Wheat

WHEAT

Wheat (various species of the genus Triticum) is a grass with so many important uses that it is cultivated worldwide. Not only is wheat an important crop today, it may well have influenced human history. Wheat was a key factor enabling the emergence of city-based societies at the start of civilization because it was one of the first crops that could be easily cultivated on a large scale, and had the additional advantage of yielding a harvest that provides long-term storage of food.
Some wheat is planted as a forage crop for livestock, straw made from stems and leaves can be used as bedding for livestock, or as a construction material for roofing thatch. In England, thatch was used for roofing in the bronze age, and was in common use until the late 19th century.

SPECIES OF WHEAT

Major cultivated species of wheat

•    Einkorn – (T. monococcum). A diploid (AA) species with wild and cultivated variants; one of the earliest wheats to be cultivated. Suited to cooler climes, it has survived as a cultivated crop in the Vaucluse region of  France and the southern Alps for use in a local porridge.
Tetraploid wheats are hybrid species that arise by cross fertilizations between two different wild grasses. Their chromosome content is represented as AABB to indicate the sets of chromosomes they contain, A and B being the component genomes:
•    Emmer – (T. dicoccon). A tetraploid (AABB) species, cultivated in ancient times where it grew in warmer climates than einkorn. No longer in common use, except in Europe where it is sold under its Italian name Farro. In Tuscany, Farro is used make a risotto like dish called Farrotto.
•    Durum – (T. durum). The only tetraploid (AABB) form of wheat in wide use today, and the second most widely cultivated wheat species. It has a similar wild tetraploid grass progenitor to emmer, but is more suited to semi-arid regions.
•    Kamut (Egyptian for wheat) or QK-77 – (T. polonicum or T. durum). A trademarked but ancient durum relative, originally from the middle-east, with a large grain size and high protein content. It is grown in small quantities that are extensively marketed in the USA; more suited for pasta than for breadmaking.

Hexaploid wheats arise by hybridization between a tetraploid wheat and a diploid native grass (DD), with chromosome formula AABBDD. They are all high in the protein gluten, which gives a fluffy leavened bread