North American English
North American English (NAmE) encompasses the English language as spoken in both the United States and Canada. Because of their related histories and cultures, plus the similarities between the pronunciations (accents), vocabulary, and grammar ...
, is a tall stout
grass
Poaceae ( ), also called Gramineae ( ), is a large and nearly ubiquitous family (biology), family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos, the grasses of natural grassland and spe ...
that produces
cereal grain
A cereal is a grass cultivated for its edible grain. Cereals are the world's largest crops, and are therefore staple foods. They include rice, wheat, rye, oats, barley, millet, and maize (Corn). Edible grains from other plant families, suc ...
teosinte
''Zea'' is a genus of flowering plants in the Poaceae, grass family. The best-known species is ''Z. mays'' (variously called maize, corn, or Indian corn), one of the most important crops for human societies throughout much of the world. The four ...
. Native Americans planted it alongside
bean
A bean is the seed of some plants in the legume family (Fabaceae) used as a vegetable for human consumption or animal feed. The seeds are often preserved through drying (a ''pulse''), but fresh beans are also sold. Dried beans are traditi ...
polyculture
In agriculture, polyculture is the practice of growing more than one crop species together in the same place at the same time, in contrast to monoculture, which had become the dominant approach in developed countries by 1950. Traditional example ...
inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...
s or tassels which produce
pollen
Pollen is a powdery substance produced by most types of flowers of seed plants for the purpose of sexual reproduction. It consists of pollen grains (highly reduced Gametophyte#Heterospory, microgametophytes), which produce male gametes (sperm ...
, and female inflorescences called
ears
In vertebrates, an ear is the organ that enables hearing and (in mammals) body balance using the vestibular system. In humans, the ear is described as having three parts: the outer ear, the middle ear and the inner ear. The outer ear co ...
. The ears yield grain, known as
kernels
Kernel may refer to:
Computing
* Kernel (operating system), the central component of most operating systems
* Kernel (image processing), a matrix used for image convolution
* Compute kernel, in GPGPU programming
* Kernel method, in machine learnin ...
or seeds. In modern commercial varieties, these are usually yellow or white; other varieties can be of many colors.
Maize relies on humans for its propagation. Since the
Columbian exchange
The Columbian exchange, also known as the Columbian interchange, was the widespread transfer of plants, animals, and diseases between the New World (the Americas) in the Western Hemisphere, and the Old World (Afro-Eurasia) in the Eastern Hemis ...
, it has become a
staple food
A staple food, food staple, or simply staple, is a food that is eaten often and in such quantities that it constitutes a dominant portion of a standard diet for an individual or a population group, supplying a large fraction of energy needs an ...
wheat
Wheat is a group of wild and crop domestication, domesticated Poaceae, grasses of the genus ''Triticum'' (). They are Agriculture, cultivated for their cereal grains, which are staple foods around the world. Well-known Taxonomy of wheat, whe ...
and
rice
Rice is a cereal grain and in its Domestication, domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species ''Oryza sativa'' (Asian rice)—or, much l ...
. Much maize is used for
animal feed
Animal feed is food given to domestic animals, especially livestock, in the course of animal husbandry. There are two basic types: fodder and forage. Used alone, the word ''feed'' more often refers to fodder. Animal feed is an important input ...
, whether as grain or as the whole plant, which can either be baled or made into the more palatable
silage
Silage is fodder made from green foliage crops which have been preserved by fermentation (food), fermentation to the point of souring. It is fed to cattle, sheep and other ruminants. The fermentation and storage process is called ''ensilage'', ' ...
. Sugar-rich varieties called
sweet corn
Sweet corn (''Zea mays'' convar. ''saccharata'' var. ''rugosa''), also called sweetcorn, sugar corn and pole corn, is a variety of maize grown for human consumption with a high sugar content. Sweet corn is the result of a naturally occurring rec ...
are grown for human consumption, while
field corn
Field corn is a North American term for maize (''Zea mays'') grown for livestock fodder (silage and meal), ethanol, cereal, and processed food products. The principal field corn varieties are dent corn, flint corn, flour corn (also known as sof ...
varieties are used for animal feed, for uses such as
cornmeal
Maize meal is a meal (coarse flour) ground from dried maize. It is a common staple food and is ground to coarse, medium, and fine consistencies, but it is not as fine as wheat flour can be.Herbst, Sharon, ''Food Lover's Companion'', Third Editi ...
or
masa
''Masa'' or ''masa de maíz'' (; ) is a dough made from ground nixtamalized maize. It is used for making corn tortillas, '' gorditas'', '' tamales'', '' pupusas'', and many other Latin American dishes.
It is dried and powdered into a flour f ...
,
corn starch
Cornflour, cornstarch, maize starch, or corn starch (American English) is the starch derived from corn (maize) grain. The starch is obtained from the endosperm of the seed, kernel. Corn starch is a common food ingredient, often used to thick ...
,
corn syrup
Corn syrup is a food syrup that is made from the starch of corn/maize and contains varying amounts of sugars: glucose, maltose and higher oligosaccharides, depending on the grade. Corn syrup is used in foods to soften Mouthfeel, texture, add vol ...
, pressing into
corn oil
Corn oil (North American) or maize oil (British) is oil extracted from the germ of corn (maize). Its main use is in cooking, where its high smoke point makes refined corn oil a valuable frying oil. It is also a key ingredient in some margarin ...
, alcoholic beverages like
bourbon whiskey
Bourbon whiskey (; also simply bourbon) is a Aging (food), barrel-aged American whiskey made primarily from corn (maize). The name derives from the Kingdom of France, French House of Bourbon, although the precise source of inspiration is uncerta ...
, and as chemical feedstocks including
ethanol
Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the ps ...
and other
biofuel
Biofuel is a fuel that is produced over a short time span from Biomass (energy), biomass, rather than by the very slow natural processes involved in the formation of fossil fuels such as oil. Biofuel can be produced from plants or from agricu ...
s.
Maize is cultivated throughout the world; a greater weight of maize is produced each year than any other grain. In 2020, world production was 1.1 billion tonnes. It is afflicted by many
pests
PESTS was an anonymous American activist group formed in 1986 to critique racism, tokenism, and exclusion in the art world. PESTS produced newsletters, posters, and other print material highlighting examples of discrimination in gallery represent ...
and
diseases
A disease is a particular abnormal condition that adversely affects the structure or function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical conditions that are asso ...
; two major
insect
Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...
pests,
European corn borer
The European corn borer (''Ostrinia nubilalis''), also known as the European corn worm or European high-flyer, is a moth of the family Crambidae. It is a pest of grain, particularly maize (''Zea mays''). The insect is native to Europe, origina ...
and corn rootworms, have each caused annual losses of a billion dollars in the US. Modern
plant breeding
Plant breeding is the science of changing the traits of plants in order to produce desired characteristics. It is used to improve the quality of plant products for use by humans and animals. The goals of plant breeding are to produce crop varie ...
has greatly increased output and qualities such as nutrition, drought tolerance, and tolerance of pests and diseases. Much maize is now
genetically modified
Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of technologies used to change the genetic makeup of cells, including th ...
.
As a food, maize is used to make a wide variety of dishes including Mexican
tortilla
A tortilla (, ) is a thin, circular unleavened flatbread from Mesoamerica originally made from maize hominy meal, and now also from wheat flour.
The Aztecs and other Nahuatl speakers called tortillas ''tlaxcalli'' (). First made by the indi ...
s and
tamale
A tamale, in Spanish language, Spanish , is a traditional Mesoamerican dish made of ''masa'', a dough made from nixtamalization, nixtamalized maize, corn, which is steaming, steamed in a corn husk or Banana leaf, banana leaves. The wrapping ...
s, Italian
polenta
Polenta (, ) is an Italian cuisine, Italian dish of boiled cornmeal that was historically made from other grains. It may be allowed to cool and solidify into a loaf that can be baked, fried or Grilling, grilled.
The variety of cereal used is ...
, and American
hominy
Hominy is a food item produced from dried maize (corn) kernels that have been treated with an alkali, in a process called nixtamalization ( is the Nahuatl word for "hominy"). "Lye hominy" is a type of hominy made with lye.
History
The process ...
grits
Grits (stylized as GRITS) is an American Christian hip hop group from Nashville, Tennessee. Their name is an acronym, which stands for "Grammatical Revolution In the Spirit". GRITS is made up of Stacey "Coffee" Jones and Teron "Bonafide" Carter ...
. Maize
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
is low in some
essential amino acid
An essential amino acid, or indispensable amino acid, is an amino acid that cannot be synthesized from scratch by the organism fast enough to supply its demand, and must therefore come from the diet. Of the 21 amino acids common to all life forms ...
s, and the
niacin
Nicotinic acid, or niacin, is an organic compound and a vitamer of vitamin B3, an essential human nutrient. It is produced by plants and animals from the amino acid tryptophan.
Nicotinic acid is also a prescription medication. Amounts f ...
Mesoamerica
Mesoamerica is a historical region and cultural area that begins in the southern part of North America and extends to the Pacific coast of Central America, thus comprising the lands of central and southern Mexico, all of Belize, Guatemala, El S ...
, maize was deified as a maize god and depicted in sculptures.
teosinte
''Zea'' is a genus of flowering plants in the Poaceae, grass family. The best-known species is ''Z. mays'' (variously called maize, corn, or Indian corn), one of the most important crops for human societies throughout much of the world. The four ...
ancestor fall off the cob on their own, while those of
domesticated
Domestication is a multi-generational mutualistic relationship in which an animal species, such as humans or leafcutter ants, takes over control and care of another species, such as sheep or fungi, to obtain from them a steady supply of reso ...
maize do not. All maize arose from a single domestication in southern Mexico about 9,000 years ago. The oldest surviving maize types are those of the Mexican highlands. Maize spread from this region to the lowlands and over the Americas along two major paths. The centre of domestication was most likely the
Balsas River
The Balsas River (Spanish Río Balsas, also locally known as the Mezcala River, or Atoyac River) is a major river of south-central Mexico.
The basin flows through the states of Guerrero, México, Morelos, and Puebla. Downstream of Ciudad Alt ...
valley of south-central Mexico. Maize reached highland Ecuador at least 8000 years ago. It reached lower Central America by 7600 years ago, and the valleys of the Colombian
Andes
The Andes ( ), Andes Mountains or Andean Mountain Range (; ) are the List of longest mountain chains on Earth, longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range ...
between 7000 and 6000 years ago.
The earliest maize plants grew a single, small ear per plant. The
Olmec
The Olmecs () or Olmec were an early known major Mesoamerican civilization, flourishing in the modern-day Mexican states of Veracruz and Tabasco from roughly 1200 to 400 Before the Common Era, BCE during Mesoamerica's Mesoamerican chronolog ...
and
Maya
Maya may refer to:
Ethnic groups
* Maya peoples, of southern Mexico and northern Central America
** Maya civilization, the historical civilization of the Maya peoples
** Mayan languages, the languages of the Maya peoples
* Maya (East Africa), a p ...
cultivated maize in numerous varieties throughout
Mesoamerica
Mesoamerica is a historical region and cultural area that begins in the southern part of North America and extends to the Pacific coast of Central America, thus comprising the lands of central and southern Mexico, all of Belize, Guatemala, El S ...
; they cooked, ground and processed it through
nixtamalization
Nixtamalization ( ) is a process for the preparation of maize (corn), or other cereal grain, grain, in which the grain is soaked and cooking, cooked in an alkaline solution, usually limewater (but sometimes aqueous alkali metal carbonates), ...
. By 3000 years ago, maize was central to Olmec culture, including their calendar, language, and myths.
The
Mapuche
The Mapuche ( , ) also known as Araucanians are a group of Indigenous peoples of the Americas, Indigenous inhabitants of south-central Chile and southwestern Argentina, including parts of Patagonia. The collective term refers to a wide-ranging e ...
quinoa
Quinoa (''Chenopodium quinoa''; , from Quechuan languages, Quechua ' or ') is a flowering plant in the Amaranthaceae, amaranth family. It is a herbaceous annual plant grown as a crop primarily for its edible seeds; the seeds are high in prote ...
and
potatoes
The potato () is a starchy tuberous vegetable native to the Americas that is consumed as a staple food in many parts of the world. Potatoes are underground stem tubers of the plant ''Solanum tuberosum'', a perennial in the nightshade famil ...
in
pre-Hispanic
In the history of the Americas, the pre-Columbian era, also known as the pre-contact era, or as the pre-Cabraline era specifically in Brazil, spans from the initial peopling of the Americas in the Upper Paleolithic to the onset of European c ...
times. Before the expansion of the
Inca Empire
The Inca Empire, officially known as the Realm of the Four Parts (, ), was the largest empire in pre-Columbian America. The administrative, political, and military center of the empire was in the city of Cusco. The History of the Incas, Inca ...
, maize was traded and transported as far south as 40° S in Melinquina,
Lácar Department
Lácar is a department located in the south of Neuquén Province, Argentina.
Geography
The department is bounded by Huiliches Department to the north, Collón Cura Department to the northeast, Rio Negro Province to the southeast, Los Lagos ...
, Argentina, probably brought across the Andes from Chile.
Columbian exchange
After the arrival of Europeans in 1492, Spanish settlers consumed maize, and explorers and traders carried it back to Europe. Spanish settlers much preferred
wheat
Wheat is a group of wild and crop domestication, domesticated Poaceae, grasses of the genus ''Triticum'' (). They are Agriculture, cultivated for their cereal grains, which are staple foods around the world. Well-known Taxonomy of wheat, whe ...
bread to maize. Maize flour could not be substituted for wheat for communion bread, since in
Christian
A Christian () is a person who follows or adheres to Christianity, a Monotheism, monotheistic Abrahamic religion based on the life and teachings of Jesus in Christianity, Jesus Christ. Christians form the largest religious community in the wo ...
belief at that time only wheat could undergo
transubstantiation
Transubstantiation (; Greek language, Greek: μετουσίωσις ''metousiosis'') is, according to the teaching of the Catholic Church, "the change of the whole substance of sacramental bread, bread into the substance of the Body of Christ and ...
and be transformed into the body of Christ.
Maize spread to the rest of the world because of its ability to grow in diverse climates. It was cultivated in Spain just a few decades after Columbus's voyages and then spread to Italy,
West Africa
West Africa, also known as Western Africa, is the westernmost region of Africa. The United Nations geoscheme for Africa#Western Africa, United Nations defines Western Africa as the 16 countries of Benin, Burkina Faso, Cape Verde, The Gambia, Gha ...
, the
Philippines
The Philippines, officially the Republic of the Philippines, is an Archipelagic state, archipelagic country in Southeast Asia. Located in the western Pacific Ocean, it consists of List of islands of the Philippines, 7,641 islands, with a tot ...
and elsewhere. By the 17th century, it was a common peasant food in Southern Europe. By the 18th century, it was the chief food of the southern French and Italian peasantry, especially as
polenta
Polenta (, ) is an Italian cuisine, Italian dish of boiled cornmeal that was historically made from other grains. It may be allowed to cool and solidify into a loaf that can be baked, fried or Grilling, grilled.
The variety of cereal used is ...
in Italy.
When maize was introduced into Western farming systems, it was welcomed for its productivity. However, a widespread problem of malnutrition soon arose wherever it had become a
staple food
A staple food, food staple, or simply staple, is a food that is eaten often and in such quantities that it constitutes a dominant portion of a standard diet for an individual or a population group, supplying a large fraction of energy needs an ...
. Indigenous Americans had learned to soak maize in
alkali
In chemistry, an alkali (; from the Arabic word , ) is a basic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a soluble base has a pH greater than 7.0. The a ...
-watermade with ashes and limesince at least 1200–1500 BC, creating the process of nixtamalization. They did this to liberate the corn hulls, but coincidentally it also liberated the B-vitamin
niacin
Nicotinic acid, or niacin, is an organic compound and a vitamer of vitamin B3, an essential human nutrient. It is produced by plants and animals from the amino acid tryptophan.
Nicotinic acid is also a prescription medication. Amounts f ...
, the lack of which caused
pellagra
Pellagra is a disease caused by a lack of the vitamin niacin (vitamin B3). Symptoms include inflamed skin, diarrhea, dementia, and sores in the mouth. Areas of the skin exposed to friction and radiation are typically affected first. Over tim ...
. Once alkali processing and dietary variety were understood and applied, pellagra disappeared in the developed world. The development of high-
lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. Lysine contains an α-amino group (which is in the protonated form when the lysine is dissolved in water at physiological pH), an α-carboxylic acid group ( ...
maize and the promotion of a more balanced diet have contributed to its demise. Pellagra still exists in food-poor areas and refugee camps where people survive on donated maize.
Names
The name ''maize'' derives from the Spanish form of the
Taíno
The Taíno are the Indigenous peoples of the Caribbean, Indigenous peoples of the Greater Antilles and surrounding islands. At the time of European contact in the late 15th century, they were the principal inhabitants of most of what is now The ...
. The Swedish botanist
Carl Linnaeus
Carl Linnaeus (23 May 1707 – 10 January 1778), also known after ennoblement in 1761 as Carl von Linné,#Blunt, Blunt (2004), p. 171. was a Swedish biologist and physician who formalised binomial nomenclature, the modern system of naming o ...
used the common name maize as the species epithet in ''Zea mays''. The name ''maize'' is preferred in formal, scientific, and international usage as a
common name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often con ...
because it refers specifically to this one grain, unlike ''corn'', which has a complex variety of meanings that vary by context and geographic region. Most countries primarily use the term ''maize'', and the name ''corn'' is used mainly in the United States and a handful of other English-speaking countries. In countries that primarily use the term ''maize'', the word ''corn'' may denote any
cereal
A cereal is a grass cultivated for its edible grain. Cereals are the world's largest crops, and are therefore staple foods. They include rice, wheat, rye, oats, barley, millet, and maize ( Corn). Edible grains from other plant families, ...
crop, varying geographically with the local staple, such as wheat in England and oats in Scotland or Ireland. The usage of ''corn'' for maize started as a shortening of "
Indian corn
Maize (; ''Zea mays''), also known as corn in North American English, is a tall stout grass that produces cereal grain. It was domesticated by indigenous peoples in southern Mexico about 9,000 years ago from wild teosinte. Native Americans ...
" in 18th-century North America.
The historian of food Betty Fussell writes in an article on the history of the word ''corn'' in North America that " say the word ''corn'' is to plunge into the tragi-farcical mistranslations of language and history". Similar to the British usage, the Spanish referred to maize as , a generic term for cereal grains, as did Italians with the term . The British later referred to maize as Turkey wheat, Turkey corn, or Indian corn; Fussell comments that "they meant not a place but a condition, a savage rather than a civilized grain".
International groups such as the
Centre for Agriculture and Bioscience International
CABI (legally CAB International, formerly Commonwealth Agricultural Bureaux) is a nonprofit intergovernmental development and information organisation focusing primarily on agricultural and environmental issues in the developing world, and the ...
consider ''maize'' the preferred common name. The word ''maize'' is used by the UN's
Food and Agriculture Organization
The Food and Agriculture Organization of the United Nations; . (FAO) is a specialized agency of the United Nations that leads international efforts to defeat hunger and improve nutrition and food security. Its Latin motto, , translates ...
, and in the names of the
International Maize and Wheat Improvement Center
The International Maize and Wheat Improvement Center (known – even in English – by its Spanish acronym CIMMYT for ''Centro Internacional de Mejoramiento de Maíz y Trigo'') is a non-profit research-for-development organization that develops ...
of Mexico, the Indian Institute of Maize Research, the Maize Association of Australia, the National Maize Association of Nigeria, the National Maize Association of Ghana, the Maize Trust of South Africa, and the Zimbabwe Seed Maize Association.
Structure and physiology
Maize is a tall annual grass with a single stem, ranging in height from . The long narrow leaves arise from the
node
In general, a node is a localized swelling (a "knot") or a point of intersection (a vertex).
Node may refer to:
In mathematics
* Vertex (graph theory), a vertex in a mathematical graph
*Vertex (geometry), a point where two or more curves, lines ...
s or joints, alternately on opposite sides on the stalk. Maize is
monoecious
Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system comparable with gynomonoecy, andromonoecy and trimonoecy, and contras ...
, with separate male and female flowers on the same plant. At the top of the stem is the tassel, an
inflorescence
In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...
of male flowers; their anthers release pollen, which is dispersed by wind. Like other pollen, it is an
allergen
An allergen is an otherwise harmless substance that triggers an allergic reaction in sensitive individuals by stimulating an immune response.
In technical terms, an allergen is an antigen that is capable of stimulating a type-I hypersensitivi ...
, but most of it falls within a few meters of the tassel and the risk is largely restricted to farm workers.
The female inflorescence, some way down the stem from the tassel, is first seen as a silk, a bundle of soft tubular hairs, one for the
carpel
Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more ...
in each female flower, which develops into a kernel (often called a seed. Botanically, as in all grasses, it is a fruit, fused with the seed coat to form a
caryopsis
In botany, a caryopsis () is a type of simple fruit—one that is monocarpellate (formed from a single carpel) and indehiscent (not opening at maturity) and resembles an achene, except that in a caryopsis the pericarp is fused with the thin s ...
) when it is pollinated. A whole female inflorescence develops into an ear or
corncob
A corncob, also called corn cob or cob of corn, is the hard core of an ear of maize, bearing the kernels, made up of the chaff, woody ring, and pith. Corncobs contain mainly cellulose, hemicellulose, and lignin.
However, during several instance ...
, enveloped by multiple leafy layers or husks.
The is the leaf most closely associated with a particular developing ear. This leaf and those above it contribute over three quarters of the carbohydrate (
starch
Starch or amylum is a polymeric carbohydrate consisting of numerous glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants for energy storage. Worldwide, it is the most common carbohydrate in human diet ...
) that fills the grain.
The grains are usually yellow or white in modern varieties; other varieties have orange, red, brown,
blue
Blue is one of the three primary colours in the RYB color model, RYB colour model (traditional colour theory), as well as in the RGB color model, RGB (additive) colour model. It lies between Violet (color), violet and cyan on the optical spe ...
,
purple
Purple is a color similar in appearance to violet light. In the RYB color model historically used in the arts, purple is a secondary color created by combining red and blue pigments. In the CMYK color model used in modern printing, purple is ...
, or black grains. They are arranged in 8 to 32 rows around the cob; there can be up to 1200 grains on a large cob. Yellow maizes derive their color from
carotenoid
Carotenoids () are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, cana ...
s; red maizes are colored by
anthocyanin
Anthocyanins (), also called anthocyans, are solubility, water-soluble vacuole, vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart named a chemical compou ...
s and
phlobaphene
Phlobaphenes (or phlobaphens, CAS No.:71663-19-9) are reddish, alcohol-soluble and water-insoluble phenolic substances. They can be extracted from plants, or be the result from treatment of tannin extracts with mineral acids (tanner's red). The na ...
s; and orange and green varieties may contain combinations of these pigments.
Maize has short-day
photoperiodism
Photoperiod is the change of day length around the seasons. The rotation of the earth around its axis produces 24 hour changes in light (day) and dark (night) cycles on earth. The length of the light and dark in each phase varies across the season ...
, meaning that it requires nights of a certain length to flower. Flowering further requires enough warm days above . The control of flowering is set genetically; the physiological mechanism involves the
phytochrome
Phytochromes are a class of photoreceptor proteins found in plants, bacteria and fungi. They respond to light in the red and far-red regions of the visible spectrum and can be classed as either Type I, which are activated by far-red light, or ...
system. Tropical cultivars can be problematic if grown in higher latitudes, as the longer days can make the plants grow tall instead of setting seed before winter comes. On the other hand, growing tall rapidly could be convenient for producing biofuel.
Immature maize shoots accumulate a powerful antibiotic substance, 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (
DIMBOA
DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) is a naturally occurring hydroxamic acid, a benzoxazinoid. DIMBOA is a powerful antibiotic present in maize, wheat, rye, and related grasses,
DIMBOA was first identified in maize in 1962 as t ...
), which provides a measure of protection against a wide range of pests. Because of its shallow roots, maize is susceptible to droughts, intolerant of nutrient-deficient soils, and prone to being uprooted by severe winds.
File:Corntassel 7095.jpg , Many small male flowers make up the male inflorescence or tassel.
File:Cornsilk 7091.jpg , Female inflorescence, with young
silk
Silk is a natural fiber, natural protein fiber, some forms of which can be weaving, woven into textiles. The protein fiber of silk is composed mainly of fibroin and is most commonly produced by certain insect larvae to form cocoon (silk), c ...
File:GreenCorn.JPG , Stalks, ears and silk
File:ZeaMays.jpg , Full-grown maize plants
File:Klip kukuruza uzgojen u Međimurju (Croatia).JPG , Mature maize ear on a stalk
File:Männliche Blüte einer Maispflanze 2009-08-19.JPG , Male flowers
File:Corn blooming.jpg , Mature silk
Genomics and genetics
Maize is
diploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, ...
with 20
chromosome
A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...
s. 83% of
allelic
An allele is a variant of the sequence of nucleotides at a particular location, or locus, on a DNA molecule.
Alleles can differ at a single position through single nucleotide polymorphisms (SNP), but they can also have insertions and deletions ...
variation within the genome derives from its teosinte ancestors, primarily due to the freedom of ''Zea'' species to outcross.
Barbara McClintock
Barbara McClintock (June 16, 1902 – September 2, 1992) was an American scientist and cytogenetics, cytogeneticist who was awarded the 1983 Nobel Prize in Physiology or Medicine. McClintock received her PhD in botany from Cornell University ...
used maize to validate her
transposon
A transposable element (TE), also transposon, or jumping gene, is a type of mobile genetic element, a nucleic acid sequence in DNA that can change its position within a genome.
The discovery of mobile genetic elements earned Barbara McClinto ...
theory of "jumping genes", for which she won the 1983
Nobel Prize in Physiology or Medicine
The Nobel Prize in Physiology or Medicine () is awarded yearly by the Nobel Assembly at the Karolinska Institute for outstanding discoveries in physiology or medicine. The Nobel Prize is not a single prize, but five separate prizes that, acco ...
. Maize remains an important
model organism
A model organism is a non-human species that is extensively studied to understand particular biological phenomena, with the expectation that discoveries made in the model organism will provide insight into the workings of other organisms. Mo ...
for genetics and
developmental biology
Developmental biology is the study of the process by which animals and plants grow and develop. Developmental biology also encompasses the biology of Regeneration (biology), regeneration, asexual reproduction, metamorphosis, and the growth and di ...
. The
MADS-box
The MADS box is a conserved sequence motif. The genes which contain this motif are called the MADS-box gene family. The MADS box encodes the DNA-binding MADS domain. The MADS domain binds to DNA sequences of high similarity to the motif CC /TGG ...
motif is involved in the development of maize flowers.
The Maize Genetics and Genomics Database is funded by the
US Department of Agriculture
The United States Department of Agriculture (USDA) is an executive department of the United States federal government that aims to meet the needs of commercial farming and livestock food production, promotes agricultural trade and producti ...
to support maize research. The
International Maize and Wheat Improvement Center
The International Maize and Wheat Improvement Center (known – even in English – by its Spanish acronym CIMMYT for ''Centro Internacional de Mejoramiento de Maíz y Trigo'') is a non-profit research-for-development organization that develops ...
maintains a large collection of maize accessions tested and cataloged for insect resistance. In 2005, the US
National Science Foundation
The U.S. National Science Foundation (NSF) is an Independent agencies of the United States government#Examples of independent agencies, independent agency of the Federal government of the United States, United States federal government that su ...
, Department of Agriculture, and the
Department of Energy
A ministry of energy or department of energy is a government department in some countries that typically oversees the production of fuel and electricity; in the United States, however, it manages nuclear weapons development and conducts energy-rela ...
formed a consortium to sequence the maize
genome
A genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as ...
. The resulting
DNA
Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...
sequence data was deposited immediately into
GenBank
The GenBank sequence database is an open access, annotated collection of all publicly available nucleotide sequences and their protein translations. It is produced and maintained by the National Center for Biotechnology Information (NCBI; a par ...
, a public repository for genome-sequence data. Sequencing of the maize genome was completed in 2008. In 2009, the consortium published results of its sequencing effort. The genome, 85% of which is composed of
transposon
A transposable element (TE), also transposon, or jumping gene, is a type of mobile genetic element, a nucleic acid sequence in DNA that can change its position within a genome.
The discovery of mobile genetic elements earned Barbara McClinto ...
s, contains 32,540 genes. Much of it has been duplicated and reshuffled by helitrons, a group of
transposable element
A transposable element (TE), also transposon, or jumping gene, is a type of mobile genetic element, a nucleic acid sequence in DNA that can change its position within a genome.
The discovery of mobile genetic elements earned Barbara McClinto ...
s within maize's DNA.
Breeding
Conventional breeding
Maize breeding in prehistory resulted in large plants producing large ears. Modern
breeding
Breeding is sexual reproduction that produces offspring, usually animals or plants. It can only occur between a male and a female animal or plant.
Breeding may refer to:
* Animal husbandry, through selected specimens such as dogs, horses, and rab ...
began with individuals who selected highly productive varieties in their fields and then sold seed to other farmers. James L. Reid was one of the earliest and most successful, developing Reid's Yellow Dent in the 1860s. These early efforts were based on mass selection (a row of plants is grown from seeds of one parent), and the choosing of plants after pollination (which means that only the female parents are known). Later breeding efforts included ear to row selection (C. G. Hopkins c. 1896), hybrids made from selected
inbred
Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders an ...
lines (G. H. Shull, 1909), and the highly successful
double cross hybrid
In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two dif ...
s using four inbred lines ( D. F. Jones c. 1918, 1922). University-supported breeding programs were especially important in developing and introducing modern hybrids.
Since the 1940s, the best strains of maize have been first-generation hybrids made from inbred strains that have been optimized for specific traits, such as yield, nutrition, drought, pest and disease tolerance. Both conventional cross-breeding and genetic engineering have succeeded in increasing output and reducing the need for cropland, pesticides, water and fertilizer. There is conflicting evidence to support the hypothesis that maize yield potential has increased over the past few decades. This suggests that changes in yield potential are associated with leaf angle, lodging resistance, tolerance of high plant density, disease/pest tolerance, and other agronomic traits rather than increase of yield potential per individual plant.
Certain varieties of maize have been bred to produce many ears; these are the source of the "
baby corn
Baby corn (also known as young corn, cornlettes, child corn or baby sweetcorn) is a cereal grain taken from corn (maize) harvested early while the stalks are still small and immature. It typically is eaten whole—including the cob, which is o ...
" used as a vegetable in
Asian cuisine
Asian cuisine encompasses several significant regional cooking styles of Asia: Central Asian, East Asian, North Asian, South Asian, Southeast Asian, and West Asian. Cuisine is a distinctive way of cooking practices and customs, usually associat ...
. A fast-flowering variety named mini-maize was developed to aid scientific research, as multiple generations can be obtained in a single year. One strain called olotón has evolved a symbiotic relationship with
nitrogen-fixing
Nitrogen fixation is a chemical process by which molecular dinitrogen () is converted into ammonia (). It occurs both biologically and abiological nitrogen fixation, abiologically in chemical industry, chemical industries. Biological nitrogen ...
microbes, which provides the plant with 29%–82% of its nitrogen. The
International Maize and Wheat Improvement Center
The International Maize and Wheat Improvement Center (known – even in English – by its Spanish acronym CIMMYT for ''Centro Internacional de Mejoramiento de Maíz y Trigo'') is a non-profit research-for-development organization that develops ...
(CIMMYT) operates a conventional breeding program to provide optimized strains. The program began in the 1980s. Hybrid seeds are distributed in Africa by its Drought Tolerant Maize for Africa project.
Tropical
landrace
A landrace is a Domestication, domesticated, locally adapted, often traditional variety of a species of animal or plant that has developed over time, through adaptation to its natural and cultural Environment (biophysical), environment of agric ...
s remain an important and underused source of resistance alleles – both those for disease and for herbivores. Such alleles can then be introgressed into productive varieties. Rare alleles for this purpose were discovered by Dao and Sood, both in 2014. In 2018, Zerka Rashid of CIMMYT used its
association mapping In genetics, association mapping, also known as "linkage disequilibrium mapping", is a method of mapping quantitative trait locus, quantitative trait loci (QTLs) that takes advantage of historic linkage disequilibrium to link phenotypes (observable ...
panel, developed for tropical drought tolerance traits. to find new
genomic
Genomics is an interdisciplinary field of molecular biology focusing on the structure, function, evolution, mapping, and editing of genomes. A genome is an organism's complete set of DNA, including all of its genes as well as its hierarchical, ...
regions providing
sorghum downy mildew resistance
''Peronosclerospora sorghi'' is a plant pathogen. It is the causal agent of sorghum downy mildew. The pathogen is a fungal-like protist in the oomycota, or water mold, class. ''Peronosclerospora sorghi'' infects susceptible plants though sexual o ...
Genetically modified maize
Genetically modified maize ( corn) is a genetically modified crop. Specific maize strains have been genetically engineered to express agriculturally-desirable traits, including resistance to pests and to herbicides. Maize strains with both tr ...
was one of the 26
genetically engineered food
Genetically modified foods (GM foods), also known as genetically engineered foods (GE foods), or bioengineered foods are foods produced from organisms that have had changes introduced into their DNA using various methods of genetic engineering. G ...
crops grown commercially in 2016. The vast majority of this is
Bt maize
Genetically modified maize (maize, corn) is a genetically modified crop. Specific maize strains have been genetic engineering, genetically engineered to express agriculturally-desirable Phenotypic trait, traits, including resistance to pests and ...
. Genetically modified maize has been grown since 1997 in the United States and Canada; by 2016, 92% of the US maize crop was genetically modified. As of 2011, herbicide-tolerant maize and insect-resistant maize varieties were each grown in over 20 countries.
In September 2000, up to $50 million worth of food products were recalled due to the presence of
Starlink
Starlink is a satellite internet constellation operated by Starlink Services, LLC, an international telecommunications provider that is a wholly owned subsidiary of American aerospace company SpaceX, providing coverage to around 130 countries ...
genetically modified corn, which had been approved only for animal consumption.
Origin
External phylogeny
The maize
genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
''Zea'' is relatively closely related to
sorghum
''Sorghum bicolor'', commonly called sorghum () and also known as great millet, broomcorn, guinea corn, durra, imphee, jowar, or milo, is a species in the Poaceae, grass genus ''Sorghum (genus), Sorghum'' cultivated for its grain. The grain i ...
, both being in the
PACMAD clade
The PACMAD clade (previously PACCMAD, PACCAD, or PACC) is one of two major lineages (or clades) of the true grasses (Poaceae), regrouping six subfamilies and about 5700 species, more than half of all true grasses. Its sister group is the BOP cla ...
of Old World grasses, and much more distantly to
rice
Rice is a cereal grain and in its Domestication, domesticated form is the staple food of over half of the world's population, particularly in Asia and Africa. Rice is the seed of the grass species ''Oryza sativa'' (Asian rice)—or, much l ...
and
wheat
Wheat is a group of wild and crop domestication, domesticated Poaceae, grasses of the genus ''Triticum'' (). They are Agriculture, cultivated for their cereal grains, which are staple foods around the world. Well-known Taxonomy of wheat, whe ...
, which are in the other major group of grasses, the
BOP clade
The BOP clade (sometimes ''BEP clade'') is one of two major lineages (or clades) of undefined taxonomic rank in the grasses (Poaceae), containing more than 5,400 species, about half of all grasses. Well-known members of this clade include rice, ...
. It is closely related to ''
Tripsacum
''Tripsacum'' is a genus of plants in the Poaceae, grass family and native to the Western Hemisphere. Gamagrass is a common name for plants in this genus.
Species
References:
Formerly included
Reference:
See ''Anthephora''; ''Apluda''; ''Ch ...
teosinte
''Zea'' is a genus of flowering plants in the Poaceae, grass family. The best-known species is ''Z. mays'' (variously called maize, corn, or Indian corn), one of the most important crops for human societies throughout much of the world. The four ...
s, which are its
crop wild relative
A crop wild relative (CWR) is a wild plant closely related to a domesticated plant. It may be a wild ancestor of the domesticated (cultivated) plant or another closely related taxon.
Overview
The wild relatives of crop plants constitute an i ...
s. The teosinte origin theory was proposed by the Russian botanist
Nikolai Ivanovich Vavilov
Nikolai Ivanovich Vavilov ( rus, Никола́й Ива́нович Вави́лов, p=nʲɪkɐˈlaj ɪˈvanəvʲɪtɕ vɐˈvʲiləf, a=Ru-Nikolay_Ivanovich_Vavilov.ogg; – 26 January 1943) was a Russian and Soviet agronomist, botanist ...
in 1931, and the American
Nobel Prize
The Nobel Prizes ( ; ; ) are awards administered by the Nobel Foundation and granted in accordance with the principle of "for the greatest benefit to humankind". The prizes were first awarded in 1901, marking the fifth anniversary of Alfred N ...
-winner
George Beadle
George Wells Beadle (October 22, 1903 – June 9, 1989) was an American geneticist. In 1958 he shared one-half of the Nobel Prize in Physiology or Medicine with Edward Tatum for their discovery of the role of genes in regulating biochemical eve ...
in 1932. The two plants have dissimilar appearance, maize having a single tall stalk with multiple leaves and teosinte being a short, bushy plant. The difference between the two is largely controlled by differences in just two genes, called grassy tillers-1 (''gt1'', ) and teosinte branched-1 (''tb1'', ). In the late 1930s, Paul Mangelsdorf suggested that domesticated maize was the result of a hybridization event between an unknown wild maize and a species of ''
Tripsacum
''Tripsacum'' is a genus of plants in the Poaceae, grass family and native to the Western Hemisphere. Gamagrass is a common name for plants in this genus.
Species
References:
Formerly included
Reference:
See ''Anthephora''; ''Apluda''; ''Ch ...
'', a related genus; this has been refuted by modern
genetic testing
Genetic testing, also known as DNA testing, is used to identify changes in DNA sequence or chromosome structure. Genetic testing can also include measuring the results of genetic changes, such as RNA analysis as an output of gene expression, or ...
.
In 2004,
John Doebley
John F. Doebley is an American plant geneticist whose main area of interest is how genes drive plant development and evolution. He has spent the last two decades examining the genetic differences and similarities between teosinte and maize and has ...
identified Balsas teosinte, ''Zea mays'' subsp. ''parviglumis'', native to the
Balsas River
The Balsas River (Spanish Río Balsas, also locally known as the Mezcala River, or Atoyac River) is a major river of south-central Mexico.
The basin flows through the states of Guerrero, México, Morelos, and Puebla. Downstream of Ciudad Alt ...
valley in Mexico's southwestern highlands, as the
crop wild relative
A crop wild relative (CWR) is a wild plant closely related to a domesticated plant. It may be a wild ancestor of the domesticated (cultivated) plant or another closely related taxon.
Overview
The wild relatives of crop plants constitute an i ...
genetically most similar to modern maize. The middle part of the short Balsas River valley is the likely location of early domestication. Stone milling tools with maize residue have been found in an 8,700 year old layer of deposits in a cave not far from
Iguala, Guerrero
Iguala (), known officially as Iguala de la Independencia, is a historic city located from the state capital of Chilpancingo, in the Mexican state of Guerrero in southwestern Mexico.
Geography
The city of Iguala stands on Federal Highway 95 ...
. Doebley and colleagues showed in 2002 that maize had been domesticated only once, about 9,000 years ago, and then spread throughout the Americas.
Maize pollen dated to 7,300 years ago from San Andres, Tabasco has been found on the Caribbean coast. A primitive corn was being grown in southern Mexico, Central America, and northern South America 7,000 years ago. Archaeological remains of early maize ears, found at Guila Naquitz Cave in the
Oaxaca Valley
The Central Valleys () of Oaxaca, also simply known as the Oaxaca Valley, is a geographic region located within the modern-day state of Oaxaca in southeastern Mexico. In an administrative context, it has been defined as comprising the districts of ...
, are roughly 6,250 years old; the oldest ears from caves near Tehuacan, Puebla, are 5,450 years old.
Spreading to the north
Around 4,500 years ago, maize began to spread to the north. In the United States, maize was first cultivated at several sites in New Mexico and Arizona about 4,100 years ago. During the first millennium AD, maize cultivation spread more widely in the areas north. In particular, the large-scale adoption of maize agriculture and consumption in eastern North America took place about A.D. 900. Native Americans cleared large forest and grassland areas for the new crop. The rise in maize cultivation 500 to 1,000 years ago in what is now the southeastern United States corresponded with a decline of freshwater
mussel
Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other ...
s, which are very sensitive to environmental changes.
Agronomy
Growing
Because it is cold-intolerant, in the
temperate zones
In geography, the temperate climates of Earth occur in the middle latitudes (approximately 23.5° to 66.5° N/S of the Equator), which span between the tropics and the polar regions of Earth. These zones generally have wider temperature ran ...
maize must be planted in the spring. Its
root
In vascular plants, the roots are the plant organ, organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often bel ...
system is generally shallow, so the plant is dependent on soil moisture. As a plant that uses carbon fixation, maize is a considerably more water-efficient crop than plants that use carbon fixation such as
alfalfa
Alfalfa () (''Medicago sativa''), also called lucerne, is a perennial plant, perennial flowering plant in the legume family Fabaceae. It is cultivated as an important forage crop in many countries around the world. It is used for grazing, hay, ...
and
soybean
The soybean, soy bean, or soya bean (''Glycine max'') is a species of legume native to East Asia, widely grown for its edible bean. Soy is a staple crop, the world's most grown legume, and an important animal feed.
Soy is a key source o ...
s. Maize is most sensitive to drought at the time of silk emergence, when the flowers are ready for pollination. In the United States, a good harvest was traditionally predicted if the maize was "knee-high by the
Fourth of July
Independence Day, known colloquially as the Fourth of July, is a federal holiday in the United States which commemorates the ratification of the Declaration of Independence by the Second Continental Congress on July 4, 1776, establishing th ...
", although modern hybrids generally exceed this growth rate. Maize used for
silage
Silage is fodder made from green foliage crops which have been preserved by fermentation (food), fermentation to the point of souring. It is fed to cattle, sheep and other ruminants. The fermentation and storage process is called ''ensilage'', ' ...
is harvested while the plant is green and the fruit immature. Sweet corn is harvested in the "milk stage", after pollination but before starch has formed, between late summer and early to mid-autumn. Field maize is left in the field until very late in the autumn to thoroughly dry the grain, and may, in fact, sometimes not be harvested until winter or even early spring. The importance of sufficient soil moisture is shown in many parts of Africa, where periodic
drought
A drought is a period of drier-than-normal conditions.Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, ...
regularly causes maize crop failure and consequent
famine
A famine is a widespread scarcity of food caused by several possible factors, including, but not limited to war, natural disasters, crop failure, widespread poverty, an Financial crisis, economic catastrophe or government policies. This phenom ...
. Although it is grown mainly in wet, hot climates, it can thrive in cold, hot, dry or wet conditions, meaning that it is an extremely versatile crop.
Maize was planted by the Native Americans in small hills of soil, in the
polyculture
In agriculture, polyculture is the practice of growing more than one crop species together in the same place at the same time, in contrast to monoculture, which had become the dominant approach in developed countries by 1950. Traditional example ...
system called the Three Sisters. Maize provided support for
bean
A bean is the seed of some plants in the legume family (Fabaceae) used as a vegetable for human consumption or animal feed. The seeds are often preserved through drying (a ''pulse''), but fresh beans are also sold. Dried beans are traditi ...
s; the beans provided nitrogen derived from nitrogen-fixing
rhizobia
Rhizobia are diazotrophic bacteria that fix nitrogen after becoming established inside the root nodules of legumes (Fabaceae). To express genes for nitrogen fixation, rhizobia require a plant host; they cannot independently fix nitrogen. I ...
bacteria which live on the roots of beans and other
legume
Legumes are plants in the pea family Fabaceae (or Leguminosae), or the fruit or seeds of such plants. When used as a dry grain for human consumption, the seeds are also called pulses. Legumes are grown agriculturally, primarily for human consum ...
s; and
squashes
Squash most often refers to:
* Squash (sport), the high-speed racquet sport also known as squash racquets
* Squash (plant), the fruit of vines of the genus ''Cucurbita''
Squash may also refer to: Sports
* Squash (professional wrestling), an extr ...
provided ground cover to stop weeds and inhibit evaporation by providing shade over the soil.
File:Plàntules moresc 2012.JPG, Seedlings three weeks after sowing
File:Corn Zea mays Plant Row 2000px.jpg, Young stalks
File:Maispflanze.jpg, Mature plants showing ears
Harvesting
Sweet corn, harvested earlier than maize grown for grain, grows to maturity in a period of from 60 to 100 days according to variety. An extended sweet corn harvest, picked at the milk stage, can be arranged either by planting a selection of varieties that ripen earlier and later, or by planting different areas at fortnightly intervals.
Maize harvested as a grain crop can be kept in the field a relatively long time, even months, after the crop is ready to harvest; it can be harvested and stored in the husk leaves if kept dry.
According to the U.S. Department of Agriculture, in the four decades from 1855 to 1894 the amount of labor required to produce one bushel of maize declined from four hours and thirty four minutes to only forty-one minutes. Before 1940, most maize in North America was harvested by hand. This involved a large number of workers and associated social events (husking or shucking
bees
Bees are winged insects closely related to wasps and ants, known for their roles in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamil ...
). From the 1850s onward, some machinery became available to partially mechanize the processes, such as one- and two-row mechanical pickers (picking the ear, leaving the
stover
Stover are the leaves and stalks of field crops, such as corn (maize), sorghum or soybean that are commonly left in a field after harvesting the grain. It is similar to straw, the residue left after any cereal grain or grass has been harvested ...
) and corn binders, which are
reaper-binder
The reaper-binder, or binder, is a farm implement that improved upon the simple reaper. The binder was invented in 1872 by Charles Baxter Withington, a jeweler from Janesville, Wisconsin. In addition to cutting the small-grain crop, a binder als ...
s designed specifically for maize. The latter produce sheaves that can be shocked. By hand or mechanical picker, the entire ear is harvested, which requires a separate operation of a maize sheller to remove the kernels from the ear. Whole ears of maize were often stored in
corn crib
A corn crib or corncrib is a type of granary used to dry and store corn. It may also be known as a cornhouse or corn house.
Overview
After the harvest and while still on the cob, corn is placed in the crib either with or without the husk. The ...
s, sufficient for some livestock feeding uses. Today corn cribs with whole ears, and corn binders, are less common because most modern farms harvest the grain from the field with a
combine harvester
The modern combine harvester, also called a combine, is a machine designed to harvest a variety of cultivated seeds. Combine harvesters are one of the most economically important labour-saving inventions, significantly reducing the fraction of ...
and store it in bins. The combine with a corn head (with points and snap rolls instead of a reel) does not cut the stalk; it simply pulls the stalk down. The stalk continues downward and is crumpled into a mangled pile on the ground, where it usually is left to become
organic matter
Organic matter, organic material or natural organic matter is the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have come fro ...
for the
soil
Soil, also commonly referred to as earth, is a mixture of organic matter, minerals, gases, water, and organisms that together support the life of plants and soil organisms. Some scientific definitions distinguish dirt from ''soil'' by re ...
. The ear of maize is too large to pass between slots in a plate as the snap rolls pull the stalk away, leaving only the ear and husk to enter the machinery. The combine separates the husk and the cob, keeping only the kernels.
File:Iowa harvest 2009.jpg, Harvesting maize, Iowa
File:Maissipelto Rantasalmi.jpg, Harvesting maize, Finland
File:MyanmarCorn3.jpg, Hand-picking maize, Myanmar
File:Africa Food Security 11 (10665081134).jpg, Dehusking maize by hand,
Malawi
Malawi, officially the Republic of Malawi, is a landlocked country in Southeastern Africa. It is bordered by Zambia to the west, Tanzania to the north and northeast, and Mozambique to the east, south, and southwest. Malawi spans over and ...
Grain storage
Drying is vital to prevent or at least reduce damage by
mould
A mold () or mould () is one of the structures that certain fungi can form. The dust-like, colored appearance of molds is due to the formation of spores containing fungal secondary metabolites. The spores are the dispersal units of the fungi ...
fungi, which contaminate the grain with
mycotoxin
A mycotoxin (from the Greek μύκης , "fungus" and τοξικός , "poisonous") is a toxic secondary metabolite produced by fungi and is capable of causing disease and death in both humans and other animals. The term 'mycotoxin' is usually rese ...
s. ''
Aspergillus
' () is a genus consisting of several hundred mold species found in various climates worldwide.
''Aspergillus'' was first catalogued in 1729 by the Italian priest and biologist Pier Antonio Micheli. Viewing the fungi under a microscope, Miche ...
'' and ''
Fusarium
''Fusarium'' (; ) is a large genus of filamentous fungi, part of a group often referred to as hyphomycetes, widely distributed in soil and associated with plants. Most species are harmless saprobes, and are relatively abundant members of the s ...
'' spp. are the most common mycotoxin sources, and accordingly important in agriculture. If the moisture content of the harvested grain is too high, grain dryers are used to reduce the moisture content by blowing heated air through the grain. This can require large amounts of energy in the form of combustible gases (
propane
Propane () is a three-carbon chain alkane with the molecular formula . It is a gas at standard temperature and pressure, but becomes liquid when compressed for transportation and storage. A by-product of natural gas processing and petroleum ref ...
or
natural gas
Natural gas (also fossil gas, methane gas, and gas) is a naturally occurring compound of gaseous hydrocarbons, primarily methane (95%), small amounts of higher alkanes, and traces of carbon dioxide and nitrogen, hydrogen sulfide and helium ...
) and electricity to power the blowers.
Production
Maize is widely cultivated throughout the world, and a greater weight of maize is produced each year than any other grain. In 2020, total world production was 1.16 billion
tonne
The tonne ( or ; symbol: t) is a unit of mass equal to 1,000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton in the United States to distinguish it from the non-metric units of the s ...
s, led by the United States with 31.0% of the total (table). China produced 22.4% of the global total.
File:Production of maize (2019).svg, Production of maize (2019)
File:World Production Of Primary Crops, Main Commodities.svg, Maize (pink strip) is the second most widely produced primary crop, after
sugarcane
Sugarcane or sugar cane is a species of tall, Perennial plant, perennial grass (in the genus ''Saccharum'', tribe Andropogoneae) that is used for sugar Sugar industry, production. The plants are 2–6 m (6–20 ft) tall with stout, jointed, fib ...
, and the first among grain crops.
Pests
Many pests can affect maize growth and development, including invertebrates, weeds, and pathogens.
Maize is susceptible to a large number of fungal, bacterial, and viral
plant disease
Plant diseases are diseases in plants caused by pathogens (infectious organisms) and environmental conditions (physiological factors). Organisms that cause infectious disease include fungi, oomycetes, bacteria, viruses, viroids, virus-like or ...
s. Those of economic importance include diseases of the leaf, smuts such as
corn smut
Corn smut is a plant disease caused by the pathogenic fungus ''Mycosarcoma maydis'', synonym ''Ustilago maydis''. One of several cereal crop pathogens called smut, the fungus forms galls on all above-ground parts of corn species such as maize ...
, ear rots and stalk rots.
Northern corn leaf blight
Northern corn leaf blight (NCLB) or Turcicum leaf blight (TLB) is a foliar disease of corn (maize) caused by ''Exserohilum turcicum'', the anamorph of the Ascomycota, ascomycete ''Setosphaeria turcica''. With its characteristic cigar-shaped lesion ...
damages maize throughout its range, whereas banded leaf and sheath blight is a problem in Asia. Some fungal diseases of maize produce potentially dangerous
mycotoxin
A mycotoxin (from the Greek μύκης , "fungus" and τοξικός , "poisonous") is a toxic secondary metabolite produced by fungi and is capable of causing disease and death in both humans and other animals. The term 'mycotoxin' is usually rese ...
s such as
aflatoxin
Aflatoxins are various toxicity, poisonous carcinogens and mutagens that are produced by certain Mold (fungus), molds, especially ''Aspergillus'' species such as ''Aspergillus flavus'' and ''Aspergillus parasiticus''. According to the USDA, "The ...
. In the United States, major diseases include
tar spot Tar spot may refer to:
*'' Phyllachora maydis'', a fungus species that cause tar spot disease of maize
*'' Rhytisma acerinum'', a fungus species that causes tar spot disease of maples
{{Short pages monitor.
The corn smut fungus, known as ''
huitlacoche
Corn smut is a plant disease caused by the pathogenic fungus ''Mycosarcoma maydis'', synonym (taxonomy), synonym ''Ustilago maydis''. One of several cereal crop pathogens called smut (fungus), smut, the fungus forms galls on all above-ground p ...
'', which grows on maize, is a Mexican delicacy.
Coarse maize meal is made into a thick
porridge
Porridge is a food made by heating, soaking or boiling ground, crushed or chopped starchy plants, typically grain, in milk or water. It is often cooked or served with added flavourings such as sugar, honey, fruit, or syrup to make a sweet cereal ...
in many cultures: from the
polenta
Polenta (, ) is an Italian cuisine, Italian dish of boiled cornmeal that was historically made from other grains. It may be allowed to cool and solidify into a loaf that can be baked, fried or Grilling, grilled.
The variety of cereal used is ...
of Italy, the ''angu'' of Brazil, the ''
mămăligă
Mămăligă (;) is a polenta-like dish made out of yellow maize flour, traditional in Romania, Moldova, south-west regions of Ukraine and among Poles in Ukraine (''mamałyga''), Hungary (''puliszka''), the Black Sea regions of Georgia (country), ...
'' of Romania, to
cornmeal mush
Mush is a type of cornmeal pudding (or porridge) which is usually boiled in water or milk. It is often allowed to set, or gel into a semisolid, then cut into flat squares or rectangles, and pan fried. Cornmeal mush is especially popular amongst ...
in the US (or
hominy
Hominy is a food item produced from dried maize (corn) kernels that have been treated with an alkali, in a process called nixtamalization ( is the Nahuatl word for "hominy"). "Lye hominy" is a type of hominy made with lye.
History
The process ...
grits
Grits (stylized as GRITS) is an American Christian hip hop group from Nashville, Tennessee. Their name is an acronym, which stands for "Grammatical Revolution In the Spirit". GRITS is made up of Stacey "Coffee" Jones and Teron "Bonafide" Carter ...
in the Southern US) or the food called
mieliepap
Ugali, also known as posho, nsima, papa, pap, sadza, isitshwala, akume, amawe, ewokple, akple, and #Names, other names, is a type of maize, corn meal made from maize flour, maize or corn or ''mahindi'' flour in several African countries: Kenya, ...
in South Africa and sadza, nshima, ugali and other names in other parts of Africa. Introduced into Africa by the Portuguese in the 16th century, maize has become Africa's most important staple food crop.
Sweet corn
Sweet corn (''Zea mays'' convar. ''saccharata'' var. ''rugosa''), also called sweetcorn, sugar corn and pole corn, is a variety of maize grown for human consumption with a high sugar content. Sweet corn is the result of a naturally occurring rec ...
, a genetic variety that is high in sugars and low in starch, is eaten in the unripe state as
corn on the cob
Corn on the cob is a culinary term for a cooked ear of sweet corn (maize) eaten directly off the cob. The ear is picked while the endosperm is in the "milk stage" so that the kernels are still tender. Ears of corn are steamed, boiled, or gr ...
.
File:Corn, the food of the nation, US Food Administration poster, 1918.jpg, Poster of maize-based foods, US Food Administration, 1918
File:Summer corn (48286638996).jpg, Semi-peeled corn on the cob
File:ChiapasTamale2.JPG, Mexican
tamales
A tamale, in Spanish , is a traditional Mesoamerican dish made of ''masa'', a dough made from nixtamalized corn, which is steamed in a corn husk or banana leaves. The wrapping can either be discarded prior to eating or used as a plate. Tam ...
File:Polenta.jpg, One way of serving Italian
polenta
Polenta (, ) is an Italian cuisine, Italian dish of boiled cornmeal that was historically made from other grains. It may be allowed to cool and solidify into a loaf that can be baked, fried or Grilling, grilled.
The variety of cereal used is ...
Nutritional value
Raw, yellow, sweet maize kernels are composed of 76% water, 19%
carbohydrates
A carbohydrate () is a biomolecule composed of carbon (C), hydrogen (H), and oxygen (O) atoms. The typical hydrogen-to-oxygen atomic ratio is 2:1, analogous to that of water, and is represented by the empirical formula (where ''m'' and ''n'' ma ...
, 3%
protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
, and 1%
fat
In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food.
The term often refers specif ...
(table). In a 100-
gram
The gram (originally gramme; SI unit symbol g) is a Physical unit, unit of mass in the International System of Units (SI) equal to one thousandth of a kilogram.
Originally defined in 1795 as "the absolute Mass versus weight, weight of a volume ...
serving, maize kernels provide 86
calories
The calorie is a unit of energy that originated from the caloric theory of heat. The large calorie, food calorie, dietary calorie, kilocalorie, or kilogram calorie is defined as the amount of heat needed to raise the temperature of one liter o ...
and are a good source (10–19% of the
Daily Value
In the U.S. and Canada, the Reference Daily Intake (RDI) is used in nutrition labeling on food and dietary supplement products to indicate the daily intake level of a nutrient that is considered to be sufficient to meet the requirements of 97� ...
) of the
B vitamins
B vitamins are a class of water-soluble vitamins that play important roles in Cell (biology), cell metabolism and synthesis of red blood cells. They are a chemically diverse class of compounds.
Dietary supplements containing all eight are referr ...
,
thiamin
Thiamine, also known as thiamin and vitamin B1, is a vitamin – an essential micronutrient for humans and animals. It is found in food and commercially synthesized to be a dietary supplement or medication. Phosphorylated forms of thiam ...
,
niacin
Nicotinic acid, or niacin, is an organic compound and a vitamer of vitamin B3, an essential human nutrient. It is produced by plants and animals from the amino acid tryptophan.
Nicotinic acid is also a prescription medication. Amounts f ...
pantothenic acid
Pantothenic acid (vitamin B5) is a B vitamin and an essential nutrient. All animals need pantothenic acid in order to synthesize coenzyme A (CoA), which is essential for cellular energy production and for the synthesis and degradation of prote ...
(B5) and
folate
Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and ...
. Maize has suboptimal amounts of the
essential amino acid
An essential amino acid, or indispensable amino acid, is an amino acid that cannot be synthesized from scratch by the organism fast enough to supply its demand, and must therefore come from the diet. Of the 21 amino acids common to all life forms ...
s
tryptophan
Tryptophan (symbol Trp or W)
is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α-carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromat ...
and
lysine
Lysine (symbol Lys or K) is an α-amino acid that is a precursor to many proteins. Lysine contains an α-amino group (which is in the protonated form when the lysine is dissolved in water at physiological pH), an α-carboxylic acid group ( ...
, which accounts for its lower status as a protein source. The proteins of beans and legumes complement those of maize.
Animal feed
Maize is a major source of
animal feed
Animal feed is food given to domestic animals, especially livestock, in the course of animal husbandry. There are two basic types: fodder and forage. Used alone, the word ''feed'' more often refers to fodder. Animal feed is an important input ...
. As a grain crop, the dried
kernels
Kernel may refer to:
Computing
* Kernel (operating system), the central component of most operating systems
* Kernel (image processing), a matrix used for image convolution
* Compute kernel, in GPGPU programming
* Kernel method, in machine learnin ...
are used as feed. They are often kept on the cob for storage in a
corn crib
A corn crib or corncrib is a type of granary used to dry and store corn. It may also be known as a cornhouse or corn house.
Overview
After the harvest and while still on the cob, corn is placed in the crib either with or without the husk. The ...
, or they may be shelled off for storage in a
grain bin
Grain bins are bulk storage structures for dry wheat, soybean, maize, oats, barley and more. Grain bins are cylinders made of corrugated sheets or sheet metal with a coned metal roof that has vents. The floors of grain bins have aeration sys ...
. When the grain is used for feed, the rest of the plant (the
corn stover
Corn stover consists of the leaves, stalks, and cobs of corn (maize) (''Zea mays'' ssp. ''mays'' L.) plants left in a field after harvest. Such stover makes up about half of the yield of a corn crop and is similar to straw from other cere ...
) can be used later as
fodder
Fodder (), also called provender (), is any agriculture, agricultural foodstuff used specifically to feed domesticated livestock, such as cattle, domestic rabbit, rabbits, sheep, horses, chickens and pigs. "Fodder" refers particularly to food ...
,
bedding
Bedding, also called bedclothes or bed linen, is the materials laid above the mattress of a bed for hygiene, warmth, protection of the mattress, and decorative effect. Bedding is the removable and washable portion of a human sleeping environment ...
(litter), or
soil conditioner
A soil conditioner is a product which is added to soil to improve the soil’s physical qualities, usually its fertility (ability to provide nutrition for plants) and sometimes its mechanics. In general usage, the term "soil conditioner" is often ...
. When the whole maize plant (grain plus stalks and leaves) is used for fodder, it is usually chopped and made into
silage
Silage is fodder made from green foliage crops which have been preserved by fermentation (food), fermentation to the point of souring. It is fed to cattle, sheep and other ruminants. The fermentation and storage process is called ''ensilage'', ' ...
, as this is more digestible and more palatable to ruminants than the dried form. Traditionally, maize was gathered into shocks after harvesting, where it dried further. It could then be stored for months until fed to livestock. Silage can be made in
silo
A silo () is a structure for storing Bulk material handling, bulk materials.
Silos are commonly used for bulk storage of grain, coal, cement, carbon black, woodchips, food products and sawdust. Three types of silos are in widespread use toda ...
s or in silage wrappers. In the tropics, maize is harvested year-round and fed as green forage to the animals. Baled cornstalks offer an alternative to
hay
Hay is grass, legumes, or other herbaceous plants that have been cut and dried to be stored for use as animal fodder, either for large grazing animals raised as livestock, such as cattle, horses, goats, and sheep, or for smaller domesticate ...
for
animal feed
Animal feed is food given to domestic animals, especially livestock, in the course of animal husbandry. There are two basic types: fodder and forage. Used alone, the word ''feed'' more often refers to fodder. Animal feed is an important input ...
, alongside direct
grazing
In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to free range (roam around) and consume wild vegetations in order to feed conversion ratio, convert the otherwise indigestible (by human diges ...
of maize grown for this purpose.
File:Corn By-Product Used for Livestock Feed.jpg, Cattle wait alongside a fence as a truck distributes a grain feed composed of corn by-products into troughs.
File:Bales from corn stems 01.jpg, Baled cornstalks
Chemicals
Starch from maize can be made into
plastics
Plastics are a wide range of synthetic or semisynthetic materials composed primarily of polymers. Their defining characteristic, plasticity, allows them to be molded, extruded, or pressed into a diverse range of solid forms. This adaptab ...
,
fabric
Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, and different types of fabric. At first, the word "textiles" only referred to woven fabrics. However, weaving is no ...
s,
adhesive
Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation.
The use of adhesives offers certain advantage ...
s, and many other chemical products. Corn steep liquor, a plentiful watery byproduct of maize
wet milling Wet-milling is a process in which feed material is steeped in water, with or without sulfur dioxide, to soften the seed kernel in order to help separate the kernel’s various components. For example, wet-milling plants can separate a 56-pound bu ...
process, is used in the biochemical industry and research as a culture medium to grow
microorganism
A microorganism, or microbe, is an organism of microscopic scale, microscopic size, which may exist in its unicellular organism, single-celled form or as a Colony (biology)#Microbial colonies, colony of cells. The possible existence of unseen ...
s.
Biofuel
Feed maize is being used for heating; specialized corn stoves (similar to wood stoves) use either feed maize or wood pellets to generate heat. Maize cobs can be used as a
biomass
Biomass is a term used in several contexts: in the context of ecology it means living organisms, and in the context of bioenergy it means matter from recently living (but now dead) organisms. In the latter context, there are variations in how ...
fuel source. Home-heating furnaces which use maize kernels as a fuel have a large hopper that feeds the kernels into the fire. Maize is used as a feedstock for the production of
ethanol fuel
Ethanol fuel is fuel containing ethyl alcohol, the same type of alcohol as found in alcoholic beverages. It is most often used as a motor fuel, mainly as a biofuel additive for gasoline.
Several common ethanol fuel mixtures are in use aro ...
. The price of food is indirectly affected by the use of maize for biofuel production: use of maize for biofuel production increases the demand, and therefore the price of maize. A pioneering biomass gasification power plant in Strem,
Burgenland
Burgenland (; ; ; Bavarian language, Austro-Bavarian: ''Burgnland''; Slovene language, Slovene: ''Gradiščanska''; ) is the easternmost and least populous Bundesland (Austria), state of Austria. It consists of two statutory city (Austria), statut ...
, Austria, started operating in 2005. It would be possible to create
diesel
Diesel may refer to:
* Diesel engine, an internal combustion engine where ignition is caused by compression
* Diesel fuel, a liquid fuel used in diesel engines
* Diesel locomotive, a railway locomotive in which the prime mover is a diesel engine ...
from the biogas by the Fischer Tropsch method.
File:Haase anaerobic digester.JPG, Farm-based maize silage digester near
Neumünster
Neumünster () is a city in the middle of Schleswig-Holstein, Germany. With more than 79,000 registered inhabitants, it is the fourth-largest municipality in Schleswig-Holstein (behind Kiel, Lübeck and Flensburg). The ''Holstenhallen'' and ...
, Germany, 2007, using whole maize plants, not just the grain. The green tarpaulin top cover is held up by the biogas stored in the digester.
In human culture
In Mesoamerica, maize is seen as a vital force, deified as a
maize god
Like other Mesoamerican peoples, the traditional Maya recognize in their staple crop, maize, a vital force with which they strongly identify. This is clearly shown by their mythological traditions. According to the 16th-century Popol Vuh, the Hero ...
, usually female. In the United States, maize ears are carved into column capitals in the
United States Capitol
The United States Capitol, often called the Capitol or the Capitol Building, is the Seat of government, seat of the United States Congress, the United States Congress, legislative branch of the Federal government of the United States, federal g ...
building. The Corn Palace in Mitchell, South Dakota, uses cobs and ears of colored maize to implement a mural design that is recycled annually. The concrete '' Field of Corn'' sculpture in
Dublin, Ohio
Dublin is a city in the U.S. state of Ohio. A suburb of Columbus, Ohio, Columbus, it falls within the jurisdictions of Franklin County, Ohio, Franklin, Delaware County, Ohio, Delaware, Union County, Ohio, Union, and Madison County, Ohio, Madison ...
depicts hundreds of ears of corn in a grassy field. A maize stalk with two ripe ears is depicted on the reverse of the Croatian 1 lipa coin, minted since 1993.
Maize kernels have sometimes denoted
cowardice
Cowardice is a characteristic wherein excessive fear prevents an individual from taking a risk or facing danger. It is the opposite of courage. As a label, "cowardice" indicates a failure of character in the face of a challenge. One who succumb ...
, as maize is fed to chickens, which symbolise cowards. In the months before the
1973 Chilean coup d'etat
Events January
* January 1 – The United Kingdom, the Republic of Ireland and Denmark 1973 enlargement of the European Communities, enter the European Economic Community, which later becomes the European Union.
* January 14 - The 16-0 19 ...
El Mostrador
El Mostrador is a Chilean online newspaper, founded on 1 March 2000. Its current president is Germán Olmedo Acedvedo and its director is Federico Joannon Errázuriz.
History
''El Mostrador'' was launched on 1 March 2000 and is Chile's first excl ...
Larco Museum
The Larco Museum (officially known as Rafael Larco Herrera Archaeological Museum, in ) is a privately owned museum of pre-Columbian art, located in the Pueblo Libre District of Lima, Peru. The museum is housed in an 18th-century vice-royal build ...
,
Lima
Lima ( ; ), founded in 1535 as the Ciudad de los Reyes (, Spanish for "City of Biblical Magi, Kings"), is the capital and largest city of Peru. It is located in the valleys of the Chillón River, Chillón, Rímac River, Rímac and Lurín Rive ...
, Peru
File:Mayan - Stucco Portrait Head - Walters 20092026 - Three Quarter Right.jpg, Stucco head of the
Maya maize god
Like other Mesoamerican peoples, the traditional Maya civilization, Maya recognize in their staple crop, maize, a vital force with which they strongly identify. This is clearly shown by their mythological traditions. According to the 16th-century ...
from Campeche, Mexico, 550–850 AD
File:Young Corn God MET DT9945.jpg,
Jaina Island
Jaina Island is a pre-Columbian Maya archaeological site and artificial island in the present-day Mexican state of Campeche. A small limestone island on the Yucatán Peninsula's Gulf coast with only a tidal inlet separating it from the mainland, J ...
ceramic statuette of the young
Maya maize god
Like other Mesoamerican peoples, the traditional Maya civilization, Maya recognize in their staple crop, maize, a vital force with which they strongly identify. This is clearly shown by their mythological traditions. According to the 16th-century ...
emerging from an ear of corn, 600–900 AD
File:Aztecs storing maize.jpg,
Aztecs
The Aztecs ( ) were a Mesoamerican civilization that flourished in central Mexico in the post-classic period from 1300 to 1521. The Aztec people included different ethnic groups of central Mexico, particularly those groups who spoke the ...
Water tower
A water tower is an elevated structure supporting a water tank constructed at a height sufficient to pressurize a water distribution system, distribution system for potable water, and to provide emergency storage for fire protection. Water towe ...
in
Rochester, Minnesota
Rochester is a city in Olmsted County, Minnesota, United States, and its county seat. It is located along rolling bluffs on the Zumbro River's south fork in Southeast Minnesota. At the 2020 United States census, 2020 census, the city had a popul ...
being painted as an ear of maize, 2008
See also
*
Detasseling
Detasseling corn is removing the pollen-producing flowers, the tassel, from the tops of corn (maize) plants and placing them on the ground. It is a form of pollination control,Post-harvest losses (grains)
*
Push–pull technology
Push–pull may refer to:
In electronic technology
*Push–pull output, type of electronic circuit
* Push–pull converter, in electronics, is a type of DC to DC converter that uses a transformer
* Push–pull connector, an electronic cable conne ...
, pest control strategy for maize and
sorghum
''Sorghum bicolor'', commonly called sorghum () and also known as great millet, broomcorn, guinea corn, durra, imphee, jowar, or milo, is a species in the Poaceae, grass genus ''Sorghum (genus), Sorghum'' cultivated for its grain. The grain i ...
*
Zein
Zein ( ) is a class of prolamine protein found in maize. It is usually manufactured as a powder from corn gluten meal. Zein is one of the best understood plant proteins.Momany, Frank A.; Sessa, David J.; Lawton, John C.; Selling, Gordon W.; Ha ...
References
Further reading
* Byerlee, Derek. "The globalization of hybrid maize, 1921–70." ''
Journal of Global History
The ''Journal of Global History'' is a triannual peer-reviewed academic history journal covering the study of comparative, world, and global history. It was established in 2006 and is published by Cambridge University Press. The editor-in-chief ...
'' 15.1 (2020): 101–122.
* Clampitt, Cynthia. ''Maize: How Corn Shaped the U.S. Heartland'' (2015)
*
Maize
Maize (; ''Zea mays''), also known as corn in North American English, is a tall stout grass that produces cereal grain. It was domesticated by indigenous peoples in southern Mexico about 9,000 years ago from wild teosinte. Native American ...