Transgenic plants are plants that have been genetically engineered, a breeding approach that uses recombinant DNA techniques to create plants with new characteristics. Transgenic plants are produced by adding one or more genes to a plant's genome, by a process called transformation. They are identified as a class of genetically modified organism (GMO).
Transgenic plants have been developed for a variety of reasons: longer shelf life, disease resistance, herbicide resistance, and pest resistance. The first transgenic crop approved for sale in the US, in 1994, was the FlavrSavr tomato, which was intended to have a longer shelf life.
Today, there are more than 10,677,000 km² of transgenic plants being grown throughout the world1. There are three general types of transgenic plants: those with genes to improve the quality of the product, those with genes to allow them to resist disease or herbivory (consumption by herbivores, usually insects), and plants with genes that allow them to be resistant to the effects of specific herbicides. A developing group of transgenic plants is that of nutraceuticals, or plants designed to possess properties that make them healthier in specific ways. Examples include plants that produce vaccines or higher concentrations of specific compounds like lycopene.
Transgenic crops are grown world wide, although the greatest concentration of transgenic crops is in the United States, at 63% of the world total in 2003. At that time, 81% of the soybeans, 73% of the cotton and 40% of the corn being grown were transgenic. At that time most of the transgenic crops had genes either for herbicide resistance or for insect resistance1.
An emerging class of transgenic plant, sometimes known as pharmacrops, aims to use plants to manufacture other products, such as pharmaceuticals and industrial chemicals. Testing of a variety of these crops has been underway for several years. It appears that no such products have yet been used in the commercial market.
source : hydroponicsearch
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