Gossypium
Encyclopedia
- For information on cotton production, industry, history, and applications, see cottonCottonCotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
.
Gossypium is the cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
. It belongs to the tribe Gossypieae
Gossypieae
Gossypieae is a tribe of the Malvoideae subfamily of flowering plants. It includes the cotton and related plants. It is distinguished from the Hibisceae tribe on the basis of embryo structure and its apparently unique possession of glands able to synthesize the pigment...
, in the mallow
Malva
Malva is a genus of about 25–30 species of herbaceous annual, biennial, and perennial plants in the family Malvaceae , one of several closely related genera in the family to bear the common English name mallow. The genus is widespread throughout the temperate, subtropical and tropical regions of...
family, Malvaceae
Malvaceae
Malvaceae, or the mallow family, is a family of flowering plants containing over 200 genera with close to 2,300 species. Judd & al. Well known members of this family include okra, jute and cacao...
, native to the tropical and subtropical regions from both the Old
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
and New World
New World
The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...
. The genus Gossypium comprises around 50 species , making it the largest in species number in the tribe Gosssypioieae. New species continue to be discovered. The name of the genus is derived from the Arabic
Arabic language
Arabic is a name applied to the descendants of the Classical Arabic language of the 6th century AD, used most prominently in the Quran, the Islamic Holy Book...
word goz, which refers to a soft substance.
Cotton is the primary natural fibre used by modern human
Human
Humans are the only living species in the Homo genus...
s. Cultivated cotton is also a major oilseed crop as well as a main protein source for animal feed. Cotton plants thus have an enormous weight in the world economy and are of great importance for the agriculture, industry and trade of many tropical and sub-tropical countries in Africa, South-America and Asia. Consequently the genus Gossypium has long attracted the attention of scientists.
The origin of the genus Gossypium is dated to around 5-10 million years ago. Gossypium species are distributed in arid to semi-arid regions of the tropics and sub-tropics. Generally shrubs or shrub-like plants, the species of this genus are extraordinarily diverse in morphology and adaptation, ranging from fire-adapted, herbaceous perennials in Australia to trees in Mexico.
Cultivated cottons are perennial shrubs most often grown as annuals. Plants are 1-2 m high in modern cropping systems, sometimes higher in traditional, multianual cropping systems, now largely disappearing. The leaves are broad and lobed, with three to five (or rarely seven) lobes. The seeds are contained in a capsule
Capsule (fruit)
In botany a capsule is a type of simple, dry fruit produced by many species of flowering plants. A capsule is a structure composed of two or more carpels that in most cases is dehiscent, i.e. at maturity, it splits apart to release the seeds within. A few capsules are indehiscent, for example...
called a boll, each seed surrounded by fibres of two types. These fibres are the more commercially interesting part of the plant and they are separated from the seed by a process called ginning. At the first ginning the longer fibres, called staples, are removed and these are twisted together to form yarn for making thread and weaving into high quality textiles. At the second ginning the shorter fibres, called linters, are removed, and these are woven into lower quality textiles (which include the eponymous lint). Commercial species of cotton plant are G. hirsutum
Gossypium hirsutum
Gossypium hirsutum, known as Upland Cotton or Mexican Cotton, is the most widely planted species of cotton in the United States, constituting some 95% of all cotton production and is native to Central America and possibly Mexico Worldwide, the figure is about 90% of all production for this...
(>90% of world production), G. barbadense
Gossypium barbadense
Gossypium barbadense, also known as extra long staple cotton as it generally has a staple of at least 1 3/8" or longer, is a species of cotton plant. Some types of ELS cotton are American Pima, Egyptian Giza, Indian Suvin, Chinese Xiniang, Sudanese Barakat, and Russian Tonkovoloknistyi...
(3-4%), G. arboreum
Gossypium arboreum
Gossypium arboreum, commonly called tree cotton, is a species of cotton native to India and Pakistan and other tropical and subtropical regions of the Old World. There is evidence of its cultivation as long ago as the Harappan civilization of the Indus Valley for the production of cotton textiles...
and G. herbaceum
Gossypium herbaceum
Gossypium herbaceum, also called Levant cotton, is a species of cotton native to the semi-arid regions of sub-Saharan Africa and Arabia where it still grows in the wild as a perennial shrub...
(together, 2%). Many varieties of cotton have been developed by selective breeding and hybridization of these species. Experiments are ongoing to cross-breed various desirable traits of wild cotton species into the principal commercial species, such as resistance to insects and diseases, and drought-tolerance. Cotton fibres occur naturally in colours of white, brown, green, and some mixing of these.
Most wild cottons are diploid
Ploidy
Ploidy is the number of sets of chromosomes in a biological cell.Human sex cells have one complete set of chromosomes from the male or female parent. Sex cells, also called gametes, combine to produce somatic cells. Somatic cells, therefore, have twice as many chromosomes. The haploid number is...
, but there is a group of five species from America and Pacific islands which are tetraploid, apparently due to a single hybridization event around 1.5 to 2 million years ago. The tetraploid species are G. hirsutum
Gossypium hirsutum
Gossypium hirsutum, known as Upland Cotton or Mexican Cotton, is the most widely planted species of cotton in the United States, constituting some 95% of all cotton production and is native to Central America and possibly Mexico Worldwide, the figure is about 90% of all production for this...
, G. tomentosum
Gossypium tomentosum
Gossypium tomentosum, commonly known as Mao or Hawaiian cotton, is a species of cotton plant that is endemic to the Hawaiian Islands. It inhabits low shrublands at elevations from sea level to . Mao is a shrub that reaches a height of and a diameter of...
, G. mustelinum, G. barbadense
Gossypium barbadense
Gossypium barbadense, also known as extra long staple cotton as it generally has a staple of at least 1 3/8" or longer, is a species of cotton plant. Some types of ELS cotton are American Pima, Egyptian Giza, Indian Suvin, Chinese Xiniang, Sudanese Barakat, and Russian Tonkovoloknistyi...
, and G. darwinii
Gossypium darwinii
Darwin's cotton is a species of cotton plant which is found only on the Galapagos Islands. Genetic studies indicate that it is most closely related to the native American species Gossypium barbadense, thus it is surmised that a seed arrived from South America on the wind, in the droppings of a...
.
Selected species
Subgenus Gossypium- Gossypium arboreumGossypium arboreumGossypium arboreum, commonly called tree cotton, is a species of cotton native to India and Pakistan and other tropical and subtropical regions of the Old World. There is evidence of its cultivation as long ago as the Harappan civilization of the Indus Valley for the production of cotton textiles...
L. – tree cotton (IndiaIndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and PakistanPakistanPakistan , officially the Islamic Republic of Pakistan is a sovereign state in South Asia. It has a coastline along the Arabian Sea and the Gulf of Oman in the south and is bordered by Afghanistan and Iran in the west, India in the east and China in the far northeast. In the north, Tajikistan...
) - Gossypium herbaceumGossypium herbaceumGossypium herbaceum, also called Levant cotton, is a species of cotton native to the semi-arid regions of sub-Saharan Africa and Arabia where it still grows in the wild as a perennial shrub...
L. – Levant cotton (southern AfricaAfricaAfrica is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
and the Arabian PeninsulaArabian PeninsulaThe Arabian Peninsula is a land mass situated north-east of Africa. Also known as Arabia or the Arabian subcontinent, it is the world's largest peninsula and covers 3,237,500 km2...
)
Subgenus Houzingenia
- Gossypium raimondii Ulbr. – one of the putative progenitor species of tetraploid cotton, alongside G. arboreum
- Gossypium thurberiGossypium thurberiDesert cotton , also known as Arizona wild cotton and Thurber's cotton, is a wild species of cotton native to the Sonoran desert area of northern Mexico and parts of the state of Arizona in the United States....
Tod. – Arizona wild cotton (ArizonaArizonaArizona ; is a state located in the southwestern region of the United States. It is also part of the western United States and the mountain west. The capital and largest city is Phoenix...
and northern MexicoMexicoThe United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
)
Subgenus Karpas
- Gossypium barbadenseGossypium barbadenseGossypium barbadense, also known as extra long staple cotton as it generally has a staple of at least 1 3/8" or longer, is a species of cotton plant. Some types of ELS cotton are American Pima, Egyptian Giza, Indian Suvin, Chinese Xiniang, Sudanese Barakat, and Russian Tonkovoloknistyi...
L. – Creole cotton (tropical South AmericaSouth AmericaSouth America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
) - Gossypium darwiniiGossypium darwiniiDarwin's cotton is a species of cotton plant which is found only on the Galapagos Islands. Genetic studies indicate that it is most closely related to the native American species Gossypium barbadense, thus it is surmised that a seed arrived from South America on the wind, in the droppings of a...
G.Watt – Darwin's cotton (Galápagos IslandsGalápagos IslandsThe Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, west of continental Ecuador, of which they are a part.The Galápagos Islands and its surrounding waters form an Ecuadorian province, a national park, and a...
) - Gossypium hirsutumGossypium hirsutumGossypium hirsutum, known as Upland Cotton or Mexican Cotton, is the most widely planted species of cotton in the United States, constituting some 95% of all cotton production and is native to Central America and possibly Mexico Worldwide, the figure is about 90% of all production for this...
L. – upland cotton (Central AmericaCentral AmericaCentral America is the central geographic region of the Americas. It is the southernmost, isthmian portion of the North American continent, which connects with South America on the southeast. When considered part of the unified continental model, it is considered a subcontinent...
, MexicoMexicoThe United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
, the CaribbeanCaribbeanThe Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
and southern FloridaFloridaFlorida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
) - Gossypium mustelinum Miers ex G.Watt
- Gossypium tomentosumGossypium tomentosumGossypium tomentosum, commonly known as Mao or Hawaiian cotton, is a species of cotton plant that is endemic to the Hawaiian Islands. It inhabits low shrublands at elevations from sea level to . Mao is a shrub that reaches a height of and a diameter of...
Nutt.Thomas NuttallThomas Nuttall was an English botanist and zoologist, who lived and worked in America from 1808 until 1841....
ex Seem – Mao or Hawaiian cotton (HawaiiHawaiiHawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
)
Subgenus Sturtia
- Gossypium australeGossypium australeGossypium australe is an endemic woody shrub, related to cotton, found in north western Australia. Preferring sandy soils near watercourses, it grows to about two or three feet tall....
F.MuellFerdinand von MuellerBaron Sir Ferdinand Jacob Heinrich von Mueller, KCMG was a German-Australian physician, geographer, and most notably, a botanist.-Early life:...
(northwestern AustraliaAustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
) - Gossypium sturtianum J.H. Willis – Sturt's Desert Rose (AustraliaAustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
)
Formerly placed in genus Gossypium
- Gossypioides brevilanatum (Hochr.) J.B.Hutch. (as G. brevilanatum Hochr.)
- Gossypioides kirkii (Mast.) J.B.Hutch. (as Gossypium kirkii Mast.)
- Kokia drynarioidesKokia drynarioidesKokia drynarioides, commonly known as Hawaiian Tree Cotton, is a species of flowering plant in the mallow family, Malvaceae, that is endemic to the Big Island of Hawaii. It inhabits dry forests at elevations of...
(Seem.) Lewton (as G. drynarioides Seem.)
Gossypium genome
A public genome sequencing effort of cotton was initiated in 2007 by a consortium of public researchers. They agreed on a strategy to sequence the genome of cultivated, allotetraploid cotton. "Allotetraploid" means that the genomes of these cotton species comprise two distinct sub-genomes, referred to as the At and Dt (the 't' for tetraploid, to distinguish them from the A and D genomes of the related diploid species). The strategy is to sequence first the D-genome relative of allotetraploid cottons, G. raimondii, a wild South-American (PeruPeru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....
, Ecuador
Ecuador
Ecuador , officially the Republic of Ecuador is a representative democratic republic in South America, bordered by Colombia on the north, Peru on the east and south, and by the Pacific Ocean to the west. It is one of only two countries in South America, along with Chile, that do not have a border...
) cotton species, because of its smaller size due essentially to less repetitive DNA (retrotransposons mainly). It is nearly one-third the number of bases of tetraploid cotton (AD), and each chromosome is only present once. The A genome of G. arboreum, the 'Old-World' cotton species (grown in India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
in particular), would be sequenced next. Its genome is roughly twice the size of G. raimondiis. Once both A and D genome sequences are assembled, then research could begin sequencing the actual genomes of tetraploid cultivated cotton varieties. This strategy is out of necessity; if one were to sequence the tetraploid genome without model diploid genomes, the euchromatic DNA sequences of the AD genomes would co-assemble and the repetitive elements of AD genomes would assembly independently into A and D sequences respectively. Then there would be no way to untangle the mess of AD sequences without comparing them to their diploid counterparts.
The public sector effort continues with the goal to create a high-quality, draft genome sequence from reads generated by all sources. The public-sector effort has generated Sanger reads of BACs, fosmids, and plasmids as well as 454 reads. These later types of reads will be instrumental in assembling an initial draft of the D genome. In 2010, two companies (Monsanto
Monsanto
The Monsanto Company is a US-based multinational agricultural biotechnology corporation. It is the world's leading producer of the herbicide glyphosate, marketed in the "Roundup" brand of herbicides, and in other brands...
and Illumina
Illumina (company)
Illumina, Inc. is a company incorporated in April 1998 that develops, manufactures and markets integrated systems for the analysis of genetic variation and biological function. Using its technologies, the company provides a line of products and services that serve the sequencing, genotyping and...
), completed enough Illumina sequencing to cover the D genome of G. raimondii about 50x. They announced that they would donate their raw reads to the public. This public relations effort gave them some recognition for sequencing the cotton genome. Once the D genome is assembled from all of this raw material, it will undoubtedly assist in the assembly of the AD genomes of cultivated varieties of cotton, but a lot of hard work remains.
Cotton pests and diseases
Pests
- Boll weevilBoll weevilThe boll weevil is a beetle measuring an average length of six millimeters, which feeds on cotton buds and flowers. Thought to be native to Central America, it migrated into the United States from Mexico in the late 19th century and had infested all U.S. cotton-growing areas by the 1920s,...
, Anthonomus grandis - Cotton aphid, Aphis gossypii
- Cotton stainer, Dysdercus Koenigii
- Cotton bollwormCotton bollwormCotton bollworm may refer to:* Helicoverpa zea* Helicoverpa armigera, the American bollworm or tomato grub- See also :* Bollworm...
, Helicoverpa armigera, and native budworm, Helicoverpa punctigera, are caterpillars that damage cotton crops. - Some other LepidopteraLepidopteraLepidoptera is a large order of insects that includes moths and butterflies . It is one of the most widespread and widely recognizable insect orders in the world, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
(butterflyButterflyA butterfly is a mainly day-flying insect of the order Lepidoptera, which includes the butterflies and moths. Like other holometabolous insects, the butterfly's life cycle consists of four parts: egg, larva, pupa and adult. Most species are diurnal. Butterflies have large, often brightly coloured...
and mothMothA moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...
) larvaLarvaA larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e also feed on cotton - see list of Lepidoptera that feed on cotton plants. - Green mirid (Creontiades dilutus), a sucking insect
- Spider miteSpider miteSpider mites are members of the Acari family Tetranychidae, which includes about 1,200 species. They generally live on the under sides of leaves of plants, where they may spin protective silk webs, and they can cause damage by puncturing the plant cells to feed...
s, Tetranychus urticae, T. ludeni and T. lambi - ThripsThripsThrips are tiny, slender insects with fringed wings . Other common names for thrips include thunderflies, thunderbugs, storm flies, thunderblights, and corn lice...
, Thrips tabaci and Frankliniella schultzei
Diseases
- Alternaria leaf spotAlternariaAlternaria is a genus of ascomycete fungi. Alternaria species are known as major plant pathogens. They are also common allergens in humans, growing indoors and causing hay fever or hypersensitivity reactions that sometimes lead to asthma...
, caused by Alternaria macrospora and Alternaria alternataAlternaria alternataAlternaria alternata has been recorded causing leaf spot and other diseases on over 380 host species. It is opportunistic pathogen on numerous hosts causing leaf spots, rots and blights on many plant parts... - Anthracnose boll rot, caused by Colletotrichum gossypiiColletotrichum gossypiiColletotrichum gossypii is a plant pathogen. This fungus is related to cotton plants where causes anthracnose. It reproduction in the plants is asexually. The conidia have only one nucleus. Before conidia germination fusion by mean of conidial anastomosis tube could happen. The conidia could...
- Black root rotThielaviopsisThielaviopsis is a small genus of fungi in the order Microascales. The genus includes several important agricultural pathogens. The most widespread is T. basicola, the causal agent in several root rot diseases of economically important crop species including cotton and a variety of vegetables...
, caused by the fungus Thielaviopsis basicolaThielaviopsis basicolaThielaviopsis basicola is a plant pathogen.- External links :* *... - Blight caused by Xanthomonas campestris pv. malvacearum
- Fusarium boll rot caused by Fusarium spp.
- Phytophthora boll rot, caused by Phytophthora nicotianae var. parasitica
- Sclerotinia boll rot, caused by the fungus Sclerotinia sclerotiorumSclerotinia sclerotiorumSclerotinia sclerotiorum is a plant pathogenic fungus and can cause a disease called white mold if conditions are correct. S. sclerotiorum can also be known as cottony rot, watery soft rot, stem rot, drop, crown rot and blossom blight...
- StigmatomycosisStigmatomycosisThe term Stigmatomycosis is the general name for a fungal disease that occurs in a number of crops, such as cotton, soybean, pecan, pomegranate, citrus, and pistachio. It has been reported on pistachio in Greece, Iran, Russia, and is frequently a problem in California pistachio orchards severely...
, caused by the fungi Ashbya gossypiiAshbya gossypiiAshbya gossypii is a filamentous fungus or mold closely related to yeast, but growing exclusively in a filamentous way. It was originally isolated from cotton as a pathogen causing stigmatomycosis by Ashby and Novell in 1926...
, Eremothecium coryli, (Nematospora coryli) and Aureobasidium pullulansAureobasidium pullulansAureobasidium pullulans is a ubiquitous yeast-like fungus that can be found in different environments . It is well known as a naturally occurring epiphyte or endophyte of a wide range of plant species without causing any symptoms of disease.A...