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Genetic Engineering
Plant traits are encoded in the DNA of their genes. In
1973 it became possible to identify and splice, or
recombine, specific DNA molecules, leading to
recombinant DNA technology, or genetic engineering,
which allows scientists to copy and exchange genes among
organisms to introduce new characteristics, such as
resistance to herbicides or insects. Plants developed
using genetic engineering are often called transgenic
plants.
Although genetic engineering of foods was commercialized
first in yeast to produce rennet for making cheese in
the late 1980s in Europe, the first commercial
genetically engineered crop was the FLAVR SAVR tomato
from Calgene Inc., first sold in 1994. The first
large-scale introduction of a transgenic crop occurred
in 1995 with the release of herbicide-tolerant soybeans.
Along with insect resistance conferred by the
Bacillus thuringiensis (Bt) protein, this first
generation of genetically engineered crops exhibited
improved agronomic traits.
that 68 percent of soybeans, 26 percent of corn and 69
percent of cotton in the United States were planted with
varieties enhanced by genetic engineering.
Worldwide,
130 million acres of transgenic crops were grown in
2001. Genetically engineered crops have continued to
increase 10-15% annually, with over 300 million acres
(120 M ha) grown in 25 countries in 2008 (ISAAA 2009).
The second generation of transgenic crops to enter the
market is expected to incorporate many value-enhanced
qualities, such as higher nutrient contents, increased
fertilizer use efficiency and resistance to
environmental stresses such drought.
One example of
quality enhancement is Golden Rice®, a rice
variety that accumulates beta-carotene (the precursor to
vitamin A) and iron in the grain, potentially reducing
childhood blindness and anemia in countries where rice
is a staple food.
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