Triticeae Genomics and Genetics, 2024, Vol.15, No.5, 234-243 http://cropscipublisher.com/index.php/tgg 235 2 Early Domestication of Wheat (Neolithic Era) 2.1 Geographic origins and genetic evolution The domestication of wheat is a pivotal event in human history, marking the transition from foraging to farming. Bread wheat (Triticum aestivum) originated approximately 8 500~9 000 years ago through hybridization between a domesticated tetraploid progenitor and Aegilops tauschii, the diploid donor of the D subgenome (Figure 1). This hybridization likely occurred in the Fertile Crescent, a region known for its rich biodiversity and favorable conditions for early agriculture. The genetic evolution of wheat was significantly influenced by allopolyploidy, which facilitated the acquisition of new traits and enhanced genetic diversity, enabling wheat to adapt to various climates and environments (Levy and Feldman, 2022). Additionally, the B subgenome's origin remains elusive, suggesting the involvement of an unknown or extinct species. Figure 1 Phylogenetic representation of wheat evolution (Adopted from Levy and Feldman, 2022) Image caption: Wheat evolution is shown starting ~7 MYA from a progenitor that gave rise to the (A), (B), and (D) lineages that merged to form bread wheat; The relative timing of the major speciation events is shown in the horizontal axis and described in the boxes above (Adopted from Levy and Feldman, 2022) 2.2 Archaeobotanical and DNA evidence Archaeobotanical evidence from sites such as Gusir Höyük in Southeast Anatolia provides insights into the early domestication processes. This site, dating back to the 12th-late 11th millennia cal BP, shows selective use and management of cereal and legume crop progenitors, indicating a faster pace of wheat domestication than previously hypothesized (Kabukcu et al., 2021; Zhang, 2024). Similarly, microtexture analysis of sickle blades from Dja’de el-Mughara in the northern Levant reveals complex cereal harvesting strategies during the Early PPNB period, suggesting the exploitation of cereal populations at different domestication stages (Pichon et al., 2021). DNA evidence from ancient wheat samples, such as the 3 000-year-old Egyptian emmer wheat genome, further elucidates the domestication and dispersal history of wheat, highlighting genetic similarities with modern domesticated emmer and unique haplotypes absent in contemporary varieties (Scott et al., 2019). 2.3 Environmental and agronomic conditions The environmental and agronomic conditions during the Neolithic era played a crucial role in the domestication of wheat. The Fertile Crescent's diverse ecogeographies provided a conducive environment for the cultivation and
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