Common wheat

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Common wheat (also known as bread wheat) is by far the most important wheat species in cultivation today.

Contents

1 Evolution
2 Recent history
3 Plant breeding
4 Other forms of common wheat
5 References
6 See also

Evolution

Bread wheat is an allohexaploid (an allopolyploid with six sets of chromosomes, two sets from each of three different species). free-threshing wheat closely related to spelt. As with spelt, genes contributed from goatgrass (Aegilops tauschii) give bread wheat greater cold hardiness than most wheats, and it is cultivated throughout the world's temperate regions.

Recent history

Wheat first reached North America with Spanish missions in the 16th century, but North America's role as a major exporter of grain dates from the colonization of the prairies in the 1870s. As grain exports from Russia ceased in the First World War, grain production in Kansas doubled. Worldwide, bread wheat has proved well adapted to modern industrial baking, and has displaced many of the other wheat, barley, and rye species that were once commonly used for bread making, particularly in Europe.

Plant breeding

Modern wheat varieties have short stems, the result of RHt dwarfing genes that reduce the plant's sensitivity to gibberellic acid, a plant hormone that lengthens cells. RHt genes were introduced to modern wheat varieties in the 1960s from Norin 10 cultivars of wheat grown in Japan. Short stems are important because the application of high levels of chemical fertilizers would otherwise cause the stems to grow too high, resulting in lodging (collapse of the stems). Stem heights are also even, important for modern harvesting techniques.

Other forms of common wheat

Ears of compact wheat

Compact wheats (Triticum compactum, but in India T. sphaerococcum) are closely related to common wheat, but have a much more compact ear. Their shorter rachis segments lead to spikelets packed closer together. Compact wheats are often regarded as subspecies rather than species in their own right (thus T. aestivum subsp. compactum).

References

Excellent resource for 20th century plant breeding.
Standard reference for evolution and early history.

{| align="center" class="toccolours" cellspacing="0" |- | bgcolor="#e7e7ff" align="center" style="font-size: 90%" | Wheat resources ([edit]) |- | align="center" style="font-size: 90%" | History: Domestication, Neolithic Revolution, Tell Abu Hureyra, Aaron Aaronsohn |- | align="center" style="font-size: 90%" | Types of wheat: Wheat taxonomy, Common (Bread) wheat, Durum, Einkorn, Emmer, Kamut (QK-77), Norin 10 wheat, Spelt, Winter wheat |- | align="center" style="font-size: 90%" | Agronomy: Wheat diseases, Wheat mildew Trade: Canadian Wheat Board, International Wheat Council, International wheat production statistics |- | align="center" style="font-size: 90%" | Food: Wheat beer, Wheat Thins, Whole grain, Whole wheat flour, Farina (food), Bran, Flour, Gluten, Bread, Matzo, Wheat gluten (food), Complete Wheat Bran Flakes, Shredded wheat, Pasta, Macaroni, Couscous, Coeliac disease Other Uses: Wheat pasting