Genome plasticity a key factor in the success of polyploid wheat under domestication

Wheat was domesticated about 10,000 years ago and has since spread worldwide to become one of the major crops. Its adaptability to diverse environments and end uses is surprising given the diversity bottlenecks expected from recent domestication and polyploid speciation events. Wheat compensates for these bottlenecks by capturing part of the genetic diversity of its progenitors and by generating new diversity at a relatively fast pace. Frequent gene deletions and disruptions generated by a fast replacement rate of repetitive sequences are buffered by the polyploid nature of wheat, resulting in subtle dosage effects on which selection can operate. With 620 million tons produced annu-ally worldwide, wheat provides aboutone-fifth of the calories consumed by humans (1). Roughly 95 % of the wheat crop is common wheat, used for making bread, cookies, and pastries, whereas the remaining 5 % is durum wheat, used for making pasta and other semolina products. Einkorn wheat and other hulled wheats, namely emmer and spelt, are today relic crops of minor economic impor