wheat
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wheat,
cereal plant of the genus Triticum of the family Poaceae (grassgrass,any plant of the family Poaceae (formerly Gramineae), an important and widely distributed group of vascular plants, having an extraordinary range of adaptation. Numbering approximately 600 genera and 9,000 species, the grasses form the climax vegetation (see ecology) in
..... Click the link for more information. family), a major food and an important commodity on the world grain market.
Wheat Varieties and Their Uses
The wheat plant is an annual, probably derived from a perennial; the ancestry of and precise distinctions between species are no longer always clear. For its early growth wheat thrives best in cool weather, though plant breeders have developed durum strains that thrive in hot weather. Among the more ancient, and now less frequently cultivated, species are einkorn (T. monococcum), emmer (T. dicoccum), and spelt (T. spelta). Modern wheat varieties are usually classified as winter wheats (fall-planted and unusually winter hardy for grain crops) and spring wheats. Approximately three fourths of the wheat grown in the United States is winter wheat.
Flour from hard wheats (varieties evolved for the most part from T. aestivum) contains a high percentage of glutengluten,
mixture of proteins present in the cereal grains. The long molecules of gluten, insoluble in water, are strong and flexible and form many cross linkages. This gives flour its characteristic chewiness and permits breads and cakes to rise during baking as the gases within
..... Click the link for more information. and is used to make bread and fine cakes. The hardest-kerneled wheat is durum (T. durum); its flour is primarily used in the manufacture of macaroni, spaghetti, and other pasta products. White- and soft-wheat varieties are paler and have starchy kernels; their flour is preferred for piecrust, biscuits, and breakfast foods. Wheat is used in the manufacture of whiskey and beer, and the grain, the bran (the residue from milling), and the vegetative plant parts make valuable livestock feed. Before the introduction of corn into Europe, wheat was the principal source of starch for sizing paper and cloth.
Diseases and Pests
Wheat is susceptible to many pests and diseases, the more destructive including rustrust,
in botany, name for various parasitic fungi of the order Uredinales and for the diseases of plants that they cause. Rusts form reddish patches of spores on the host plant. About 7,000 species are known.
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name for an order of parasitic fungi (Ustilaginales) and the various diseases of plants caused by them. Smuts produce sootlike masses of spores on the host. The spore masses may break up into a dustlike powder readily scattered by wind (loose smuts) or remain more or less
..... Click the link for more information. ), and the Hessian flyHessian fly,
European gall gnat, Phytophaga destructor, so named because it was first observed in America shortly after the Hessian troops landed on Long Island in the American Revolution. It is one of the most destructive pests of wheat, barley, and rye.
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small North American bug, Blissus leucopterus, of the seed bug family. It feeds on small grains, corn, and other grasses, sucking the plant juices and doing much damage to crops, particularly in the Midwest. The adults, about 1/8 in. (3.
..... Click the link for more information. . All wheat-producing countries carry on breeding experiments to improve existing varieties or to obtain new ones with such dominant characteristics as disease resistance, increased hardiness under specific environments, and greater yield.
Wheat Production Today
The great wheat-producing countries of the world are the United States, China, and Russia; extensive wheat growing is carried on also in India, W Europe, Canada, Argentina, and Australia. In the United States the wheat belt covers the Ohio Valley, the prairie states, and E Oregon and Washington; Kansas leads the states in production. Large-scale mechanized farming and continued planting of wheat without regard to crop rotation have exhausted the soil of large areas. High-yield wheat, one of the grains resulting from the Green RevolutionGreen Revolution,
term referring mainly to dramatic increases in cereal-grain yields in many developing countries beginning in the late 1960s, due largely to use of genetically improved varieties. Beginning in the mid-1940s in Mexico researchers led by American Norman E.
..... Click the link for more information. , requires optimal growth conditions, e.g., adequate irrigation and high concentrations of fertilizer.
History
Wheat was one of the first of the grains domesticated by humans (see graingrain,
in agriculture, term referring to the caryopsis, or dry fruit, of a cereal grass. The term is also applied to the seedlike fruits of buckwheat and of certain other plants and is used collectively for any plant that bears such fruits.
..... Click the link for more information. ). Its cultivation began in the Neolithic periodNeolithic period
or New Stone Age.
The term neolithic is used, especially in archaeology and anthropology, to designate a stage of cultural evolution or technological development characterized by the use of stone tools, the existence of settled villages largely
..... Click the link for more information. ; some ancient species of wheat were domesticated by 10,000 years ago in what is now Turkey. A millennium later wheat had spread to the Near East, and it was cultivated in Egypt by 5000 B.C. By way of Iran, wheat reached India around 4000 B.C. and China around 2000 B.C. About 8,000 years ago it arrived in Greece from Turkey, and then spread throughout Europe, reaching Britain around 3000 B.C. The civilizations of W Asia and of the European peoples have been largely based on wheat, while ricerice,
cereal grain (Oryza sativa) of the grass family (Graminae), probably native to the deltas of the great Asian rivers—the Ganges, the Chang (Yangtze), and the Tigris and Euphrates.
..... Click the link for more information. has been more important in E Asia. Since agriculture began, wheat has been the chief source of bread for Europe and the Middle East. It was introduced into Mexico by the Spaniards c.1520 and into Virginia by English colonists early in the 17th cent.
Classification
Wheat is classified in the division MagnoliophytaMagnoliophyta
, division of the plant kingdom consisting of those organisms commonly called the flowering plants, or angiosperms. The angiosperms have leaves, stems, and roots, and vascular, or conducting, tissue (xylem and phloem).
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Bibliography
See publications issued by the U.S. Dept. of Agriculture; P. T. Dondlinger, The Book of Wheat (1908, repr. 1973); L. T. Evans and W. J. Peacock, ed. Wheat Science: Today and Tomorrow (1981).
What does it mean when you dream about wheat?
A symbol of prosperity and nourishment, wheat can also suggest that the dreamer can “separate the wheat from the chaff.”