Amaranthus is a cosmopolitan group of more than 50 species which make up the genus of annual plant or short-lived collectively known as amaranths. Some of the better known names include "prostrate pigweed" and "love lies bleeding".
Catkin-like cymes of densely-packed flowers grow in summer or fall. Amaranth varies in flower, leaf, and stem color with a range of striking Plant pigments from the spectrum of maroon to crimson and can grow longitudinally from tall with a cylindrical, Succulent plant, fibrous stem that is hollow with grooves and when mature. There are approximately 75 species in the genus, 10 of which are dioecious and native to North America, and the remaining 65 are monoecious species that are endemic to every continent (except Antarctica) from tropical lowlands to the Himalayas. Members of this genus share many characteristics and uses with members of the closely related genus Celosia. Amaranth grain is collected from the genus. The leaves of some species are also eaten.
The form amaranthus (with H), comes from an erroneous association with the Greek etymon (lat. -anthus) meaning , found in the name of many plants (agapanthus, for example).
Its denominations in the languages of the peoples cultivating it since ancient times in America are huauhtli in Nahuatl, kiwicha, ataĉo in Quechua, tez or xtes in Mayan languages, ahparie in Purépecha, wa've in Huichol language, and guegui in Tarahumara.
Amaranth has a primary root with deeper spreading secondary fibrous root structures. are in the form a large panicle that varies from terminal to axial, color, and sex. The tassel of fluorescence is either erect or bent and varies in width and length between species. Flowers are radially symmetric and either bisexual or unisexual with very small, bristly perianth and pointy . Species in this genus are either monecious (e.g. A. hybridus,) or dioecious (e.g. A. palmeri). Fruits are in the form of capsules referred to as a unilocular pixdio that opens at maturity. The top (operculum) of the unilocular pixdio releases the urn that contains the seed. Seeds are circular form from 1 to 1.5 millimeters in diameter and range in color with a shiny, smooth seed coat. The panicle is harvested 200 days after cultivation with approximately 1,000 to 3,000 seeds harvested per gram.
In 1955, Sauer classified the genus into two subgenera, differentiating only between monoecious and dioecious species: Acnida (L.) Aellen ex K.R. Robertson and Amaranthus. Although this classification was widely accepted, further infrageneric classification was (and still is) needed to differentiate this widely diverse group. Mosyakin and Robertson 1996 later divided into three subgenera: Acnida, Amaranthus, and Albersia. The support for the addition of the subdivision Albersia because of its indehiscent fruits coupled with three elliptic to linear to be exclusive characters to members of this subgenus. The classification of these groups are further supported with a combination of floral characters, reproductive strategies, geographic distribution, and molecular evidence.
The phylogenies of Amaranthus using maximum parsimony and Bayesian analysis of Nuclear gene and chloroplast suggest five within the genus: Diecious / Pumilus, Hybris, Galapagos, Eurasian/ South African, Australian (ESA), ESA + South American.
Amaranthus includes three recognised subgenera and 75 species, although species numbers are questionable due to hybridisation and species concepts. Infrageneric classification focuses on inflorescence, flower characters and whether a species is monoecious/dioecious, as in the Sauer (1955) suggested classification. Bracteole morphology present on the stem is used for taxonomic classification of Amaranth. Wild species have longer bracteoles compared to cultivated species. A modified infrageneric classification of Amaranthus includes three subgenera: Acnida, Amaranthus, and Albersia, with the taxonomy further differentiated by sections within each of the subgenera.
There is near certainty that A. hypochondriacus is the common ancestor to the cultivated grain species, however the later series of domestication to follow remains unclear. There has been opposing hypotheses of a single as opposed to multiple domestication events of the three grain species. There is evidence of phylogenetic and geographical support for clear groupings that indicate separate domestication events in South America and Central America. A. hybridus may derive from South America, whereas A. caudatus, A. hypochondriacus, and A. quentiensis are native to Central and North America.
A new herbicide-resistant strain of A. palmeri has appeared; it is glyphosate-resistant and so cannot be killed by herbicides using the chemical. Also, this plant can survive in tough conditions. The species Amaranthus palmeri (Palmer amaranth) causes the greatest reduction in soybean yields and has the potential to reduce yields by 17-68% in field experiments. Palmer amaranth is among the "top five most troublesome weeds" in the southeast of the United States and has already evolved resistances to dinitroaniline herbicides and acetolactate synthase inhibitors.Culpepper et al. (2006). Glyphosate-resistant Palmer amaranth ( Amaranthus palmeri) confirmed in Georgia. Weed Science 54: 620–626. This makes the proper identification of Amaranthus species at the seedling stage essential for agriculturalists. Proper weed control needs to be applied before the species successfully colonizes in the crop field and causes significant yield reductions.
An evolutionary lineage of around 90 species within the genus has acquired the carbon fixation pathway, which increases their photosynthetic efficiency. This probably occurred in the Miocene.
Cooking decreases its nutritional value substantially across all nutrients, with only dietary minerals remaining at moderate levels. Cooked amaranth leaves are a rich source of vitamin A, vitamin C, calcium, and manganese, with moderate levels of folate, iron, magnesium, and potassium. Amaranth does not contain gluten.
While all species are believed to be native to the Americas, several have been cultivated and introduced to warm regions worldwide. Amaranth's cosmopolitan distribution makes it one of many plants providing evidence of pre-Columbian oceanic contact. The earliest archeological evidence for amaranth in the Old World was found in an excavation in Narhan, India, dated to 1000–800 BCE.
Because of its importance as a symbol of indigenous culture, its palatability, ease of cooking, and a protein that is particularly well-suited to human nutritional needs, interest in amaranth seeds (especially A. cruentus and A. hypochondriacus) revived in the 1970s. It was recovered in Mexico from wild varieties and is now commercially cultivated. It is a popular snack in Mexico, sometimes mixed with chocolate or puffed rice, and its use has spread to Europe and other parts of North America.
Seeds of Amaranth grain have been found in Antofagasta de la Sierra Department, Catamarca, Argentina in the southern Puna desert of the north of Argentina dating from 4,500 years ago, with evidence suggesting earlier use. Archeological digs unearthed A. cruentus seeds in a cave in Tehuacán, Mexico that dated to 6,000 years before present, while other digs in the same caves found A. hypochondriacus seeds dating to 1500 years before present.
Ancient amaranth grains still used include the three species Amaranthus caudatus, A. cruentus, and A. hypochondriacus. Evidence from single-nucleotide polymorphisms and chromosome structure supports A. hypochondriacus as the common ancestor of the three grain species.
It has been proposed as an inexpensive native crop that could be cultivated by indigenous people in rural areas for several reasons:
In the United States, the amaranth crop is mostly used for seed production. Most amaranth in American food products starts as a ground flour, blended with wheat or other flours to create cereals, crackers, cookies, bread or other baked products. Despite utilization studies showing that amaranth can be blended with other flours at levels above 50% without affecting functional properties or taste, most commercial products use amaranth only as a minor portion of their ingredients despite them being marketed as "amaranth" products.
In Uttar Pradesh and Bihar in India, it is called chaulai and is a popular red leafy vegetable (referred to in the class of vegetable preparations called laal saag). It is called chua in Kumaun area of Uttarakhand, where it is a popular red-green vegetable. In Karnataka in India, it is called harive soppu (ಹರಿವೆ ಸೊಪ್ಪು). It is used to prepare curries such as hulee, palya, majjigay-hulee, and so on. In Kerala, it is called cheera and is consumed by stir-frying the leaves with spices and red chili peppers to make a dish called cheera thoran. In Tamil Nadu, it is called mulaikkira and is regularly consumed as a favourite dish, where the greens are steamed and mashed with light seasoning of salt, red chili pepper, and cumin. It is called keerai masial. In the states of Andhra Pradesh and Telangana and other Telugu speaking regions of the country, this leaf is called as " Thotakura" and is cooked as a standalone curry, added as a part of mix leafy vegetable curry or added in preparation of a popular dal called thotakura pappu (తోటకూర పప్పు) in (Telugu language). In Maharashtra, it is called shravani maath and is available in both red and white colour. In Orissa, it is called khada saga, it is used to prepare saga bhaja, in which the leaf is fried with chili and onions. In West Bengal, the green variant is called Notey Shaak (নটে শাক) and the red variant is called Laal Shaak (লাল শাক ).
In China, the leaves and stems are used as a stir-fry vegetable, or in soups. In Vietnam, it is called rau dền and is used to make soup. Two species are popular as edible vegetable in Vietnam: dền đỏ ( Amaranthus tricolor) and dền cơm or dền trắng ( Amaranthus viridis).
In Bantu regions of Uganda and western Kenya, it is known as doodo or litoto.
In the Caribbean, the leaves are called bhaji in Trinidad and callaloo in Jamaica, and are sautéed with onions, garlic, and tomatoes, or sometimes used in a soup called pepperpot soup.
Amaranths are recorded as food plants for some Lepidoptera (butterfly and moth) species including the nutmeg moth and various case-bearer moths of the genus Coleophora: C. amaranthella, C. enchorda (feeds exclusively on Amaranthus), C. immortalis (feeds exclusively on Amaranthus), C. lineapulvella, and C. versurella (recorded on A. spinosus).
Amaranth is associated with longevity and, poetically, with death and immortality. Amaranth garlands were used in the mourning of Achilles.
John Milton's Paradise Lost portrays a showy amaranth in the Garden of Eden, "remov'd from Heav'n" when it blossoms because the flowers "shade the fountain of life". He describes amaranth as "immortal" in reference to the flowers that generally do not wither and retain bright reddish tones of color, even when deceased; referred to in one species as "love-lies-bleeding."
Species
Etymology
Ecology
Uses
Nutrition
History
Seed
Leaves, roots, and stems
Asia
Africa
Europe
Americas
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Dyes
Ornamentals
Culture
Gallery
See also
Further reading
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