Wheat originated in the Near East. The first wheat species used were Einkorn wheat (Triticum monococcum) and emmer (Triticum doicum). Wheat after barley is the second oldest cereal. The modern wheat originated from crossing with various cereal and wild grass species. The common wheat originated about 8,000 years ago, when emmer was crossed with Tausch’s goatgrass (Aegilops tauschii). Genes from goatgrass contribute to tolerance against cold and diseases, so that both species can grow in so many parts of the world.
All wheat species belong to the genus Triticum. Within this genus, wheat can be subdivided into three groups by the number of chromosomes: Einkorn (diploid wheat) is the oldest wheat with 14 chromosomes. Emmer (tetraploid wheat) has double chromosomes (28). Emmer, hard wheat (Triticum turgidum ssp durum) and Khorasan wheat. Spelt is hexaploidy wheat with 42 chromosomes. The common wheat (Triticum aestivum) belongs into this group.
Because of its adaptability to various climates wheat is the most common cereal crop of the world. It is basic food for more than a third of the world population and forms about 20% of all calories consumed worldwide.
The first findings of naked wheat are about 4,800 years old. Bread was baked from wheat already during the stone age. Since wheat was cultivated since about the middle Stone Age, types of wheat occur from low elevations to marginal elevations in the mountains. Here wheat was used as a special bread cereal especially during festivities.