us to discern alleles from paralogous gene copies. We also reveal the complex genetic composition and history of the bread wheat D genome, which involves contributions from genetically and geographically discrete Ae. tauschii subpopulations. Together, our results reveal the complex history of the bread wheat D genome and demonstrate the potential of wild relatives in crop improvement. Analysis of 46 newly sequenced or re-sequenced Tausch’s goatgrass (Aegilops tauschii) accessions establishes the origin of the bread wheat (Triticum aestivum) D genome from genetically and geographically discrete Ae. tauschii subpopulations.