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 (GM) cotton was developed to reduce the heavy reliance on pesticides. Genetically modified cotton is widely used throughout the world with claims of requiring up to 80% less pesticide than ordinary cotton as typically grown commercially. 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.
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 in a potential food crop.[12]
Organic cotton is cotton that is grown without insecticide or pesticide. Worldwide, cotton is a pesticide-intensive crop, using approximately 25% of the world's insecticides and 10% of the world's pesticides.[13] According to the World Health Organization (WHO), 20,000 deaths occur each year from pesticide poisoning in developing countries, many of these from cotton farming. Organic agriculture uses methods that are ecological, economical, and socially sustainable and denies the use of agrochemicals and artificial fertilizers. Instead, organic agriculture uses crop rotation, the growing of different crops than cotton in alternative years. The use of insecticides is prohibited; organic agriculture uses natural enemies to suppress harmful insects. The production of organic cotton is more expensive than the production of conventional cotton. Although toxic pollution from synthetic chemicals is eliminated, other pollution-like problems may remain, particularly run-off. Organic cotton is produced in organic agricultural systems that produce food and fiber according to clearly established standards. Organic agriculture prohibits the use of toxic and persistent chemical pesticides and fertilizers, as well as genetically modified organisms. It seeks to build biologically diverse agricultural systems, replenish and maintain soil fertility, and promote a healthy environment.
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 (GM) cotton was developed to reduce the heavy reliance on pesticides. Genetically modified cotton is widely used throughout the world with claims of requiring up to 80% less pesticide than ordinary cotton as typically grown commercially. 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.
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 in a potential food crop.[12]
Organic cotton is cotton that is grown without insecticide or pesticide. Worldwide, cotton is a pesticide-intensive crop, using approximately 25% of the world's insecticides and 10% of the world's pesticides.[13] According to the World Health Organization (WHO), 20,000 deaths occur each year from pesticide poisoning in developing countries, many of these from cotton farming. Organic agriculture uses methods that are ecological, economical, and socially sustainable and denies the use of agrochemicals and artificial fertilizers. Instead, organic agriculture uses crop rotation, the growing of different crops than cotton in alternative years. The use of insecticides is prohibited; organic agriculture uses natural enemies to suppress harmful insects. The production of organic cotton is more expensive than the production of conventional cotton. Although toxic pollution from synthetic chemicals is eliminated, other pollution-like problems may remain, particularly run-off. Organic cotton is produced in organic agricultural systems that produce food and fiber according to clearly established standards. Organic agriculture prohibits the use of toxic and persistent chemical pesticides and fertilizers, as well as genetically modified organisms. It seeks to build biologically diverse agricultural systems, replenish and maintain soil fertility, and promote a healthy environment.
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