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72-589: The province had a population of 2,019,555 according to the 2014 census, of which 48% are in urban areas. The foundation of the Central Plateau is a vast slab of primeval crystalline rock that frequently outcrops in the form of isolated rocks or massive peaks. The most prominent peak in the province is Mt. Môco in Londuimbali, with 2,620 metres. The peak is the highest point in Angola . The headwaters of

144-439: A Mount Moco Special Reserve has been proposed, the area currently has no protection status or measures in place. The forest continues to be at risk from the local residents of the village of Kanjonde, which sits at the foot of Mount Moco. As they depend primarily on subsistence farming, the villagers frequently burn vegetation and fell trees to make way for food cultivation in the mountain's valleys. Kanjonde has no electricity, so

216-814: 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 landraces 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 panel, developed for tropical drought tolerance traits. to find new genomic regions providing sorghum downy mildew resistance , and to further characterize known differentially methylated regions . Genetically modified maize

288-403: 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 for the soil . 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

360-578: A few showers during September, increase during October and November, have a break of two to four weeks in December, January or February, and continue until the end of April. The heaviest rainfall is usually in November or December. The Province of Huambo has an area of 35,771.15 km. It is divided into 11 municipalities that are sub-divided into 37 communes. It borders the Province of Kuanza Sul to

432-408: A large cob. Yellow maizes derive their color from carotenoids ; red maizes are colored by anthocyanins and phlobaphenes ; and orange and green varieties may contain combinations of these pigments. Maize has short-day photoperiodism , meaning that it requires nights of a certain length to flower. Flowering further requires enough warm days above 10 °C (50 °F). The control of flowering

504-499: 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. Maize is diploid with 20 chromosomes . 83% of allelic variation within the genome derives from its teosinte ancestors, primarily due to the freedom of Zea species to outcross . Barbara McClintock used maize to validate her transposon theory of "jumping genes", for which she won

576-410: A moderate climate. The annual variation of temperature is small, with maximum temperatures varying between 17 and 28 °C during much of the year. The average maximum is approximately 22 °C. During the winter months (May–July), temperatures may reach as low as 5 to 8 °C. Mean annual rainfall varies from 800 to 1600 mm, according to region. In the Central Plateau, seasonal rains begin with

648-638: A place but a condition, a savage rather than a civilized grain". International groups such as the Centre for Agriculture and Bioscience International consider maize the preferred common name. The word maize is used by the UN's Food and Agriculture Organization , and in the names of the International Maize and Wheat Improvement Center of Mexico, the Indian Institute of Maize Research,

720-601: A plant that uses C 4 carbon fixation , maize is a considerably more water-efficient crop than plants that use C 3 carbon fixation such as alfalfa and soybeans . 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 ", although modern hybrids generally exceed this growth rate. Maize used for silage

792-624: A significant produce of Huambo thanks to the favourable altitude and weather conditions of the Province, and is currently being reintroduced as the main crop in many farms of the region. Approximately 25 basic health facilities are operational within the Province, run by the Government or humanitarian agencies, covering 547,500 people in Huambo city and the municipality of Caála. According to the World Health Organization and

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864-433: A total of 530,000 t. As a result of improved security, areas used for cultivation in the Province have increased during the past years to about 500 km. This represents the largest increase in the country since the end of the war. The principal cereal crop is maize with 1950 km under cultivation. Yields are low, only 40 t/km, compared with yields of between 50 and 120 t/km in other provinces. The second cereal crop

936-477: Is a problem in Asia. Some fungal diseases of maize produce potentially dangerous mycotoxins such as aflatoxin . In the United States, major diseases include tar spot , bacterial leaf streak , gray leaf spot , northern corn leaf blight, and Goss's wilt ; in 2022, the most damaging disease was tar spot, which caused losses of 116.8 million bushels . Maize sustains a billion dollars' worth of losses annually in

1008-674: 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 planted it alongside beans and squashes in the Three Sisters polyculture . The leafy stalk of the plant gives rise to male inflorescences or tassels which produce pollen , and female inflorescences called ears . The ears yield grain, known as kernels 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

1080-408: Is composed of transposons , contains 32,540 genes. Much of it has been duplicated and reshuffled by helitrons , a group of transposable elements within maize's DNA. Maize breeding in prehistory resulted in large plants producing large ears. Modern breeding began with individuals who selected highly productive varieties in their fields and then sold seed to other farmers. James L. Reid was one of

1152-537: 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 and diseases ; two major insect pests, European corn borer and corn rootworms , have each caused annual losses of a billion dollars in the US. Modern plant breeding has greatly increased output and qualities such as nutrition, drought tolerance, and tolerance of pests and diseases. Much maize

1224-414: 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

1296-465: Is largely under-researched and has been visited by very few botanical surveyors. It is known to have several species of Protea and other flowering plants, many of which appear in July through September after grassland fires have settled. Mount Moco is home to many birds, with around 233 species recorded at the site. It has been designated an Important Bird Area (IBA) by BirdLife International and

1368-543: Is millet/ sorghum with approximately 160 km under production. Grain production has increased significantly in recent years. Total output rose to a peak of 159,000 t in the 1997/1998 season compared to only 17,000 t in 1993/1994. Climate and pest conditions forced production back to 115,000 t in 1998/1999 and to an estimated 88,000 t in 1999/2000. Other crops produced in the province include beans (450 km) and manioc (415 km), sweet potatoes (95 km) and Irish potatoes (32 km). Coffee ( Arabica type) used to be

1440-533: Is now genetically modified . As a food, maize is used to make a wide variety of dishes including Mexican tortillas and tamales , Italian polenta , and American hominy grits . Maize protein is low in some essential amino acids , and the niacin it contains only becomes available if freed by alkali treatment . In Mesoamerica, maize is deified as a maize god and depicted in sculptures. Maize requires human intervention for it to propagate. The kernels of its naturally-propagating teosinte ancestor fall off

1512-712: Is part of the Western Angola Endemic Bird Area . The mountain provides a home for a number of endangered and threatened bird species including the Swiersta's Francolin ( Pternistis swierstrai ), Angola Cave Chat ( Xenocopsychus ansorgei ), Angola Slaty Flycatcher ( Dioptrornis brunneus ) and Ludwig's Double-collared Sunbird ( Cinnyris ludovicensis ). Mount Moco is a particularly threatened habitat due to unsustainable wood collection for construction-based logging and for firewood. Uncontrolled bush fires are also an environmental threat. Though

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1584-577: Is represented also by 3 Delegates who report to their Ministry and to the Governor: Finance, Justice and Interior. The rest of Ministerial Delegations became Directorates after a reform introduced in June 1998: Health, Education, Energy and Water, Urbanism, Agriculture, Social Assistance, strengthening thus even more the power of the Governor to whom they report. All 11 Municipalities are headed by

1656-468: Is set genetically; the physiological mechanism involves the phytochrome 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 ), which provides

1728-498: Is shown in many parts of Africa, where periodic drought regularly causes maize crop failure and consequent famine . 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 system called the Three Sisters . Maize provided support for beans ;

1800-557: Is the domesticated variant of the four species of teosintes , which are its crop wild relatives . The teosinte origin theory was proposed by the Russian botanist Nikolai Ivanovich Vavilov in 1931, and the American Nobel Prize -winner George Beadle 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

1872-581: Is the highest mountain in Angola . It is located in Huambo Province in the western part of the country, 70 kilometres (43 mi) west of the city of Huambo . Mount Moco was named one of Angola's "seven wonders" in 2014. The mountain is a destination for birdwatchers, hikers, and people participating in rappelling and paragliding. The mountain's Afromontane forests are part of the Angolan montane forest-grassland mosaic bioregion. Mount Moco

1944-405: 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 ) that fills the grain. The grains are usually yellow or white in modern varieties; other varieties have orange, red, brown, blue , purple , or black grains. They are arranged in 8 to 32 rows around the cob; there can be up to 1200 grains on

2016-612: The Balsas River valley in Mexico's southwestern highlands, as the crop wild relative 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 . Doebley and colleagues showed in 2002 that maize had been domesticated only once, about 9,000 years ago, and then spread throughout

2088-705: The Columbian exchange , it has become a staple food in many parts of the world, with the total production of maize surpassing that of wheat and rice . Much maize is used for animal feed , whether as grain or as the whole plant, which can either be baled or made into the more palatable silage . Sugar-rich varieties called sweet corn are grown for human consumption, while field corn varieties are used for animal feed, for uses such as cornmeal or masa , corn starch , corn syrup , pressing into corn oil , alcoholic beverages like bourbon whiskey , and as chemical feedstocks including ethanol and other biofuels . Maize

2160-561: The Kunene River rise on the Central Plateau near Huambo town. Much of the soil in Huambo Province is of poor quality, and has been impoverished in many areas by overuse and erosion. However, it is generally of better quality than in the adjoining regions to the east, north and south. Striking differences can be observed between the vegetation of the highlands and the lower zone towards the coast. One characteristic feature of

2232-607: The 1983 Nobel Prize in Physiology or Medicine . Maize remains an important model organism for genetics and developmental biology . The MADS-box motif is involved in the development of maize flowers. The Maize Genetics and Genomics Database is funded by the US Department of Agriculture to support maize research. The International Maize and Wheat Improvement Center maintains a large collection of maize accessions tested and cataloged for insect resistance. In 2005,

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2304-662: 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 , are roughly 6,250 years old; the oldest ears from caves near Tehuacan , Puebla, are 5,450 years old. Around 4,500 years ago, maize began to spread to

2376-479: The B-vitamin niacin , the lack of which caused pellagra . Once alkali processing and dietary variety were understood and applied, pellagra disappeared in the developed world. The development of high- lysine 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. The name maize derives from

2448-709: 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. Maize is a tall annual grass with a single stem, ranging in height from 1.2 m (4 ft) to 4 m (13 ft). The long narrow leaves arise from the nodes or joints, alternately on opposite sides on

2520-893: The Ministry of Health, this represents an average of one facility per 20,778 people, close to the Angolan average of one health unit per 20,000 people. In Huambo, one health unit serves 18,000 people while in Caála, one unit covers 33,000 people. The provincial hospital is based in Huambo city. Vaccination coverage in Huambo city is higher than in other municipalities. In Huambo city, 16 vaccination posts cover 89,800 children under five years of age (one post per 5,600 children). In Caála, two posts cover 19,700 children (2002). Approximately 40 primary and three secondary schools operate in Huambo city (2001). Five schools target displaced children. In Caála, seven schools target displaced children. In Huambo,

2592-420: The Province is unknown. An average of eight mine accidents per month are reported. Mine accident statistics are gathered by humanitarian agencies through Huambo Central Hospital where all mine-related injuries are referred. Demining activities happen throughout the Province and are currently being implemented by an International NGO . Other humanitarian institutions provide ongoing mine awareness programmes. During

2664-586: The Spanish form maíz of the Taíno mahis . The Swedish botanist Carl Linnaeus 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 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

2736-562: The US National Science Foundation , Department of Agriculture, and the Department of Energy formed a consortium to sequence the maize genome . The resulting DNA sequence data was deposited immediately into GenBank , 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

2808-534: The US from each of two major insect pests , namely the European corn borer or ECB ( Ostrinia nubilalis ) and corn rootworms ( Diabrotica spp ) western corn rootworm , northern corn rootworm , and southern corn rootworm . Another serious pest is the fall armyworm ( Spodoptera frugiperda ). The maize weevil ( Sitophilus zeamais ) is a serious pest of stored grain. The Northern armyworm, Oriental armyworm or Rice ear-cutting caterpillar ( Mythimna separata )

2880-418: The beans provided nitrogen derived from nitrogen-fixing rhizobia bacteria which live on the roots of beans and other legumes ; and squashes provided ground cover to stop weeds and inhibit evaporation by providing shade over the soil. 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

2952-613: 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 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 in Italy. When maize

Huambo Province - Misplaced Pages Continue

3024-653: The civilian Administrators, under whom come 35 Communal Administrators. These have their own politically appointed Regedores (textually, Rulers) and the traditional leaders, the Sobas , who have lost much of their ancestral significance in the decision – making process. Two trans-African automobile routes intersect in Huambo: Huambo is the richest agricultural province in Angola. In 1999 the Province produced almost 22% of total national cereal production: 115,000 t out of

3096-646: The coastal area is the baobab ( Adansonia Digitata , or imbondeiro, in Portuguese). Tropical forests can also be found in the areas that receive significant rainfall. Until recently, the highlands were covered with a variety of trees; today, however, except in isolated areas in Bailundo and other regions, grasslands have taken the place of forest and woodland. Traditional methods of agriculture, slash-and-burn techniques ( queimadas ) and overpopulation by large concentrations of people displaced from their homes during

3168-577: The cob on their own, while those of domesticated 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 valley of south-central Mexico. Maize reached highland Ecuador at least 8000 years ago. It reached lower Central America by 7600 years ago, and

3240-425: 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 lines (G. H. Shull, 1909), and

3312-413: 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 cribs , 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 and store it in bins . The combine with

3384-774: The expansion of the Inca Empire , maize was traded and transported as far south as 40° S in Melinquina, Lácar Department , Argentina, probably brought across the Andes from Chile. 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 bread to maize. Maize flour could not be substituted for wheat for communion bread, since in Christian belief at that time only wheat could undergo transubstantiation and be transformed into

3456-532: The highly successful double cross hybrids 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

3528-550: The history of the word corn in North America that "[t]o 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 panizo , a generic term for cereal grains, as did Italians with the term polenta . The British later referred to maize as Turkey wheat, Turkey corn, or Indian corn; Fussell comments that "they meant not

3600-419: The machinery. The combine separates the husk and the cob, keeping only the kernels. Drying is vital to prevent or at least reduce damage by mould fungi, which contaminate the grain with mycotoxins . Aspergillus and Fusarium 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

3672-450: The main water treatment plant has not functioned properly since 1975 and the 400 km of water pipes are in poor condition. The population is currently dependent on wells for water access. During recent years, considerable work in the sector was undertaken by the Government and humanitarian agencies, including construction of 550 family latrines and 25 wells in villages and communities. The number of mines and unexploded ordnance ( UXO ) in

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3744-413: The milk stage, can be arranged either by planting a selection of varieties which 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. Before World War II , most maize in North America

3816-427: The moisture content by blowing heated air through the grain. This can require large amounts of energy in the form of combustible gases ( propane or natural gas ) and electricity to power the blowers. 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 tonnes , led by the United States with 31.0% of

3888-567: The native rural areas and functional deficiencies of the Civil Administration make difficult to accurately estimate population figures. The Huambo Provincial Department of Statistics and Planning reports that 419,000, or approximately 22% of the population, are children under five years of age. Source : Ministry of Planning, 2003 The province is headed by a Governor, currently Faustino Muteka, assisted by two vice-governors (Social and Economical Affairs). The central Government

3960-501: 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

4032-400: 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 mussels , which are very sensitive to environmental changes. Because it is cold-intolerant, in the temperate zones maize must be planted in the spring. Its root system is generally shallow, so the plant is dependent on soil moisture. As

4104-465: 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

4176-595: The northwest, Bie to the north and east, Benguela to the west, and Huila to the south. According to the Provincial Department of Statistics and Planning, Huambo is a relatively populated province with 1,948,000 people (approximately 15% of the estimated national of 12.6 million). More than half, 55%, of the population is urbanized, concentrated in Huambo City (822,000 people) and Caála Municipality (239,000 people). Recent population movements towards

4248-760: The presence of Starlink genetically modified corn, which had been approved only for animal consumption. The maize genus Zea is relatively closely related to sorghum , both being in the PACMAD clade of Old World grasses, and much more distantly to rice and wheat , which are in the other major group of grasses, the BOP clade . It is closely related to Tripsacum , gamagrass. various grasses e.g. fescue , ryegrass Hordeum (barley) Triticum (wheat) Oryza (rice) Pennisetum (fountaingrasses) Sorghum (sorghum) Tripsacum (gamagrass) Zea mays (maize) other Zea species ( teosintes ) Maize

4320-641: The residents also depend on wood fuel for cooking. The Mount Moco Project is a charitable foundation working to gain protection status for Mount Moco and to educate the Kanjonde villagers about more sustainable practices. The Project began a native tree nursery in July 2010 at Kanjonde, and this nursery was expanded in 2012 with permission of the village's soba (chief), Amândio Cabo. Maize Maize / m eɪ z / ( Zea mays ), also known as corn in North American English ,

4392-491: The source of the " baby corn " used as a vegetable in Asian cuisine . 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 microbes, which provides the plant with 29%–82% of its nitrogen. The International Maize and Wheat Improvement Center (CIMMYT) operates

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4464-415: The stalk. Maize is monoecious , with separate male and female flowers on the same plant. At the top of the stem is the tassel, an inflorescence of male flowers; their anthers release pollen, which is dispersed by wind . Like other pollen, it is an allergen , 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

4536-425: The stem from the tassel, is first seen as a silk, a bundle of soft tubular hairs , one for the carpel 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 ) when it is pollinated. A whole female inflorescence develops into an ear or corncob , enveloped by multiple leafy layers or husks. The ear leaf

4608-608: 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 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 " in 18th-century North America. The historian of food Betty Fussell writes in an article on

4680-472: The total (table). China produced 22.4% of the global total. 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 diseases . Those of economic importance include diseases of the leaf, smuts such as corn smut , ear rots and stalk rots. Northern corn leaf blight damages maize throughout its range, whereas banded leaf and sheath blight

4752-500: The two is largely controlled by differences in just two genes, called grassy tillers-1 ( gt1 , A0A317YEZ1 ) and teosinte branched-1 ( tb1 , Q93WI2 ). 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 , a related genus; this has been refuted by modern genetic testing . In 2004, John Doebley identified Balsas teosinte, Zea mays subsp. parviglumis , native to

4824-589: The valleys of the Colombian Andes between 7000 and 6000 years ago. The earliest maize plants grew a single, small ear per plant. The Olmec and Maya cultivated maize in numerous varieties throughout Mesoamerica ; they cooked, ground and processed it through nixtamalization . By 3000 years ago, maize was central to Olmec culture, including their calendar, language, and myths. The Mapuche people of south-central Chile cultivated maize along with quinoa and potatoes in pre-Hispanic times. Before

4896-500: The war (1975–2002) have caused significant deforestation. The use of wood fuel for the Benguela Railway until the 1980s was also responsible for deforestation . Large extensions of native forest have been cut down and replaced by rapid-growing and soil-depleting eucalyptus and pine trees. The Central Plateau is well within the tropical zone, but altitude and the effect of the southwestern Antarctic current combine to produce

4968-563: The year 2002, 145,000 people participated in these programmes. Mine awareness activities include theatre and puppet shows as well as exhibitions in schools and internally displaced people camps. Additionally, ten-minute radio programmes on the dangers of mines are broadcast two times per week. Up to 1991, the official name was Provincial Commissioner 12°30′S 15°40′E  /  12.500°S 15.667°E  / -12.500; 15.667 Mount Moco Mount Moco (Portuguese: Morro do Moco ), at 2,620 metres (8,600 ft),

5040-458: Was harvested by hand. This involved a large number of workers and associated social events (husking or shucking bees ). From the 1890s onward, some machinery became available to partially mechanize the processes, such as one- and two-row mechanical pickers (picking the ear, leaving the stover ) and corn binders, which are reaper-binders designed specifically for maize. The latter produce sheaves that can be shocked . By hand or mechanical picker,

5112-425: 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 . Indigenous Americans had learned to soak maize in alkali -water — made with ashes and lime — since at least 1200–1500 BC, creating the process of nixtamalization. They did this to liberate the corn hulls, but coincidentally it also liberated

5184-466: Was one of the 26 genetically engineered food crops grown commercially in 2016. The vast majority of this is Bt maize . 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

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