Kamis, 29 Januari 2009

COTTON

Cotton is a soft, staple fiber that grows in a form known as a boll around the seeds of the cotton plant (Gossypium sp.), 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, breathable textile, which is the most widely used natural-fiber cloth in clothing today. The English name, which began to be used circa 1400, derives from the Arabic (al) qutn قُطْن, meaning cotton.[1]


History

Cotton plants as imagined and drawn by John Mandeville in the fourteenth century

Cotton was cultivated by the inhabitants of the Indus Valley Civilization by the 5th millennium BCE - 4th millennium BCE.[2] The Indus cotton industry was well developed and some methods used in cotton spinning and fabrication continued to be used until the modern Industrialization of India.[3] Well before the Common Era the use of cotton textiles had spread from India to the Mediterranean and beyond.[4]

According to The Columbia Encyclopedia, Sixth Edition:[5]

"Cotton has been spun, woven, and dyed since prehistoric times. It clothed the people of ancient India, Egypt, and China. Hundreds of years before the Christian era cotton textiles were woven in India with matchless skill, and their use spread to the Mediterranean countries. In the 1st cent. Arab traders brought fine muslin and calico to Italy and Spain. The Moors introduced the cultivation of cotton into Spain in the 9th cent. Fustians and dimities were woven there and in the 14th cent. in Venice and Milan, at first with a linen warp. Little cotton cloth was imported to England before the 15th cent., although small amounts were obtained chiefly for candlewicks. By the 17th cent. the East India Company was bringing rare fabrics from India. Native Americans skillfully spun and wove cotton into fine garments and dyed tapestries. Cotton fabrics found in Peruvian tombs are said to belong to a pre-Inca culture. In color and texture the ancient Peruvian and Mexican textiles resemble those found in Egyptian tombs."

The earliest cultivation of cotton discovered thus far in the Americas occurred in Mexico, some 5,000 years ago. The indigenous species was Gossypium hirsutum which is today the most widely planted species of cotton in the world, constituting about 90% of all production worldwide. The greatest diversity of wild cotton species is found in Mexico, followed by Australia and Africa.[6]

In Peru, cultivation of the indigenous cotton species Gossypium barbadense was the backbone of the development of coastal cultures such as the Norte Chico, Moche and Nazca. Cotton was grown upriver, made into nets and traded with fishing villages along the coast for large supplies of fish. The Spanish who came to Mexico in the early 1500s found the people growing cotton and wearing clothing made of it.

During the late medieval period, cotton became known as an imported fiber in northern Europe, without any knowledge of how it was derived, other than that it was a plant; noting its similarities to wool, people in the region could only imagine that cotton must be produced by plant-borne sheep. John Mandeville, writing in 1350, stated as fact the now-preposterous belief: "There grew there [India] a wonderful tree which bore tiny lambs on the endes of its branches. These branches were so pliable that they bent down to allow the lambs to feed when they are hungrie [sic]." (See Vegetable Lamb of Tartary.) This aspect is retained in the name for cotton in many European languages, such as German Baumwolle, which translates as "tree wool" (Baum means "tree"; Wolle means "wool"). By the end of the 16th century, cotton was cultivated throughout the warmer regions in Asia and the Americas.

India's cotton-processing sector gradually declined during British expansion in India and the establishment of colonial rule during the late 18th and early 19th centuries. This was largely due to the East India Company's exposing of India to foreign competition, which made cotton processing and manufacturing workshops in India uncompetitive. Indian markets increasingly supplied only raw cotton and were obliged to purchase manufactured textiles from Britain.

The advent of the Industrial Revolution in Britain provided a great boost to cotton manufacture, as textiles emerged as Britain's leading export. In 1738 Lewis Paul and John Wyatt, of Birmingham, England, patented the Roller Spinning machine, and the flyer-and-bobbin system for drawing cotton to a more even thickness using two sets of rollers that traveled at different speeds. Later, the invention of the spinning jenny in 1764 and Richard Arkwright's spinning frame (based on the Roller Spinning Machine) in 1769 enabled British weavers to produce cotton yarn and cloth at much higher rates. From the late eighteenth century onwards, the British city of Manchester acquired the nickname "cottonopolis" due to the cotton industry's omnipresence within the city, and Manchester's role as the heart of the global cotton trade. Production capacity was further improved by the invention of the cotton gin by Eli Whitney in 1793. Improving technology and increasing control of world markets allowed British traders to develop a commercial chain in which raw cotton fibers were (at first) purchased from colonial plantations, processed into cotton cloth in the mills of Lancashire, and then re-exported on British ships to captive colonial markets in West Africa, India, and China (via Shanghai and Hong Kong).

By the 1840s, India was no longer capable of supplying the vast quantities of cotton fibers needed by mechanized British factories, while shipping bulky, low-price cotton from India to Britain was time-consuming and expensive. This, coupled with the emergence of American cotton as a superior type (due to the longer, stronger fibers of the two domesticated native American species, Gossypium hirsutum and Gossypium barbadense), encouraged British traders to purchase cotton from plantations in the United States and the Caribbean. This was also much cheaper as it was produced by unpaid slaves. By the mid 19th century, "King Cotton" had become the backbone of the southern American economy. In the United States, cultivating and harvesting cotton became the leading occupation of slaves.

During the American Civil War, American cotton exports slumped due to a Union blockade on Southern ports, also because of a strategic decision by the Confederate Government to cut exports, hoping to force Britain to recognize the Confederacy or enter the war, prompting the main purchasers of cotton, Britain and France, to turn to Egyptian cotton. British and French traders invested heavily in cotton plantations and the Egyptian government of Viceroy Isma'il took out substantial loans from European bankers and stock exchanges. After the American Civil War ended in 1865, British and French traders abandoned Egyptian cotton and returned to cheap American exports, sending Egypt into a deficit spiral that led to the country declaring bankruptcy in 1876, a key factor behind Egypt's annexation by the British Empire in 1882.

Picking cotton in Oklahoma, USA, in the 1890s

During this time cotton cultivation in the British Empire, especially India, greatly increased to replace the lost production of the American South. Through tariffs and other restrictions the British government discouraged the production of cotton cloth in India; rather the raw fiber was sent to England for processing. The Indian patriot Mahatma Gandhi described the process:

  1. English people buy Indian cotton in the field, picked by Indian labor at seven cents a day, through an optional monopoly.
  2. This cotton is shipped on British bottoms, a three-week journey across the Indian Ocean, down the Red Sea, across the Mediterranean, through Gibraltar, across the Bay of Biscay and the Atlantic Ocean to London. One hundred per cent profit on this freight is regarded as small.
  3. The cotton is turned into cloth in Lancashire. You pay shilling wages instead of Indian pennies to your workers. The English worker not only has the advantage of better wages, but the steel companies of England get the profit of building the factories and machines. Wages; profits; all these are spent in England.
  4. The finished product is sent back to India at European shipping rates, once again on British ships. The captains, officers, sailors of these ships, whose wages must be paid, are English. The only Indians who profit are a few lascars who do the dirty work on the boats for a few cents a day.
  5. The cloth is finally sold back to the kings and landlords of India who got the money to buy this expensive cloth out of the poor peasants of India who worked at seven cents a day. (Fisher 1932 pp 154-156)
Prisoners farming cotton under trusty system - 1911

In the United States, Southern cotton provided capital for the continuing development of the North. The cotton produced by enslaved African Americans not only helped the South but also enriched Northern merchants. Much of the Southern cotton was transshipped through the northern ports.

Cotton remained a key crop in the southern economy after emancipation and the end of the civil war in 1865. Across the South, sharecropping evolved, in which free black farmers worked on white-owned cotton plantations in return for a share of the profits. Cotton plantations required vast labor forces to hand-pick cotton, and it was not until the 1950s that reliable harvesting machinery was introduced into the South (prior to this, cotton-harvesting machinery had been too clumsy to pick cotton without shredding the fibers). During the early twentieth century, employment in the cotton industry fell as machines began to replace laborers, and as the South's rural labor force dwindled during the First and Second World Wars. Today, cotton remains a major export of the southern United States, and a majority of the world's annual cotton crop is of the long-staple American variety.[7]

Tangüis cotton

Main article: Fermín Tangüis
Fermin Tangüis poses with an example of the "Tangüis cotton"

In 1901, Peru's cotton industry suffered because of a fungus plague caused by a plant disease known as "Cotton wilt" and " "Fusarium wilt" (Fusarium vasinfectum).[8] The plant disease, which spread throughout Peru, entered the plant by its roots and worked it's way up the stem until the plant was completely dried up. Fermín Tangüis a Puerto Rican agriculturist who lived in Peru, studied some species of the plant that were affected by the disease to a lesser extent and experimented in germination with the seeds of various cotton plants. In 1911, after 10 years of experimenting and failures, Tangüis was able to develop a seed which produced a superior cotton plant resistant to the disease. The seeds produced a plant that had a 40% longer (between 29 mm and 33 mm) and thicker fiber that did not break easily and required little water.[9] The Tangüis cotton, as it became known, is the variety which is preferred by the Peruvian national textile industry. It constituted 75 percent of all the Peruvian cotton production, both for domestic use and apparel exports. The Tangüis cotton crop was estimated at 225,000 bales that year.[10]

Cultivation

Harvested cotton in Tennessee (2006)
Cotton plowing in Togo, 1928

Successful cultivation of cotton requires a long frost-free period, plenty of sunshine, and a moderate rainfall, usually from 600 to 1200mm (24 to 48 inches). Soils usually need to be fairly heavy, although the level of nutrients does not need to be exceptional. In general, these conditions are met within the seasonally dry tropics and subtropics in the Northern and Southern hemispheres, but a large proportion of the cotton grown today is cultivated in areas with less rainfall that obtain the water from irrigation. Production of the crop for a given year usually starts soon after harvesting the preceding autumn. Planting time in spring in the Northern hemisphere varies from the beginning of February to the beginning of June. The area of the United States known as the South Plains is the largest contiguous cotton-growing region in the world. It is heavily dependent on irrigation water drawn from the Ogallala Aquifer.

Cotton is a thirsty crop, and as water resources get tighter around the world, economies that rely on it face difficulties and conflict, as well as potential environmental problems. For example, cotton has led to desertification in areas of Uzbekistan, where it is a major export. In the days of the Soviet Union, the Aral Sea was tapped for agricultural irrigation, largely of cotton, and now salination is widespread.

Genetically modified cotton

Genetically modified (GM) cotton was developed to reduce the heavy reliance on pesticides. The bacterium Bacillus thuringiensis naturally produces a chemical harmful only to a small fraction of insects, most notably the larvae of moths and butterflies, beetles, and flies, and harmless to other forms of life. The gene coding for BT toxin has been inserted into cotton, causing cotton to produce this natural insecticide in its tissues. In many regions the main pests in commercial cotton are lepidopteran larvae, which are killed by the BT protein in the transgenic cotton that they eat. This eliminates the need to use large amounts of broad-spectrum insecticides to kill lepidopteran pests (some of which have developed pyrethroid resistance). This spares natural insect predators in the farm ecology and further contributes to non-insecticide pest management.

BT cotton is ineffective against many cotton pests, however, such as plant bugs, stink bugs, aphids, etc.; depending on circumstances it may still be desirable to use insecticides against these.

Genetically modified cotton is widely used throughout the world. However, researchers have recently published the first documented case of in-field pest resistance to GM cotton.[11] The International Service for the Acquisition of Agri-biotech Applications (ISAAA) said that, worldwide, GM cotton was planted on an area of 67,000 km² in 2002. This is 20% of the worldwide total area planted in cotton. The U.S. cotton crop was 73% GM in 2003.

The initial introduction of GM cotton proved to be a commercial and ecological disaster in Australia - the yields were far lower than predicted, and the cotton plants were cross-pollinated with other varieties of cotton. However, the introduction of a second variety of GM cotton led to 15% of Australian cotton being GM in 2003. 80% of the crop was genetically modified in 2004, when the original GM variety was banned.

Cotton has also been genetically modified for resistance to glyphosate (marketed as Roundup in the USA), an inexpensive and highly effective but broad-spectrum herbicide, during its early growth. This allows glyphosate to be used for weed control during the early growing season.

GM cotton acreage in India continues to grow at a rapid rate increasing from 50,000 hectares in 2002 to 3.8 million hectares in 2006. The total cotton area in India is about 9.0 million hectares (the largest in the world or, about 25% of world cotton area) so GM cotton is now grown on 42% of the cotton area. This makes India the country with the largest area of GM cotton in the world, surpassing China (3.5 million hectares in 2006). The major reasons for this increase is a combination of increased farm income ($225/ha) and a reduction in pesticide use to control the Cotton Bollworm.

Cotton has gossypol, a toxin that makes it inedible. However, scientists have silenced the gene that produces the toxin, making it a potential food crop.

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