Gossypium L. is a genus of approximately 50–55 species of shrubs and small trees in the mallow family (Malvaceae), universally known as cotton. Plants typically grow 1–2 meters tall with broad, palmately lobed leaves bearing 3–5 lobes, and produce distinctive seed capsules called bolls. Inside each boll, seeds are enveloped by soft fibers — the "staple" lint used in textiles and the shorter "linters" used in industrial applications. Natural fiber colors range from white and cream to brown and green.
The genus originated an estimated 5–10 million years ago and is native to tropical and subtropical regions spanning both the Old World and New World. Most species are diploid; five American and Pacific island species, including the dominant commercial species G. hirsutum, are allotetraploids that arose from a hybridization event approximately 1.5–2 million years ago.
Cotton is one of humanity's most economically significant plants. Cotton fiber accounts for roughly 80% of natural fiber produced worldwide, and the seeds yield an edible oil and high-protein meal. Of the approximately 55 species, only four are cultivated commercially: G. hirsutum (upland cotton, ~90–97% of global production), G. barbadense (Sea Island or Pima cotton, prized for extra-long staple), G. arboreum, and G. herbaceum. The remaining species are wild and of scientific, ecological, and breeding interest.
Cultivation has a documented history of at least 5,000 years in Mexico, with parallel independent domestications in South Asia and East Africa. Today cotton is grown in more than 100 countries and is a major cash crop across South Asia, the Americas, and sub-Saharan Africa. Research into genomics — particularly sequencing of the G. raimondii D-genome and G. arboreum A-genome — is underway to improve fiber quality, disease resistance, and drought tolerance in commercial cultivars.
Etymology
The genus name Gossypium is derived from the Arabic word goz, meaning a soft substance — a direct reference to the soft fibers that envelop the seeds inside the cotton boll.
Distribution
Gossypium is native to seasonally dry tropical and subtropical regions across both hemispheres, with wild species found in Australia, southern Africa, the Arabian Peninsula, the Indian subcontinent, Mexico, Central America, the Caribbean, and South America (including the Galápagos Islands). The genus is particularly diverse in Australia, where species such as G. sturtianum (Sturt's desert rose) occupy arid inland habitats.
Commercially cultivated species have been introduced to over 100 countries beyond their native ranges, extending from the southern United States and Central Asia to sub-Saharan Africa and Southeast Asia. India currently leads global cotton production, followed by China, several African nations, and the USA.
Ecology
Wild Gossypium species occupy arid to semiarid tropical and subtropical habitats, often on well-drained or rocky soils. Cultivated cotton (G. hirsutum) is a fast-growing shrub adapted to full sun with optimal growth at 22–36°C and annual rainfall of 750–1,200 mm. The plants tolerate a wide soil pH range (5–9.5) and moderate salinity.
Cotton is subject to a wide range of pests and diseases in agricultural settings. Major pests include the boll weevil, cotton aphid, cotton stainer, cotton bollworm, budworms, spider mites, and thrips. Significant diseases include bacterial blight, Fusarium and Phytophthora boll rots, Alternaria leaf spot, and anthracnose boll rot.
Cultivation
Cotton is grown as an annual crop in most commercial systems despite being a perennial shrub in its native environment. Commercial cultivation requires full sun, warm temperatures (22–36°C optimal), and well-drained soils tolerant of a wide pH range (5–9.5). Annual rainfall of 750–1,200 mm is preferred, though irrigation is widely used.
Plants are typically spaced 18–30 inches apart in rows 5 feet apart. In temperate climates (USDA zones 5–7), cotton can be started indoors like tomatoes; in zones 8–10 it is direct-sown after the last frost. The crop matures in 150–220 days when grown as an annual; perennial cultivation in tropical regions can yield superior fiber quality.
G. hirsutum dominates global production at approximately 90–97% of the total. G. barbadense (Pima/Sea Island cotton) contributes 1–2% and is valued for its extra-long staple fiber. G. arboreum and G. herbaceum together account for roughly 1% of world production.
Propagation
Cotton is propagated almost exclusively from seed. Seeds germinate in 7–21 days at approximately 21°C (70°F). In frost-prone climates (USDA zones 5–7), seeds are started indoors 4–6 weeks before the last frost date, analogous to tomato propagation. In warmer zones (8–10), direct sowing after the last frost is standard. Glandless cultivars (selected for reduced gossypol content) are recommended when seed is intended for food use.
Cultural Uses
Cotton fiber is the genus's defining economic contribution, accounting for approximately 80% of all natural fiber produced globally. Fiber uses span clothing and household textiles, medical and cosmetic cotton wool, rubber-tyre fabrics, stuffing materials, surgical dressings, twine, rope, and paper (notably for banknotes and archival documents).
Beyond fiber, cottonseed yields a high-protein meal (up to 40% protein) used as livestock feed and — in glandless varieties free of gossypol — as a food source for humans in the form of roasted seeds, seed flour, and cooking oil. Cottonseed oil is also pressed for soap, lubricants, and protective coatings. Seed hulls and plant stalks are used as fuel; spent seed cake after oil extraction serves as an organic fertilizer.
Traditional medicinal uses include topical application of boiled leaves for skin conditions in children.
Cotton cultivation has been deeply intertwined with global economic history. India was the first country to produce it at scale, and the American cotton economy from the late 18th century onward was driven largely by enslaved labor, accelerated by the invention of the cotton gin in 1793. Today the crop underpins the livelihoods of hundreds of millions of farmers and textile workers across more than 100 countries.
History
Cotton cultivation has independent origins in at least three regions. Gossypium hirsutum was first cultivated approximately 5,000 years ago in Mexico; G. barbadense was independently domesticated in coastal Peru and Ecuador; and G. arboreum and G. herbaceum were brought into cultivation in South Asia and East Africa respectively. Archaeological evidence of cotton textiles has been found at sites in the Indus Valley civilization and in pre-Columbian sites throughout the Americas.
India dominated global cotton production for centuries, supplying fiber to Asian and later European markets. The Industrial Revolution in Britain greatly expanded demand, and the invention of Eli Whitney's cotton gin in 1793 transformed the American South, making upland cotton (G. hirsutum) the region's chief cash crop — a transition directly linked to the dramatic expansion of enslaved labor in the antebellum United States.
In the 20th century, plant breeding and the Green Revolution shifted production patterns globally. Today India and China are the leading producers, and genomic research — including sequencing of G. raimondii and G. arboreum — is advancing efforts to improve fiber yield, quality, and pest resistance in commercial varieties.
Taxonomy Notes
Gossypium L. was described by Linnaeus and belongs to the tribe Gossypieae within the family Malvaceae. It is the largest genus in its tribe and contains approximately 50–55 accepted species, with new species continuing to be described. GBIF records approximately 113 descendant taxa (including infraspecific ranks).
Most wild species are diploid. The five allotetraploid species — G. hirsutum, G. barbadense, G. tomentosum, G. mustelinum, and G. darwinii — share a common allotetraploid origin from a hybridization event between an Old World A-genome diploid and a New World D-genome diploid, estimated at 1.5–2 million years ago. Understanding the genomic architecture of this polyploidization is a focus of modern cotton genomics. Genome sequencing of G. raimondii (D-genome donor) and G. arboreum (A-genome donor) was initiated in 2007 as a stepping stone to sequencing the complex tetraploid cultivars.
