Gossypium is a
genusIn biology, a genus is a taxonomic unit used in the classification of living and fossil organisms. The term comes from Latin genus "descent, family, type, gender" , cognate with – genos, "race, stock, kin" ..In addition, genus is a taxonomic rank in the hierarchy In biology, a genus (plural:...
of 39-40 species of
shrubA shrub or bush is a horticultural rather than strictly botanical category of woody plant, distinguished from a tree by its multiple stems and lower height, usually less than 5-6 m tall. A large number of plants can be either shrubs or trees, depending on the growing conditions they experience...
s in the
mallowMalva 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...
family,
MalvaceaeMalvaceae, 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 and cacao...
, native to the tropical and subtropical regions of both the
Old WorldThe Old World consists of those parts of Earth known to Europeans, Asians, and Africans in the 15th century.-Regions:The Old World includes Europe, Asia, and Africa , plus surrounding islands...
and the
New WorldThe New World is one of the names used for the non-Afro-Eurasian parts of the Earth, specifically the Americas and possibly Australia. When the term originated in the late 15th century, the Americas were new to the Europeans, who previously thought of the world as consisting only of Europe, Asia,...
. The cotton plants, sources of
commercial cottonCotton is a soft, staple fiber that grows in a form known as a boll around the seeds of the cotton plant, a shrub native to tropical and subtropical regions around the world, including the Americas, India and Africa. The fiber most often is spun into yarn or thread and used to make a soft,...
fabric, are included in this genus.
Cotton shrubs can grow up to high. The leaves are broad and lobed, with three to five (or rarely seven) lobes. The seeds are contained in a
capsuleIn botany a capsule is a type of simple, dry fruit produced by many species of flowering plants. A capsule is a dehiscent structure composed of two or more carpels, that, at maturity, split apart to release the seeds within...
called a
boll, each seed surrounded by fibres of two types.
These fibres are the commercially interesting part of the plant and they are removed 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 including the eponymous Lint.
Commercial species of cotton plant are
G. hirsutum (90% of world production),
G. barbadense (8%),
G. arboreum and
G. herbaceum (together, 2%). While cotton fibers occur naturally in colors of white, brown, and green, fears of contaminating the genetics of white cotton has led many cotton-growing locations to ban growing of coloured cotton varieties.
Species of Gossypium
Commercial cotton species
Commercial
cottonCotton is a soft, staple fiber that grows in a form known as a boll around the seeds of the cotton plant, a shrub native to tropical and subtropical regions around the world, including the Americas, India and Africa. The fiber most often is spun into yarn or thread and used to make a soft,...
fibres, used to manufacture cloth, are derived from the fruit of the cotton plant. The following species are grown commercially:
- 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 2000 BC by the Harappan civilization of the Indus Valley for the production of...
L.Carl Linnaeus was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature...
– Tree cotton, native to IndiaIndia, 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, and the most populous democracy in the world. Bounded by the Indian Ocean on the south, the Arabian Sea on the west, and the Bay of Bengal...
and PakistanPakistan , officially the Islamic Republic of Pakistan, is a country located at the crossroads of South Asia, the Middle East, and Central Asia...
.
- Gossypium barbadense
Pima cotton , also known as Extra Long Staple, South American, Creole, Sea Island cotton, Egyptian, Algodon pais, and West Indische katoen, is a species of cotton plant which is widely cultivated though it originated in Peru. It is a tropical perennial plant that produces yellow flowers and has...
L. – known as American Pima, Creole, Egyptian, or Sea island cotton, native to tropical South AmericaSouth America is the southern continent of the Americas, situated entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere...
.
- 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. It was probably first cultivated in Ethiopia or southern Arabia and from there, cultivation spread to...
L. – Levant cotton, native to southern AfricaAfrica 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. With a billion people in 61 territories, it accounts for about 14.8% of the...
and Arabian PeninsulaThe Arabian Peninsula , Arabia, Arabistan, and the Arabian subcontinent is a peninsula in Southwest Asia at the junction of Africa and Asia...
.
- 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. Worldwide, the figure is about 90% of all production for this species.Archeological evidence from the Tehuacan Valley in...
L. – Upland cotton, native to Central AmericaManagua
Guatemala City
San Salvador
San Pedro Sula
Panama City
San José, Costa Rica
Santa Ana, El Salvador
León
San Miguel|-|}...
, MexicoThe 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 CaribbeanThe Caribbean is a region consisting of the Caribbean Sea, its islands , and the surrounding coasts...
and southern FloridaFlorida is a state located in the southeastern region of the United States, bordering Alabama to the northwest and Georgia to the north. It was the 27th state admitted to the United States...
- most commonly grown species in the world.
Non-commercial species
- Gossypium australe
Gossypium 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.MuellBaron Sir Ferdinand Jacob Heinrich von Mueller, KCMG was a German-Australian physician, geographer, and most notably, a botanist.-Early life:...
– Endemic to north-western AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the continental mainland , the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans...
- 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...
- Darwin's cotton, found only on the Galapagos IslandsThe Galápagos Islands are an archipelago of volcanic islands distributed around the equator in the Pacific Ocean, 972 km west of continental Ecuador...
- Gossypium sturtianum J.H. Willis
James Hamlyn Willis was an Australian botanist.-Early life and education:Willis was born in Stanley in northwest Tasmania. During his childhood he avidly explored the coastline and nearby heathlands and bush, developing an interest in nature...
– Sturt's Desert Rose, native to AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the continental mainland , the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans...
.
- Gossypium thurberi
Desert 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, native to ArizonaThe State of Arizona is a state located in the southwestern region of the United States. The capital and largest city is Phoenix. The second largest city is Tucson, followed in size by the four Phoenix metropolitan area cities of Mesa, Glendale, Chandler, and Scottsdale.Arizona was the 48th and...
and northern MexicoThe 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...
.
- Gossypium tomentosum
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 Nuttall was an English botanist and zoologist, who lived and worked in America from 1808 until 1841....
ex Seem – Ma‘o or Hawaiian cotton, endemic to the Hawaiian IslandsThe Hawaiian Islands are an archipelago of 19 islands and atolls, numerous smaller islets, and undersea seamounts in the North Pacific Ocean, extending some 1,500 miles from the island of Hawaii in the south to northernmost Kure Atoll. Excluding Midway, which is an unincorporated territory of the...
.
- Gossypium raimondii one of the putative progenitor species of tetraploid cotton alongside Gossypium arboreum.
Many varieties of cotton have been developed by selective breeding and hybridization of the above species. Experiments are ongoing to cross-breed various desirable traits of wild cotton species into the principal commercial species, such as resistance to insects, disease and drought-tolerance.
Most wild cottons are
diploidPloidy is the number of complete sets of chromosomes in a biological cell. In humans, the somatic cells that compose the body are diploid , but sex cells are haploid...
, but there is a group of five species from America and Pacific islands which are tetraploid, apprently due a single hybridization 0.5 to 2 million years ago. The tetraploid species are
G. 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. Worldwide, the figure is about 90% of all production for this species.Archeological evidence from the Tehuacan Valley in...
,
G. tomentosumMao 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. barbadensePima cotton , also known as Extra Long Staple, South American, Creole, Sea Island cotton, Egyptian, Algodon pais, and West Indische katoen, is a species of cotton plant which is widely cultivated though it originated in Peru. It is a tropical perennial plant that produces yellow flowers and has...
, and
G. 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...
.
Cotton pests and diseases
Pests
- Boll weevil
The 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 US from Mexico in the late 19th century and had infested all US cotton-growing areas by the 1920s, devastating the...
, Anthonomus grandis
- Cotton aphid, Aphis gossypii
- Cotton stainer, Dysdercus Koenigii
- Cotton bollworm
Cotton bollworm may refer to:* Helicoverpa zea, the American cotton bollworm or corn earworm* Helicoverpa armigera, the African cotton bollworm or tomato grub- See also :* Bollworm...
, Helicoverpa armigera and native budworm Helicoverpa punctigera are caterpillars that damage cotton crops.
- Some other Lepidoptera
Lepidoptera is an order of insects that includes moths and butterflies. It is one of the most speciose orders in the class Insecta, encompassing moths and the three superfamilies of butterflies, skipper butterflies, and moth-butterflies...
(butterflyA butterfly is an insect of the order Lepidoptera. Like all Lepidoptera, butterflies are notable for their unusual life cycle with a larval caterpillar stage, an inactive pupal stage, and a spectacular metamorphosis into a familiar and colourful winged adult form. Most species are day-flying so...
and mothA moth is an insect closely related to the butterfly, both being of the order Lepidoptera. The differences between butterflies and moths are more than just taxonomy. Sometimes the names "Rhopalocera" and "Heterocera" are used to formalize the popular distinction...
) larvaA larva is a young form of animal with indirect development, going through or undergoing metamorphosis ....
e also feed on cotton - see list of Lepidoptera that feed on cotton plants.
- Green mirid (Creontiades dilutus), a sucking insect
- Spider mite
Spider mites are members of the Acari family Tetranychidae, which includes about 1600 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
- Thrips
Thrips are tiny, slender insects with fringed wings . Other common names for thrips include thunderflies, thunderbugs, storm flies, and corn lice...
, Thrips tabaci and Frankliniella schultzei
Diseases
- Alternaria leaf spot
Alternaria 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 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 gossypii
Colletotrichum gossypii is a plant pathogen. This fungi 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 rot
Thielaviopsis 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 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 fungus Sclerotinia sclerotiorum
Sclerotinia sclerotiorum is a plant pathogen. It has a wide range of hosts and is characterized by white fuzzy growths on the plant it infects.- External links :**...
- Stigmatomycosis
The 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 gossypii Ashbya 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 pullulans is a plant pathogen, causing stigmatomycosis on cotton. It can be cultivated on potato dextrose agar where it produces smooth, faint pink yeast-like colonies that are covered with a slimy mass of spores. Older colonies change to black due to chlamydospore production...
External links