Wheat is a grass widely cultivated for its seeda cereal grain which is a worldwide staple food. Botanically, the wheat kernel is a type of fruit called a caryopsis. Wheat is grown on more land area than any other food crop Wheat is an important source of carbohydrates.
In a small part of the general population, gluten — the major part of wheat protein — can trigger coeliac diseasenoncoeliac gluten sensitivitygluten ataxiaspelt and wheat allergy, and dermatitis herpetiformis. In domesticated wheat, grains are larger, and the seeds inside the spikelets remain attached to the ear by a toughened rachis during harvesting. In wild strains, a more fragile rachis allows the ear to easily shatter and disperse the spikelets.
Dated archeological remains of einkorn wheat in settlement sites near this region, including those at Abu Hureyra in Syria, suggest the domestication of einkorn near the Karacadag Mountain Range. With the exception of Iraq ed-Dubb, the earliest carbon dated remains of domesticated emmer wheat were found in the earliest levels of Tell Aswadin the Damascus basin, spelt and wheat allergy, near Mount Hermon in Syria.
They also concluded that the settlers of Tell Aswad did not develop this form of emmer themselves, but brought the domesticated grains with them from an as yet unidentified location elsewhere. A millennium later it reached China. From Asia, wheat continued to spread across Europe.
In the British Isles, wheat straw thatch was used for roofing in the Bronze Age, and was in common use until the late 19th century. Technological advances in soil preparation and seed placement at planting time, use of crop rotation and fertilizers to improve plant growth, and advances in harvesting methods have all combined to promote wheat as a viable crop.
When the use of seed drills replaced broadcasting sowing of spelt and wheat allergy in the 18th century, another great increase in productivity occurred. Yields of pure wheat per unit area increased as methods of crop rotation were applied to long cultivated land, and the use of fertilizers became widespread. Great expansion of wheat production occurred as new arable land was farmed in the Americas and Australia in the 19th and 20th centuries, spelt and wheat allergy.
Wheat genetics is more complicated than that of most other domesticated species. Some wheat species are diploidwith two sets of chromosomesbut many are stable polyploidswith four sets of chromosomes tetraploid or six hexaploid. The presence of certain versions of wheat genes has been important for crop yields. Apart from mutant versions of genes selected in antiquity during domestication, there has been more recent deliberate selection of alleles that affect growth characteristics.
Dwarfing genes enable the spelt and wheat allergy that is fixed in the plant during photosynthesis to be diverted towards seed production, and they also help provigil and pristiq the problem of lodging.
Wild grasses in the genus Triticum and related genera, and grasses such as rye have been a source of many disease-resistance traits for cultivated wheat breeding since the s. Heterosisspelt and wheat allergy, or hybrid vigor as in the familiar F1 hybrids of maizeoccurs in common hexaploid wheat, but it is difficult to produce seed of hybrid cultivars on a commercial scale as is done with maize because wheat flowers are perfect and normally self-pollinate.
Commercial hybrid wheat seed has been produced using chemical hybridizing agents; these chemicals selectively interfere with pollen development, or naturally occurring cytoplasmic male sterility systems, spelt and wheat allergy. Hybrid wheat has been a limited commercial success in Europe particularly Francethe United States and South Africa.
Synthetic hexaploids made by crossing the wild goatgrass wheat ancestor Aegilops tauschii and various durum wheats are now being deployed, and these increase the genetic diversity of cultivated wheats. Stomata or leaf pores are involved in both uptake of carbon dioxide gas from the atmosphere and water vapor losses from the leaf due to water transpiration.
Basic physiological investigation of these gas exchange processes has yielded valuable carbon isotope based methods that are spelt and wheat allergy for breeding wheat varieties with improved water-use efficiency. These varieties can improve crop productivity in rain-fed dry-land wheat farms.
On 29 Novemberan essentially complete gene set of bread wheat was published. This sequence data provides direct access to about 96, genes, relying on orthologous gene sets from other cereals. Its implications in cereal genetics and breeding includes the examination of genome variation, association mapping using natural populations, performing wide crosses and alien introgression, studying the expression and nucleotide polymorphism in transcriptomes, analyzing population genetics and evolutionary biology, and studying the epigenetic modifications.
Moreover, the availability of large-scale genetic markers generated through NGS technology will facilitate trait mapping and make marker-assisted breeding much feasible.
Moreover, the data not only facilitate in deciphering the complex phenomena such as heterosis and epigenetics, it may also enable breeders to predict which fragment of a chromosome is derived from which parent in the progeny line, thereby recognizing crossover events occurring in every progeny line and inserting markers on genetic and physical maps without ambiguity. In due course, this will assist in introducing specific chromosomal segments from one cultivar to another.
Besides, the researchers had identified diverse classes of genes participating in energy production, metabolism and growth that were probably linked with crop yield, which can now be utilized for the development of transgenic wheat.
Thus whole genome sequence of wheat and the availability of thousands of SNPs will inevitably permit the breeders to stride towards identifying novel traits, providing biological knowledge and empowering biodiversity-based breeding. In traditional agricultural systems wheat populations often consist of landracesinformal farmer-maintained populations that often maintain high levels of morphological diversity.
Although landraces of wheat are no longer grown in Europe and North America, they continue to be important elsewhere. The origins of formal wheat breeding lie in the nineteenth century, when single line varieties were created through selection of seed from a single plant noted to have desired properties. Modern wheat spelt and wheat allergy developed in the first years of the twentieth century and was closely linked to the development of Mendelian genetics.
The standard method of breeding inbred wheat cultivars is by crossing two lines using hand emasculation, then selfing or inbreeding the progeny. Selections are identified shown to have spelt and wheat allergy genes responsible for the varietal differences ten or more generations before release as a variety or cultivar.
The major breeding objectives include high grain yield, good quality, disease and insect resistance and tolerance to abiotic stresses, including mineral, moisture and heat tolerance.
The major diseases in temperate environments include the following, arranged in a rough order of their significance from cooler to warmer climates: In tropical areas, spot blotch also known as Helminthosporium leaf blight is also important. Wheat has also been the subject of mutation breedingwith the use of gamma, x-rays, ultraviolet campral revia and antabuse, and sometimes harsh chemicals.
The varieties of wheat created through these methods are in the hundreds spelt and wheat allergy as far back asmore of them being created in higher populated countries such as China. Because wheat self-pollinates, creating hybrid varieties is extremely labor-intensive; the high cost of hybrid wheat seed relative to its moderate benefits have kept farmers from adopting them widely   despite nearly 90 years of effort.
Heterosis or hybrid vigor as in the familiar F1 hybrids of maize occurs in common hexaploid wheat, but it is difficult to produce seed of hybrid cultivars on a commercial scale as is done with maize because wheat flowers are perfect in the botanical sense, spelt and wheat allergy they have both male and female parts, and normally self-pollinate.
The four wild species of wheat, along with the domesticated varieties einkorn emmer  and spelt have hulls. This more primitive morphology in evolutionary terms consists of toughened glumes that tightly enclose the grains, and in domesticated wheats a semi-brittle rachis that breaks easily on threshing. The result is that when threshed, the wheat ear breaks up into spikelets.
To obtain the grain, further processing, such as milling or pounding, is needed to remove the hulls or husks. In contrast, in free-threshing or naked forms such as durum wheat and common wheat, the glumes are fragile and the rachis tough. On threshing, the chaff breaks up, releasing the grains.
Hulled wheats are often stored as spikelets because the toughened glumes give good protection against pests of stored grain.
There are many botanical classification systems used for wheat species, spelt and wheat allergy, discussed spelt and wheat allergy a separate article on wheat taxonomy. The name of a wheat species from one spelt and wheat allergy source may not be the name of a wheat species in another. Within a species, wheat cultivars are further classified by wheat breeders and farmers in terms of:. The named classes of wheat in English are the more or less the same in Canada as the US, as broadly the same commercial cash crop strains can be found in both.
The classes used in the United States are: Red wheats may need bleaching; therefore, white wheats usually command higher prices than red wheats on the commodities market. Raw wheat can be ground into flour or, using hard durum wheat only, can be ground into semolina ; germinated and dried creating malt ; crushed or cut into cracked wheat; parboiled or steameddried, crushed and de-branned into bulgur also known as groats. If the raw wheat is broken into parts at the mill, as is usually done, the spelt and wheat allergy husk or bran can be used several ways.
Wheat is a major ingredient in such foods as breadporridgecrackersbiscuitsMueslipancakespiespastriescakescookiesmuffinsspelt and wheat allergy, rollsdoughnutsgravybeervodkaboza a fermented beverageand breakfast cereals. In manufacturing wheat products, gluten body builders use animal hormones valuable to impart viscoelastic functional qualities in dough enabling the preparation of diverse processed foods such as breads, noodles, and pasta that facilitate wheat consumption.
Several B vitamins and other dietary minerals are in significant content, spelt and wheat allergy. Wheat proteins have a low quality for human nutrition, according to the new protein quality method DIAAS promoted by the Food and Agriculture Organization. Significant values are highlighted in light Gray color and bold letters. Wheat is grown on more than spelt and wheat allergy, hectares , acres a larger area than for any other crop.
World trade in wheat is greater than for all other crops combined. In addition to agronomic adaptability, spelt and wheat allergy, wheat offers ease of grain storage and ease of converting grain into flour for making edible, palatable, interesting and satisfying foods. Wheat is the most important source of carbohydrate in a majority of countries. The most common spelt and wheat allergy of wheat are white and red wheat.
However, other natural forms of wheat exist. Other commercially minor but nutritionally promising species of naturally evolved wheat species include black, spelt and wheat allergy, yellow and blue wheat.
Consumed worldwide by billions of people, wheat is a significant food for human nutrition, particularly in the least developed countries where wheat products are primary foods.
Manufacturers of foods containing wheat as a whole grain in specified amounts are buy anti viral a health claim for marketing purposes in the United States, stating: In genetically susceptible people, gluten — spelt and wheat allergy major part of wheat protein — can trigger coeliac disease. While coeliac spelt and wheat allergy is caused by a reaction to wheat proteins, it is not the same as a wheat allergy. The following table shows the nutrient content of wheat and other major staple foods in a raw form.
Raw forms of these staples, however, are not edible and cannot be digested. These must be sprouted, or prepared and cooked as appropriate for human consumption. In sprouted or cooked form, the relative nutritional and anti-nutritional contents of each of these grains is remarkably different from that of raw form of these grains reported in this table.
In cooked form, the nutrition value for each staple depends on the cooking method for example: Harvested wheat grain that enters trade spelt and wheat allergy classified according to grain properties for the purposes of the commodity markets. Wheat buyers use these to decide which wheat to buy, as each class has special uses, and producers use them to decide which classes of wheat will be most profitable to cultivate.
Wheat is widely cultivated as a cash crop vitamin d and rashes it produces a good yield per unit area, grows well in a temperate climate even with a moderately short growing seasonand yields a versatile, spelt and wheat allergy, high-quality spelt and wheat allergy that is widely used in baking. Most breads are spelt and wheat allergy with wheat flour, including many breads named for the other grains they contain, for example, most rye and oat breads.
The popularity spelt and wheat allergy foods made from wheat flour creates a large demand for the grain, even in economies with significant food surpluses. In recent years, low international wheat prices have often encouraged farmers in the United States to change to more profitable crops. There were significant profitability differences between low- and high-cost farms, mainly due to crop yield differences, location, and farm size.
In spelt and wheat allergy, global wheat production was million tonnes. After however, there was a ten-fold increase in the rate of wheat yield improvement per year, spelt and wheat allergy, and this became the valerian and diabetes factor allowing global wheat production to increase. Thus technological innovation and scientific crop management with synthetic nitrogen fertilizerirrigation and wheat breeding were the main drivers of wheat output growth in the second half of the century.
There were some significant decreases in wheat crop area, spelt and wheat allergy, for instance in North America. In Medieval England, farmers saved one-quarter of their wheat harvest as seed for the next spelt and wheat allergy, leaving only three-quarters for food and feed consumption.