Genetic Diversity, Evolution and Domestication of Wheat and Barley in the Fertile Crescent

Abstract

About 12,000 years ago, humans began the transition from hunter-gathering to a sedentary, agriculture-based society. From its origins in the Fertile Crescent, farming expanded throughout Europe, Asia and Africa, together with various domesticated plants and animals. Where, how and why agriculture originated is still debated. Progress has been made in understanding plant domestication in the last few years. The approach to understanding cereal domestication that we have taken in recent years has, in the main, involved the following five-pronged strategy: (1) the use of comprehensive germplasm collections covering the whole distribution area for each species and the collection of new germplasm for wild cereals from their primary habitats in nature; (2) the comparison of many wild and domesticated accessions for each species; (3) the identification of the wild progenitor in the wild gene pool and via comparison of genetic similarity across many loci with domesticate descendants; (4) the use of molecular fingerprinting techniques at many loci to compare wild and domesticate cereals; (5) the identification and cloning of genes involved in domestication. That work has provided some insights into the domestication process, insights that, placed in the archaeological context of human history in the Fertile Crescent, provide information about what humans were doing while domestication was taking place. This chapter reviews recent developments in our understanding of wheat and barley domestication history in the Fertile Crescent, events that forged the foundations of our present-day European culture.