Wheat is a grass widely cultivated for its seed, a cereal grain that is a staple food around the world. The many species of wheat together make up the genus Triticum ; the most widely grown is common wheat. The archaeological record suggests that wheat was first cultivated in the regions of the Fertile Crescent around 9600 BC. Botanically, the wheat kernel is a caryopsis, a type of fruit.
The oat, sometimes called the common oat, is a species of cereal grain grown for its seed, which is known by the same name. Oats appear to have been domesticated as a secondary crop, as their seeds resembled those of other cereals closely enough for them to be included by early cultivators. Oats tolerate cold winters less well than cereals such as wheat, barley, and rye, but need less summer heat and more rain, making them important in areas such as Northwest Europe that have cool wet summers. They can tolerate low-nutrient and acid soils. Oats grow thickly and vigorously, allowing them to outcompete many weeds, and compared to other cereals are relatively free from diseases.
Rye is a grass grown extensively as a grain, a cover crop and a forage crop. It is grown principally in an area from Eastern and Northern Europe into Russia. It is much more tolerant of cold weather and poor soil than other cereals, making it useful in those regions; its vigorous growth suppresses weeds and provides abundant forage for animals early in the year. It is a member of the wheat tribe (Triticeae) which includes the cereals wheat and barley. Rye grain is used for bread, beer, rye whiskey, and animal fodder. In Scandinavia, rye was a staple food in the Middle Ages, and rye crispbread remains a popular food in the region. Europe produces around half of the world's rye; relatively little is traded between countries. A wheat-rye hybrid, triticale, combines the qualities of the two parent crops and is produced in large quantities worldwide. In European folklore, the Roggenwolf is a carnivorous corn demon or Feldgeist.
Einkorn wheat is either a wild species of wheat (Triticum) or its domesticated form. The wild form is T. boeoticum, and the domesticated form is T. monococcum. Einkorn is a diploid species of hulled wheat, with tough glumes (husks) that tightly enclose the grains. The cultivated form is similar to the wild, except that the ear stays intact when ripe and the seeds are larger. The domestic form is known as petit épeautre in French, Einkorn in German, "einkorn" or "littlespelt" in English, piccolo farro in Italian and escanda menor in Spanish. The name refers to the fact that each spikelet contains only one grain.
Triticale is a hybrid of wheat (Triticum) and rye (Secale) first bred in laboratories during the late 19th century in Scotland and Germany. Commercially available triticale is almost always a second-generation hybrid, i.e., a cross between two kinds of primary (first-cross) triticales. As a rule, triticale combines the yield potential and grain quality of wheat with the disease and environmental tolerance of rye. Only recently has it been developed into a commercially viable crop. Depending on the cultivar, triticale can more or less resemble either of its parents. It is grown mostly for forage or fodder, although some triticale-based foods can be purchased at health food stores and can be found in some breakfast cereals.
Secale is a genus of the grass tribe Triticeae, which is related to barley (Hordeum) and wheat (Triticum). The genus includes cultivated species such as rye as well as weedy and wild rye species. The best-known species of the genus is the cultivated rye, S. cereale, which is grown as a grain and forage crop. Wild and weedy rye species help provide a huge gene pool that can be used for improvement of the cultivated rye.
Emmer or hulled wheat is an awned type of wheat. It is a tetraploid. The domesticated types are Triticum turgidum subsp. dicoccum and T. t. conv. durum. The wild plant is called T. t. subsp. dicoccoides. The principal difference between the wild and the domestic forms is that the ripened seed head of the wild plant shatters and scatters the seed onto the ground, while in the domesticated emmer, the seed head remains intact, thus making it easier for people to harvest the grain.
Durum wheat, also called pasta wheat or macaroni wheat, is a tetraploid species of wheat. It is the second most cultivated species of wheat after common wheat, although it represents only 5% to 8% of global wheat production. It was developed by artificial selection of the domesticated emmer wheat strains formerly grown in Central Europe and the Near East around 7000 BC, which developed a naked, free-threshing form. Like emmer, durum wheat is awned. It is the predominant wheat that grows in the Middle East.
Spelt, also known as dinkel wheat or hulled wheat, is a species of wheat. It is a relict crop, eaten in Central Europe and northern Spain. It is high in protein and may be considered a health food.
Khorasan wheat or Oriental wheat is a tetraploid wheat species. The grain is twice the size of modern-day wheat, and has a rich, nutty flavor.
Gliadin is a class of proteins present in wheat and several other cereals within the grass genus Triticum. Gliadins, which are a component of gluten, are essential for giving bread the ability to rise properly during baking. Gliadins and glutenins are the two main components of the gluten fraction of the wheat seed. This gluten is found in products such as wheat flour. Gluten is split about evenly between the gliadins and glutenins, although there are variations found in different sources.
Aegilops is a genus of Eurasian and North American plants in the grass family, Poaceae. They are known generally as goatgrasses. Some species are known as invasive weeds in parts of North America.
Common wheat, also known as bread wheat, is a cultivated wheat species. About 95% of wheat produced worldwide is common wheat; it is the most widely grown of all crops and the cereal with the highest monetary yield.
During 10,000 years of cultivation, numerous forms of wheat, many of them hybrids, have developed under a combination of artificial and natural selection. This diversity has led to much confusion in the naming of wheats. Genetic and morphological characteristics of wheat influence its classification; many common and botanical names of wheat are in current use.
Wheat allergy is an allergy to wheat that typically presents itself as a food allergy, but can also be a contact allergy resulting from occupational exposure. Wheat allergy may be immunoglobulin E mediated or not and may involve mast cell response. Wheat allergy is rare. Prevalence in adults was estimated to be 0.21% in a 2012 study in Japan.
Aegilops tauschii, the Tausch's goatgrass or rough-spike hard grass, is an annual grass species. It is native to Crimea, the Caucasus region, western and Central Asia, Afghanistan, Pakistan, the western Himalaya, and parts of China, and has been introduced to other locales, including California.
Gluten is the seed storage protein in mature wheat seeds. It is the sticky substance in bread wheat which allows dough to rise and retain its shape during baking. The same, or very similar, proteins are also found in related grasses within the tribe Triticeae. Seed glutens of some non-Triticeae plants have similar properties, but none can perform on a par with those of the Triticeae taxa, particularly the Triticum species. What distinguishes bread wheat from these other grass seeds is the quantity of these proteins and the level of subcomponents, with bread wheat having the highest protein content and a complex mixture of proteins derived from three grass species.
Anti-gliadin antibodies are produced in response to gliadin, a prolamin found in wheat. In bread wheat it is encoded by three different alleles, AA, BB, and DD. These alleles can produce slightly different gliadins, which can cause the body to produce different antibodies. Some of these antibodies can detect proteins in specific grass taxa such as Triticeae, while others react sporadically with certain species in those taxa, or over many taxonomically defined grass tribes.
Barley, a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains; it was domesticated in the Fertile Crescent around 9000 BC, giving it nonshattering spikelets and making it much easier to harvest. Its use then spread throughout Eurasia by 2000 BC. Barley prefers relatively low temperatures and well-drained soil to grow. It is relatively tolerant of drought and soil salinity but is less winter-hardy than wheat or rye.
Triticum carthlicum Nevski, 1934, the Persian wheat, is a wheat with a tetraploid genome.
