Angiosperms (Flowering Plants) • Earth.com

American cotton

(Gossypium barbadense)

galery
en

Description

Gossypium barbadense is one of several species of cotton. It is in the mallow family. It has been cultivated since antiquity, but has been especially prized since a form with particularly long fibers was developed in the 1800s. Other names associated with this species include sea island, Egyptian, Pima, and extra-long staple (ELS) cotton. The species is a tropical, frost-sensitive perennial that produces yellow flowers and has black seeds. It grows as a bush or small tree and yields cotton with unusually long, silky fibers. G. barbadense originated in southwest Ecuador and northwest Peru. It is now cultivated around the world, including China, Egypt, Sudan, India, Australia, Peru, Israel, the southwestern United States, Tajikistan, Turkmenistan, and Uzbekistan. G. barbadense accounts for about 5% of the world's cotton production. G. barbadense, like other cottons, forms a small bush in its first year. In cultivation, it is treated as an annual. If allowed to, it can grow into a large bush or even a small tree of height 1–3 m. Leaves are mostly 8–20 cm long, with 3-7 lobes. One distinction between G. barbadense and the more commonly cultivated G. hirsutum is that G. barbadense has three to five lobes whereas G. hirsutum has only three. The lobes of G. barbadense's are also more deeply cut, about ⅔ the length of the leaf, as opposed to ½ for G. hirsutum. Cotton flowers are showy, with five petals that open only partially. The petals are up to 8 cm long, usually yellow. The petals of sea island cultivars typically are creamy yellow with a red spot at the base, and as they wither, they turn rose pink. Like other members of the mallow family, the flowers have many stamens, which are merged to form a cylinder around the style. The seeds and fiber form in a capsule called a "bole". Each bole is divided into three parts, each of which produce 5-8 seeds. The seeds are 8-10 mm long. Thousands of years of cultivation have dramatically changed the fiber in cotton plants. Wild cottons have very little fiber, so little it might not be noticed. The fiber emanates from each seed. The purpose of the fiber to wild plants is unknown. Domesticated cottons have much more fiber. Besides for the more obvious long fibers, domesticated cotton seeds have short fibers called "linters". Some cultivars of G. barbadense have so few of these short hairs they are often called "lintless". They can also be called "smooth-seeded" as opposed to "fuzzy-seeded" G. hirsutum.

Taxonomic tree:

Domain:
Kingdom: Plantae
Phylum: Magnoliophyta
Class: Magnoliopsida
Order:Malvales
Family:Malvaceae
Genus:Gossypium
News coming your way
The biggest news about our planet delivered to you each day