Wheat is a grass widely cultivated for its seed, a cereal grain which is a worldwide staple food. The many species of wheat together make up the genus Triticum; the most widely grown is common wheat (T. aestivum).
Wheat is grown on more land area than any other food crop (220.4 million hectares, 2014). World trade in wheat is greater than for all other crops combined. In 2016, world production of wheat was 749 million tonnes, making it the second most-produced cereal after maize. Since 1960, world production of wheat and other grain crops has tripled and is expected to grow further through the middle of the 21st century. Global demand for wheat is increasing due to the unique viscoelastic and adhesive properties of gluten proteins, which facilitate the production of processed foods, whose consumption is increasing as a result of the worldwide industrialization process and the westernization of the diet.
Wheat is an important source of carbohydrates. Globally, it is the leading source of vegetal protein in human food, having a protein content of about 13%, which is relatively high compared to other major cereals  but relatively low in protein quality for supplying essential amino acids. When eaten as the whole grain, wheat is a source of multiple nutrients and dietary fiber.
Cultivation and repeated harvesting and sowing of the grains of wild grasses led to the creation of domestic strains, as mutant forms ('sports') of wheat were preferentially chosen by farmers. 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. Selection for these traits by farmers might not have been deliberately intended, but simply have occurred because these traits made gathering the seeds easier; nevertheless such 'incidental' selection was an important part of crop domestication. As the traits that improve wheat as a food source also involve the loss of the plant's natural seed dispersal mechanisms, highly domesticated strains of wheat cannot survive in the wild.
Cultivation of wheat began to spread beyond the Fertile Crescent after about 8000 BCE. Jared Diamond traces the spread of cultivated emmer wheat starting in the Fertile Crescent sometime before 8800 BCE. Archaeological analysis of wild emmer indicates that it was first cultivated in the southern Levant, with finds dating back as far as 9600 BCE. Genetic analysis of wild einkorn wheat suggests that it was first grown in the Karacadag Mountains in southeastern Turkey. 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 anomalous exception of two grains from Iraq ed-Dubb, the earliest carbon-14 date for einkorn wheat remains at Abu Hureyra is 7800 to 7500 years BCE.
Remains of harvested emmer from several sites near the Karacadag Range have been dated to between 8600 (at Cayonu) and 8400 BCE (Abu Hureyra), that is, in the Neolithic period. With the exception of Iraq ed-Dubb, the earliest carbon-14 dated remains of domesticated emmer wheat were found in the earliest levels of Tell Aswad, in the Damascus basin, near Mount Hermon in Syria. These remains were dated by Willem van Zeist and his assistant Johanna Bakker-Heeres to 8800 BCE. 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.
The cultivation of emmer reached Greece, Cyprus and India by 6500 BCE, Egypt shortly after 6000 BCE, and Germany and Spain by 5000 BCE. "The early Egyptians were developers of bread and the use of the oven and developed baking into one of the first large-scale food production industries."  By 3000 BCE, wheat had reached the British Isles and Scandinavia. A millennium later it reached China.
The oldest evidence for hexaploid wheat has been confirmed through DNA analysis of wheat seeds, dating to around 6400-6200 BCE, recovered from Çatalhöyük. The first identifiable bread wheat (Triticum aestivum) with sufficient gluten for yeasted breads has been identified using DNA analysis in samples from a granary dating to approximately 1350 BCE at Assiros in Macedonia.
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 seed 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. Improved agricultural husbandry has more recently included threshing machines and reaping machines (the 'combine harvester'), tractor-drawn cultivators and planters, and better varieties (see Green Revolution and Norin 10 wheat). Great expansion of wheat production occurred as new arable land was farmed in the Americas and Australia in the 19th and 20th centuries.
Leaves emerge from the shoot apical meristem in a telescoping fashion until the transition to reproduction ie. flowering. The last leaf produced by a wheat plant is known as the flag leaf. It is denser and has a higher photosynthetic rate than other leaves, to supply carbohydrate to the developing ear. In temperate countries the flag leaf, along with the second and third highest leaf on the plant, supply the majority of carbohydrate in the grain and their condition is paramount to yield formation. Wheat is unusual among plants in having more stomata on the upper (adaxial) side of the leaf, than on the under (abaxial) side. It has been theorised that this might be an effect of it having been domesticated and cultivated longer than any other plant. Winter wheat generally produces up to 15 leaves per shoot and spring wheat up to 9 and winter crops may have up to 35 tillers (shoots) per plant (depending on cultivar).
Wheat roots are among the deepest of arable crops, extending as far down as 2m. While the roots of a wheat plant are growing, the plant also accumulates an energy store in its stem, in the form of fructans, which helps the plant to yield under drought and disease pressure, but it has been observed that there is a trade-off between root growth and stem non-structural carbohydrate reserves. Root growth is likely to be prioritised in drought-adapted crops, while stem non-structural carbohydrate is prioritised in varieties developed for countries where disease is a bigger issue. Depending on variety, wheat may be awned or not awned. Producing awns incurs a cost in grain number, but wheat awns photosynthesise more water-use-efficiently than their leaves, so awns are much more frequent in varieties of wheat grown in hot drought-prone countries than those generally seen in temperate countries. For this reason, awned varieties could become more widely grown due to climate change. In Europe, however, a decline in climate resilience of wheat has been observed.
Wheat genetics is more complicated than that of most other domesticated species. Some wheat species are diploid, with two sets of chromosomes, but many are stable polyploids, with 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. Genes for the 'dwarfing' trait, first used by Japanese wheat breeders to produce short-stalked wheat, have had a huge effect on wheat yields worldwide, and were major factors in the success of the Green Revolution in Mexico and Asia, an initiative led by Norman Borlaug. Dwarfing genes enable the carbon that is fixed in the plant during photosynthesis to be diverted towards seed production, and they also help prevent the problem of lodging. 'Lodging' occurs when an ear stalk falls over in the wind and rots on the ground, and heavy nitrogenous fertilization of wheat makes the grass grow taller and become more susceptible to this problem. By 1997, 81% of the developing world's wheat area was planted to semi-dwarf wheats, giving both increased yields and better response to nitrogenous fertilizer.
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 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. Hybrid wheat has been a limited commercial success in Europe (particularly France), the United States and South Africa. F1 hybrid wheat cultivars should not be confused with the standard method of breeding inbred wheat cultivars by crossing two lines using hand emasculation, then selfing or inbreeding the progeny many (ten or more) generations before release selections are identified to be released as a variety or cultivar.
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 used for breeding wheat varieties with improved water-use efficiency. These varieties can improve crop productivity in rain-fed dry-land wheat farms.
In 2010, a team of UK scientists funded by BBSRC announced they had decoded the wheat genome for the first time (95% of the genome of a variety of wheat known as Chinese Spring line 42). This genome was released in a basic format for scientists and plant breeders to use but was not a fully annotated sequence which was reported in some of the media.
On 29 November 2012, an essentially complete gene set of bread wheat was published. Random shotgun libraries of total DNA and cDNA from the T. aestivum cv. Chinese Spring (CS42) were sequenced in Roche 454 pyrosequencer using GS FLX Titanium and GS FLX+ platforms to generate 85 Gb of sequence (220 million reads), equivalent to 5X genome coverage and identified between 94,000 and 96,000 genes.
This sequence data provides direct access to about 96,000 genes, relying on orthologous gene sets from other cereals. and represents an essential step towards a systematic understanding of biology and engineering the cereal crop for valuable traits. 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 landraces, informal 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 breeding 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 the 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: eyespot, Stagonospora nodorum blotch (also known as glume blotch), yellow or stripe rust, powdery mildew, Septoria tritici blotch (sometimes known as leaf blotch), brown or leaf rust, Fusarium head blight, tan spot and stem rust. In tropical areas, spot blotch (also known as Helminthosporium leaf blight) is also important.
Wheat has also been the subject of mutation breeding, with the use of gamma, x-rays, ultraviolet light, and sometimes harsh chemicals. The varieties of wheat created through these methods are in the hundreds (going as far back as 1960), more of them being created in higher populated countries such as China. Bread wheat with high grain iron and zinc content was developed through gamma radiation breeding. Modern bread wheat varieties have been cross-bred to contain greater amounts of gluten, which affords significant advantages for improving the quality of breads and pastas from a functional point of view. Gluten is appreciated for its unique viscoelastic properties. It gives elasticity to dough and is responsible for dough's gas-retaining properties.
International wheat breeding is led by CIMMYT in Mexico. ICARDA is another major public sector international wheat breeder, but it was forced to relocate from Syria in the Syrian Civil War. The world record wheat yield is about 17t/ha, reached in New Zealand in 2017. A project in the UK, led by Rothamsted Research has aimed to raise wheat yields in the country to 20t/ha by 2020, but in 2018 the UK record stood at 16t/ha, and the average yield was just 8t/ha.
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. F1 hybrid wheat cultivars should not be confused with wheat cultivars deriving from standard plant breeding. 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, meaning they have both male and female parts, and normally self-pollinate. Commercial hybrid wheat seed has been produced using chemical hybridizing agents, plant growth regulators that selectively interfere with pollen development, or naturally occurring cytoplasmic male sterility systems. Hybrid wheat has been a limited commercial success in Europe (particularly France), the United States and South Africa.
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, discussed in a separate article on wheat taxonomy. The name of a wheat species from one information 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 more or less the same in Canada as in the US, as broadly the same commercial cash crop strains can be found in both.
Red wheats may need bleaching; therefore, white wheats usually command higher prices than red wheats on the commodities market.
|Wheat, hard red winter|
|Nutritional value per 100 g (3.5 oz)|
|Energy||1,368 kJ (327 kcal)|
|Dietary fiber||12.2 g|
|Pantothenic acid (B5)|
|†Percentages are roughly approximated using US recommendations for adults. |
Source: USDA Nutrient Database
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 steamed), dried, 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 outer husk or bran can be used several ways.
Wheat is a major ingredient in such foods as bread, porridge, crackers, biscuits, Muesli, pancakes, pasta and noodles, pies, pastries, pizza, polenta and semolina, cakes, cookies, muffins, rolls, doughnuts, gravy, beer, vodka, boza (a fermented beverage), and breakfast cereals.
In manufacturing wheat products, gluten is 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.
In 100 grams, wheat provides 327 kilocalories and is a rich source (20% or more of the Daily Value, DV) of multiple essential nutrients, such as protein, dietary fiber, manganese, phosphorus and niacin (table). Several B vitamins and other dietary minerals are in significant content. Wheat is 13% water, 71% carbohydrates, and 1.5% fat. Its 13% protein content is mostly gluten (75-80% of the protein in wheat).
Wheat proteins have a low quality for human nutrition, according to the new protein quality method (DIAAS) promoted by the Food and Agriculture Organization. Though they contain adequate amounts of the other essential amino acids, at least for adults, wheat proteins are deficient in the essential amino acid, lysine. Because the proteins present in the wheat endosperm (gluten proteins) are particularly poor in lysine, white flours are more deficient in lysine compared with whole grains. Significant efforts in plant breeding are being made to develop lysine-rich wheat varieties, without success as of 2017. Supplementation with proteins from other food sources (mainly legumes) is commonly used to compensate for this deficiency, since the limitation of a single essential amino acid causes the others to break down and become excreted, which is especially important during the period of growth.
|cooking Reduction %||10||30||20||25||25||35||0||0||30||10||15||20||10||20||5||10||25|
|%DV = % daily value i.e. % of DRI (Dietary Reference Intake)
Note: All nutrient values including protein and fiber are in %DV per 100 grams of the food item. Significant values are highlighted in light Gray color and bold letters.  Cooking reduction = % Maximum typical reduction in nutrients due to boiling without draining for ovo-lacto-vegetables group Q = Quality of Protein in terms of completeness without adjusting for digestability.
100 g (3.5 oz) of hard red winter wheat contain about 12.6 g (0.44 oz) of protein, 1.5 g (0.053 oz) of total fat, 71 g (2.5 oz) of carbohydrate (by difference), 12.2 g (0.43 oz) of dietary fiber, and 3.2 mg (0.00011 oz) of iron (17% of the daily requirement); the same weight of hard red spring wheat contains about 15.4 g (0.54 oz) of protein, 1.9 g (0.067 oz) of total fat, 68 g (2.4 oz) of carbohydrate (by difference), 12.2 g (0.43 oz) of dietary fiber, and 3.6 mg (0.00013 oz) of iron (20% of the daily requirement).
Wheat is grown on more than 218,000,000 hectares (540,000,000 acres), a larger area than for any other crop. World trade in wheat is greater than for all other crops combined. With rice, wheat is the world's most favored staple food. It is a major diet component because of the wheat plant's agronomic adaptability with the ability to grow from near arctic regions to equator, from sea level to plains of Tibet, approximately 4,000 m (13,000 ft) above sea level. In addition to agronomic adaptability, 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 forms 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, 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. When eaten as the whole grain, wheat is a healthy food source of multiple nutrients and dietary fiber recommended for children and adults, in several daily servings containing a variety of foods that meet whole grain-rich criteria. Dietary fiber may also help people feel full and therefore help with a healthy weight. Further, wheat is a major source for natural and biofortified nutrient supplementation, including dietary fiber, protein and dietary minerals.
Manufacturers of foods containing wheat as a whole grain in specified amounts are allowed a health claim for marketing purposes in the United States, stating: "low fat diets rich in fiber-containing grain products, fruits, and vegetables may reduce the risk of some types of cancer, a disease associated with many factors" and "diets low in saturated fat and cholesterol and rich in fruits, vegetables, and grain products that contain some types of dietary fiber, particularly soluble fiber, may reduce the risk of heart disease, a disease associated with many factors". The scientific opinion of the European Food Safety Authority (EFSA) related to health claims on gut health/bowel function, weight control, blood glucose/insulin levels, weight management, blood cholesterol, satiety, glycaemic index, digestive function and cardiovascular health is "that the food constituent, whole grain, (...) is not sufficiently characterised in relation to the claimed health effects" and "that a cause and effect relationship cannot be established between the consumption of whole grain and the claimed effects considered in this opinion."
In genetically susceptible people, gluten – a major part of wheat protein – can trigger coeliac disease. Coeliac disease affects about 1% of the general population in developed countries. There is evidence that most cases remain undiagnosed and untreated. The only known effective treatment is a strict lifelong gluten-free diet.
While coeliac disease is caused by a reaction to wheat proteins, it is not the same as a wheat allergy. Other diseases triggered by eating gluten are non-coeliac gluten sensitivity (estimated to affect 0.5% to 13% of the general population), gluten ataxia and dermatitis herpetiformis.
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: baking, boiling, steaming, frying, etc.).
|Nutrient||Maize (corn)[A]||Rice, white[B]||Wheat[C]||Potatoes[D]||Cassava[E]||Soybeans, green[F]||Sweet potatoes[G]||Yams[Y]||Sorghum[H]||Plantain[Z]||RDA|
|Vitamin C (mg)||0||0||0||19.7||20.6||29||2.4||17.1||0||18.4||90|
|Thiamin (B1) (mg)||0.39||0.07||0.30||0.08||0.09||0.44||0.08||0.11||0.24||0.05||1.2|
|Riboflavin (B2) (mg)||0.20||0.05||0.12||0.03||0.05||0.18||0.06||0.03||0.14||0.05||1.3|
|Niacin (B3) (mg)||3.63||1.6||5.46||1.05||0.85||1.65||0.56||0.55||2.93||0.69||16|
|Pantothenic acid (B5) (mg)||0.42||1.01||0.95||0.30||0.11||0.15||0.80||0.31||-||0.26||5|
|Vitamin B6 (mg)||0.62||0.16||0.3||0.30||0.09||0.07||0.21||0.29||-||0.30||1.3|
|Folate Total (B9) (μg)||19||8||38||16||27||165||11||23||0||22||400|
|Vitamin A (IU)||214||0||9||2||13||180||14,187||138||0||1,127||5,000|
|Vitamin E, alpha-tocopherol (mg)||0.49||0.11||1.01||0.01||0.19||0||0.26||0.39||0||0.14||15|
|Vitamin K1 (μg)||0.3||0.1||1.9||1.9||1.9||0||1.8||2.6||0||0.7||120|
|Saturated fatty acids (g)||0.67||0.18||0.26||0.03||0.07||0.79||0.02||0.04||0.46||0.14||minimal|
|Monounsaturated fatty acids (g)||1.25||0.21||0.2||0.00||0.08||1.28||0.00||0.01||0.99||0.03||22–55|
|Polyunsaturated fatty acids (g)||2.16||0.18||0.63||0.04||0.05||3.20||0.01||0.08||1.37||0.07||13–19|
|A raw yellow dent corn||B raw unenriched long-grain white rice|
|C raw hard red winter wheat||D raw potato with flesh and skin|
|E raw cassava||F raw green soybeans|
|G raw sweet potato||H raw sorghum|
|Y raw yam||Z raw plantains|
Harvested wheat grain that enters trade is 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 because it produces a good yield per unit area, grows well in a temperate climate even with a moderately short growing season, and yields a versatile, high-quality flour that is widely used in baking. Most breads are made with wheat flour, including many breads named for the other grains they contain, for example, most rye and oat breads. The popularity of 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. In 1998, the price at harvest of a 60 pounds (27 kg) bushel was $2.68 per. Some information providers, following CBOT practice, quote the wheat market in per ton denomination. A USDA report revealed that in 1998, average operating costs were $1.43 per bushel and total costs were $3.97 per bushel. In that study, farm wheat yields averaged 41.7 bushels per acre (2.2435 metric ton/hectare), and typical total wheat production value was $31,900 per farm, with total farm production value (including other crops) of $173,681 per farm, plus $17,402 in government payments. There were significant profitability differences between low- and high-cost farms, mainly due to crop yield differences, location, and farm size.
In 2016, global wheat production was 749 million tonnes. Wheat is the primary food staple in North Africa and the Middle East, and is growing in uses in Asia. Unlike rice, wheat production is more widespread globally, though 47% of the world total in 2014 was produced by just four countries – China, India, Russia and the United States (table).
In the 20th century, global wheat output expanded by about 5-fold, but until about 1955 most of this reflected increases in wheat crop area, with lesser (about 20%) increases in crop yields per unit area. After 1955 however, there was a ten-fold increase in the rate of wheat yield improvement per year, and this became the major factor allowing global wheat production to increase. Thus technological innovation and scientific crop management with synthetic nitrogen fertilizer, irrigation 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, for instance in North America.
Better seed storage and germination ability (and hence a smaller requirement to retain harvested crop for next year's seed) is another 20th-century technological innovation. In Medieval England, farmers saved one-quarter of their wheat harvest as seed for the next crop, leaving only three-quarters for food and feed consumption. By 1999, the global average seed use of wheat was about 6% of output.
Several factors are currently slowing the rate of global expansion of wheat production: population growth rates are falling while wheat yields continue to rise, and the better economic profitability of other crops such as soybeans and maize, linked with investment in modern genetic technologies, has promoted shifts to other crops.
In 2014, the most productive crop yields for wheat were in Ireland, producing 10 tonnes per hectare. In addition to gaps in farming system technology and knowledge, some large wheat grain-producing countries have significant losses after harvest at the farm and because of poor roads, inadequate storage technologies, inefficient supply chains and farmers' inability to bring the produce into retail markets dominated by small shopkeepers. Various studies in India, for example, have concluded that about 10% of total wheat production is lost at farm level, another 10% is lost because of poor storage and road networks, and additional amounts lost at the retail level.
In the Punjab region of India and Pakistan, as well as North China, irrigation has been a major contributor to increased grain output. More widely over the last 40 years, a massive increase in fertilizer use together with the increased availability of semi-dwarf varieties in developing countries, has greatly increased yields per hectare. In developing countries, use of (mainly nitrogenous) fertilizer increased 25-fold in this period. However, farming systems rely on much more than fertilizer and breeding to improve productivity. A good illustration of this is Australian wheat growing in the southern winter cropping zone, where, despite low rainfall (300 mm), wheat cropping is successful even with relatively little use of nitrogenous fertilizer. This is achieved by 'rotation cropping' (traditionally called the ley system) with leguminous pastures and, in the last decade, including a canola crop in the rotations has boosted wheat yields by a further 25%. In these low rainfall areas, better use of available soil-water (and better control of soil erosion) is achieved by retaining the stubble after harvesting and by minimizing tillage.
|Country||millions of tonnes|
There are substantial differences in wheat farming, trading, policy, sector growth, and wheat uses in different regions of the world. The largest exporters of wheat in 2013 were, in order of exported quantities: United States (33.2 million tonnes), Canada (19.8 million tonnes), France (19.6 million tonnes), Australia (18 million tonnes), and the Russian Federation (13.8 million tonnes). The largest importers of wheat in 2013 were, in order of imported quantities: Egypt (10.3 million tonnes), Brazil (7.3 million tonnes), Indonesia (6.7 million tonnes), Algeria (6.3 million tonnes) and Japan (6.2 million tonnes).
In the rapidly developing countries of Asia and Africa, westernization of diets associated with increasing prosperity is leading to growth in per capita demand for wheat at the expense of the other food staples.
In the past, there has been significant governmental intervention in wheat markets, such as price supports in the US and farm payments in the EU. In the EU, these subsidies have encouraged heavy use of fertilizer inputs with resulting high crop yields. In Australia and Argentina, direct government subsidies are much lower.
The average annual world farm yield for wheat in 2014 was 3.3 tonnes per hectare (330 grams per square meter). Ireland wheat farms were the most productive in 2014, with a nationwide average of 10.0 tonnes per hectare, followed by the Netherlands (9.2), and Germany, New Zealand and the United Kingdom (each with 8.6).
Wheat futures are traded on the Chicago Board of Trade, Kansas City Board of Trade, and Minneapolis Grain Exchange, and have delivery dates in March (H), May (K), July (N), September (U), and December (Z).
Wheat normally needs between 110 and 130 days between sowing and harvest, depending upon climate, seed type, and soil conditions (winter wheat lies dormant during a winter freeze). Optimal crop management requires that the farmer have a detailed understanding of each stage of development in the growing plants. In particular, spring fertilizers, herbicides, fungicides, and growth regulators are typically applied only at specific stages of plant development. For example, it is currently recommended that the second application of nitrogen is best done when the ear (not visible at this stage) is about 1 cm in size (Z31 on Zadoks scale). Knowledge of stages is also important to identify periods of higher risk from the climate. For example, pollen formation from the mother cell, and the stages between anthesis and maturity are susceptible to high temperatures, and this adverse effect is made worse by water stress. Farmers also benefit from knowing when the 'flag leaf' (last leaf) appears, as this leaf represents about 75% of photosynthesis reactions during the grain filling period, and so should be preserved from disease or insect attacks to ensure a good yield.
Several systems exist to identify crop stages, with the Feekes and Zadoks scales being the most widely used. Each scale is a standard system which describes successive stages reached by the crop during the agricultural season.
Wheat at the anthesis stage. Face view (left) and side view (right) and wheat ear at the late milk
There are many wheat diseases, mainly caused by fungi, bacteria, and viruses. Plant breeding to develop new disease-resistant varieties, and sound crop management practices are important for preventing disease. Fungicides, used to prevent the significant crop losses from fungal disease, can be a significant variable cost in wheat production. Estimates of the amount of wheat production lost owing to plant diseases vary between 10–25% in Missouri. A wide range of organisms infect wheat, of which the most important are viruses and fungi.
The main wheat-disease categories are:
Wheat is used as a food plant by the larvae of some Lepidoptera (butterfly and moth) species including the flame, rustic shoulder-knot, setaceous Hebrew character and turnip moth. Early in the season, many species of birds, including the long-tailed widowbird, and rodents feed upon wheat crops. These animals can cause significant damage to a crop by digging up and eating newly planted seeds or young plants. They can also damage the crop late in the season by eating the grain from the mature spike. Recent post-harvest losses in cereals amount to billions of dollars per year in the United States alone, and damage to wheat by various borers, beetles and weevils is no exception. Rodents can also cause major losses during storage, and in major grain growing regions, field mice numbers can sometimes build up explosively to plague proportions because of the ready availability of food. To reduce the amount of wheat lost to post-harvest pests, Agricultural Research Service scientists have developed an "insect-o-graph," which can detect insects in wheat that are not visible to the naked eye. The device uses electrical signals to detect the insects as the wheat is being milled. The new technology is so precise that it can detect 5–10 infested seeds out of 300,000 good ones. Tracking insect infestations in stored grain is critical for food safety as well as for the marketing value of the crop.
Perhaps the simplest of fruits are those of grasses (all cereals such as corn and wheat)...These fruits are caryopses.
When compared with the WHO requirements of essential amino acids for humans, wheat, barley and rye are seen to be deficient in lysine, with threonine being the second limiting amino acid (Table 1).
Additionally, menu planners are encouraged to serve a variety of foods that meet whole grain-rich criteria and may not serve the same product every day to count for the HUSSC whole grain-rich criteria.
Bran, also known as miller's bran, is the hard outer layers of cereal grain. It consists of the combined aleurone and pericarp. Along with germ, it is an integral part of whole grains, and is often produced as a byproduct of milling in the production of refined grains.
Bran is present in cereal grain, including rice, corn (maize), wheat, oats, barley, rye and millet. Bran is not the same as chaff, which is a coarser scaly material surrounding the grain but not forming part of the grain itself.Brandon Wheat Kings
The Brandon Wheat Kings are a Canadian junior ice hockey team based in Brandon, Manitoba. They are members of the Western Hockey League, joining the league in the 1967–68 season. Prior to that they played in the Manitoba Junior Hockey League except for two seasons in the mid-1960s when they played in the Saskatchewan Junior Hockey League. The team was known as the Brandon Elks for a short time in the late 1930s. They won 8 Turnbull Cup Championships as Manitoba Junior Champions, 1939, 1947, 1949, 1950, 1960, 1962, 1963, & 1964 and appeared in the Memorial Cup six times: in 1949 (as an MJHL team), 1979, 1995, 1996, 2010, and 2016, losing each time. The team plays its home games at the Keystone Centre. They also played at Wheat City Arena until 1969, and the Manex Arena from 1969 to 1972. Between 1973 and 1980, the Wheat Kings owned and operated a farm team in the MJHL, called the Travellers. The Wheat Kings are currently the only Western Hockey League franchise based in the province of Manitoba.
An earlier incarnation of the Wheat Kings played for the Stanley Cup in 1904, but lost to the Ottawa Senators.
The 1949 Brandon Wheat Kings won the Abbott Cup defeating the Calgary Buffaloes. They went on to lose the Memorial Cup to the Montreal Royals. The 1949 Brandon Wheat Kings were inducted into the Manitoba Hockey Hall of Fame in the team category.
The Wheat Kings hold the CHL record for most points (125) in a single season, setting the mark in 1978–79.
The Western Hockey League announced on October 16, 2008, that the Wheat Kings had been chosen to host the 2010 Memorial Cup championship at the Keystone Centre. They reached the final game, losing to the Windsor Spitfires.
The Brandon Wheat Kings mascot is Willie, a coyote.Bread
Bread is a staple food prepared from a dough of flour and water, usually by baking. Throughout recorded history it has been a prominent food in large parts of the world and is one of the oldest man-made foods, having been of significant importance since the dawn of agriculture.
Bread may be leavened by processes such as reliance on naturally occurring sourdough microbes, chemicals, industrially produced yeast, or high-pressure aeration. Commercial bread commonly contains additives to improve flavor, texture, color, shelf life, nutrition, and ease of manufacturing.
Bread plays essential roles in religious rituals and secular culture.Bulgur
Bulgur (from Turkish: bulgur; also burghul, from Arabic: برغل bourghoul, "groats") is a cereal food made from the cracked parboiled groats of several different wheat species, most often from durum wheat. It originates in Middle Eastern cuisine.Cereal
A cereal is any of the edible components of the grain (botanically, a type of fruit, called a caryopsis) of cultivated grass, composed of the endosperm, germ, and bran. Cereal grains are grown in greater quantities and provide more food energy worldwide than any other type of crop and are therefore staple crops. Edible grains from other plant families, such as buckwheat (Polygonaceae), quinoa (Amaranthaceae) and chia (Lamiaceae), are referred to as pseudocereals.
In their natural, unprocessed, whole grain form, cereals are a rich source of vitamins, minerals, carbohydrates, fats, oils, and protein. When processed by the removal of the bran, and germ, the remaining endosperm is mostly carbohydrate. In some developing countries, grain in the form of rice, wheat, millet, or maize constitutes a majority of daily sustenance. In developed countries, cereal consumption is moderate and varied but still substantial.
The word cereal is derived from Ceres, the Roman goddess of harvest and agriculture.Couscous
Couscous (Arabic: كُسْكُس kuskus) is a Maghrebi dish of small (about 3 millimetres (0.12 in) diameter) steamed balls of crushed durum wheat semolina that is traditionally served with a stew spooned on top. Pearl millet and sorghum especially in the Sahel and other cereals can be cooked in a similar way and the resulting dishes are also sometimes called couscous.Couscous is a staple food throughout the North African cuisines of Algeria, Morocco, Tunisia, Mauritania, Libya, and Egypt. In Western supermarkets, it is sometimes sold in instant form with a flavor packet, and may be served as a side or on its own as a main dish.Durum
Durum wheat (), also called pasta wheat or macaroni wheat (Triticum durum or Triticum turgidum subsp. durum), 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 (with bristles). It is the predominant wheat that grows in the Middle East.
Durum in Latin means "hard", and the species is the hardest of all wheats. This refers to the resistance of the grain to milling, in particular of the starchy endosperm, implying dough made from its flour is weak or "soft". This makes durum favorable for semolina and pasta and less practical for flour, which requires more work than with hexaploid wheats like common bread wheats. Despite its high protein content, durum is not a strong wheat in the sense of giving strength to dough through the formation of a gluten network. Durum contains 27% extractable wet gluten, about 3% higher than in common wheat (T. aestivum L.).Flour
Flour is a powder made by grinding raw grains or roots and used to make many different foods. Cereal flour is the main ingredient of bread, which is a staple food for most cultures. Wheat flour is one of the most important ingredients in Oceanic, European, South American, North American, Middle Eastern, North Indian and North African cultures, and is the defining ingredient in their styles of breads and pastries.
Wheat is the most common base for flour. Corn flour has been important in Mesoamerican cuisine since ancient times and remains a staple in the Americas. Rye flour is a constituent of bread in central Europe.
Cereal flour consists either of the endosperm, germ, and bran together (whole-grain flour) or of the endosperm alone (refined flour). Meal is either differentiable from flour as having slightly coarser particle size (degree of comminution) or is synonymous with flour; the word is used both ways. For example, the word cornmeal often connotes a grittier texture whereas corn flour connotes fine powder, although there is no codified dividing line.Gluten
Gluten (from Latin gluten, "glue") is a composite of storage proteins termed prolamins and glutelins that is stored together with starch in the endosperm (which nourishes the embryonic plant during germination) of various cereal (grass) grains. It is found in wheat, barley, rye, oats and related species and hybrids (such as spelt, khorasan, emmer, einkorn, triticale, etc.), as well as products derived from these grains (such as breads and malts). Glutens, and most especially the Triticeae glutens, are appreciated for their viscoelastic properties, which give dough its elasticity, helping it rise and keep its shape and often leaving the final product with a chewy texture.
Wheat, barley, rye and oat prolamins are respectively known as gliadins, hordeins, secalins and avenins; these protein classes are often collectively referred to as gluten. Wheat glutelins are called glutenin. True gluten is limited to the grains listed above. The storage proteins in maize and rice are sometimes called glutens, but they differ from true gluten.
In a small part of the general human population, gluten can trigger adverse autoimmune reactions responsible for a broad spectrum of gluten-related disorders, including coeliac disease, non-coeliac gluten sensitivity, gluten ataxia and dermatitis herpetiformis. Their treatment is the gluten-free diet. The occurrence of oat avenin toxicity depends on the oat cultivar consumed, because the immunoreactivities of toxic prolamins are different among oat varieties. Also, many oat products are cross-contaminated with other gluten-containing cereals.Green Revolution
The Green Revolution, or Third Agricultural Revolution, is a set of research and technology transfer initiatives occurring between 1950 and the late 1960s, that increased agricultural production worldwide, particularly in the developing world, beginning most markedly in the late 1960s. The initiatives resulted in the adoption of new technologies, including high-yielding varieties (HYVs) of cereals, especially dwarf wheats and rices, in association with chemical fertilizers and agro-chemicals, and with controlled water-supply (usually involving irrigation) and new methods of cultivation, including mechanization. All of these together were seen as a 'package of practices' to supersede 'traditional' technology and to be adopted as a whole.Both the Ford Foundation and the Rockefeller Foundation were heavily involved.
One key leader was Norman Borlaug, the "Father of the Green Revolution", who received the Nobel Peace Prize in 1970. He is credited with saving over a billion people from starvation. The basic approach was the development of high-yielding varieties of cereal grains, expansion of irrigation infrastructure, modernization of management techniques, distribution of hybridized seeds, synthetic fertilizers, and pesticides to farmers.
The term "Green Revolution" was first used in a speech on 8 March 1968 by the administrator of the U.S. Agency for International Development (USAID), William S. Gaud, who noted the spread of the new technologies: "These and other developments in the field of agriculture contain the makings of a new revolution. It is not a violent Red Revolution like that of the Soviets, nor is it a White Revolution like that of the Shah of Iran. I call it the Green Revolution."Norman Borlaug
Norman Ernest Borlaug (; March 25, 1914 – September 12, 2009) was an American agronomist and humanitarian who led initiatives worldwide that contributed to the extensive increases in agricultural production termed the Green Revolution. Borlaug was awarded multiple honors for his work, including the Nobel Peace Prize, the Presidential Medal of Freedom and the Congressional Gold Medal.
Borlaug received his B.S. in forestry in 1937 and Ph.D. in plant pathology and genetics from the University of Minnesota in 1942. He took up an agricultural research position in Mexico, where he developed semi-dwarf, high-yield, disease-resistant wheat varieties. During the mid-20th century, Borlaug led the introduction of these high-yielding varieties combined with modern agricultural production techniques to Mexico, Pakistan, and India. As a result, Mexico became a net exporter of wheat by 1963. Between 1965 and 1970, wheat yields nearly doubled in Pakistan and India, greatly improving the food security in those nations.Borlaug was often called "the father of the Green Revolution", and is credited with saving over a billion people worldwide from starvation. According to Jan Douglas, executive assistant to the president of the World Food Prize Foundation, the source of this number is Gregg Easterbrook's 1997 article "Forgotten Benefactor of Humanity." The article states that the "form of agriculture that Borlaug preaches may have prevented a billion deaths." He was awarded the Nobel Peace Prize in 1970 in recognition of his contributions to world peace through increasing food supply.
Later in his life, he helped apply these methods of increasing food production in Asia and Africa.Pasta
Pasta (Italian pronunciation: [ˈpasta]) is a staple food of traditional Italian cuisine, with the first reference dating to 1154 in Sicily. Also commonly used to refer to the variety of dishes made with it, pasta is a type of noodle typically made from an unleavened dough of a durum wheat flour mixed with water or eggs, and formed into sheets or various shapes, then cooked by boiling or baking. Some pastas are made using rice flour or legumes like black beans or lentils in place of wheat flour to yield a different taste and texture, or for those who need to avoid products containing gluten.Pastas may be divided into two broad categories: dried (pasta secca) and fresh (pasta fresca). Most dried pasta is produced commercially via an extrusion process, although it can be produced at home. Fresh pasta is traditionally produced by hand, sometimes with the aid of simple machines. Fresh pastas available in grocery stores are produced commercially by large-scale machines.
Both dried and fresh pastas come in a number of shapes and varieties, with 310 specific forms known by over 1300 documented names. In Italy, the names of specific pasta shapes or types often vary by locale. For example, the pasta form cavatelli is known by 28 different names depending upon the town and region. Common forms of pasta include long and short shapes, tubes, flat shapes or sheets, miniature shapes for soup, those meant to be filled or stuffed, and specialty or decorative shapes.As a category in Italian cuisine, both fresh and dried pastas are classically used in one of three kinds of prepared dishes: as pasta asciutta (or pastasciutta), cooked pasta is plated and served with a complementary side sauce or condiment; a second classification of pasta dishes is pasta in brodo, in which the pasta is part of a soup-type dish. A third category is pasta al forno, in which the pasta is incorporated into a dish that is subsequently baked in the oven. Pasta dishes are generally simple, but individual dishes vary in preparation. Some pasta dishes are served as a small first course or for light lunches, such as pasta salads. Other dishes may be portioned larger and used for dinner. Pasta sauces similarly may vary in taste, color and texture.In terms of nutrition, cooked plain pasta is 31% carbohydrates (mostly starch), 6% protein, and low in fat, with moderate amounts of manganese, but pasta generally has low micronutrient content. Pasta may be enriched or fortified, or made from whole grains.Rye
Rye (Secale cereale) is a grass grown extensively as a grain, a cover crop and a forage crop. It is a member of the wheat tribe (Triticeae) and is closely related to barley (genus Hordeum) and wheat (Triticum). Rye grain is used for flour, bread, beer, crisp bread, some whiskeys, some vodkas, and animal fodder. It can also be eaten whole, either as boiled rye berries or by being rolled, similar to rolled oats.
Rye is a cereal grain and should not be confused with ryegrass, which is used for lawns, pasture, and hay for livestock.Semolina
Semolina is the coarse, purified wheat middlings of durum wheat mainly used in making upma, pasta, and couscous. The word semolina can also refer to sweet dessert made from semolina and milk. The term semolina is also used to designate coarse middlings from other varieties of wheat, and from other grains, such as rice and maize.Spelt
Spelt (Triticum spelta; Triticum dicoccum), also known as dinkel wheat or hulled wheat, is a species of wheat cultivated since approximately 5000 BC.
Spelt was an important staple in parts of Europe from the Bronze Age to medieval times; it now survives as a relict crop in Central Europe and northern Spain, and has also found a new market as a 'health food'. Spelt is sometimes considered a subspecies of the closely related species common wheat (Triticum aestivum), in which case its botanical name is considered to be Triticum aestivum subsp. spelta. It is a hexaploid wheat, which means it has six sets of chromosomes.Wheat Ridge, Colorado
Wheat Ridge is a Home Rule Municipality located in Jefferson County, Colorado, United States. Wheat Ridge is a western suburb of Denver. The Wheat Ridge Municipal Center is approximately 5 miles (8 km) west-northwest of the Colorado State Capitol in Denver. The city had a population of 30,166 as of the 2010 Census.Wheat beer
Wheat beer is a beer, usually top-fermented, which is brewed with a large proportion of wheat relative to the amount of malted barley. The two main varieties are Weissbier and Witbier; minor types include Lambic, Berliner Weisse and Gose.Wheat flour
Wheat flour is a powder made from the grinding of wheat used for human consumption. Wheat varieties are called "soft" or "weak" if gluten content is low, and are called "hard" or "strong" if they have high gluten content. Hard flour, or bread flour, is high in gluten, with 12% to 14% gluten content, and its dough has elastic toughness that holds its shape well once baked. Soft flour is comparatively low in gluten and thus results in a loaf with a finer, crumbly texture. Soft flour is usually divided into cake flour, which is the lowest in gluten, and pastry flour, which has slightly more gluten than cake flour.
In terms of the parts of the grain (the grass fruit) used in flour—the endosperm or protein/starchy part, the germ or protein/fat/vitamin-rich part, and the bran or fiber part—there are three general types of flour. White flour is made from the endosperm only. Brown flour includes some of the grain's germ and bran, while whole grain or wholemeal flour is made from the entire grain, including the bran, endosperm, and germ. Germ flour is made from the endosperm and germ, excluding the bran.Wheat gluten (food)
Wheat gluten is a food made from gluten, the main protein of wheat. It is made by washing wheat flour dough with water until all the starch granules have been removed, leaving the sticky insoluble gluten as an elastic mass which is then cooked before being eaten.Wheat gluten is an alternative to soybean-based foods such as tofu, which are sometimes used as meat substitutes. Some types of wheat gluten have a chewy or stringy texture that resembles meat more than other substitutes. Wheat gluten is often used instead of meat in Asian, vegetarian, Buddhist, and macrobiotic cuisines. Mock duck is a common use for wheat gluten.
Wheat gluten proteins are deficient in lysine, which is an essential amino acid.Wheat gluten first appeared during the 6th century as an ingredient for Chinese noodles. It has historically been popular in the cuisines of China, Japan and other East and Southeast Asian nations. In Asia, it is commonly found on the menus of restaurants catering primarily to Buddhist customers who do not eat meat.