Wednesday, May 19, 2010

On the other hand, the engineered crops currently being grown are safe and cause less environmental damage than their conventional cousins. Some GE crops allow farmers to use fewer chemical pesticides. Others support notili farming, which protects topsoil and reduces agricultural runoff into rivers and streams.

-Use fewer chemicals

-Protect topsoil and reduce runoff

Meanwhile, in developing nations with millions of poor subsistence farmers, GE crops are proving highly popular. Farmers in India and China who are growing cotton engineered to produce the Bt pesticide benefit because they can use fewer chemical pesticides and enjoy sharply increased yields. That translates into fewer pesticide poisonings and higher income. In India, cotton production doubled between 2002 and 2007. (Critics charge that failed harvests of Bt cotton in India have led to farmer suicides, but independent researchers have found no link.)

-Higher production and income

Consumer benefits probably will come sooner overseas than in the United States. India soon could market two dietary mainstays from genetically engineered crops; water-conserving mustard and insect-resistant eggplant. And China is becoming a powerhouse with its own biotech crops, which won't bear the Monsanto or DuPont logo.

The Gates Foundation is funding projects to boost nutrients in sorghum and cassava, two staple African crops. And, with the Rockefeller Foundation's help, Golden Rice may soon move from the lab to fields in Southeast Asia. That long-awaited variety produces betacarotene, which can prevent vitamin A deficiency and blindness.

-Boost nutrients in crops in poorer countries

Jacobson, M.. (2009, July). Biotech: Scourge or Savior? Nutrition Action Health Letter, 36(6), 2. Retrieved May 19, 2010, from Platinum Periodicals. (Document ID: 1817204491).

On the Farm

Plant genetic engineering has progressed faster than that of mammals, because efficient delivery systems have been developed for inserting genes in plants, and it is relatively easy to regenerate an entire plant from a single genetically altered cell. In 1998, the United States had about 55 million acres of genetically engineered corn, soybean, and cotton, as estimated by the U.S. Department of Agriculture. The goal of crop genetic engineering is to reduce farm production costs and pesticide use and to increase yield and nutritional content.

-Reduce production costs, pesticide use, increase yield and nutrition

The first genetically engineered and commercialized insect-resistant crop was the NewLeaf Russet Burbank potato, which is highly resistant to the Colorado potato beetle. It was created using the gene for Bt toxin, a natural insecticidal protein made by the bacterium Bacillus thuringiensis. Bt genes from different strains of the microbe have been engineered into corn, cotton, tomato, potato, tobacco, rice, apple, eggplant, cabbage, canola, alfalfa, walnut, poplar, spruce, and cranberry. Insect attack is markedly reduced, circumventing the need to spray with expensive and hazardous insecticides. The toxin destroys the digestive system of certain insects, such as caterpillars and rootworms, but it does not persist in the environment and is safe for people, other mammals, and fish. Future research is focused on creating more potent versions of Bt, to expand the types of insects controlled and to reduce the development of insect resistance to Bt.

-Example of insect-resistant crops (Bt)

To protect crops from serious viral damage, a method known as "cross-protection" has been applied. It involves inserting a viral gene into the plant's cells, so that the plant begins to express a piece (usually the outer coat protein) of the virus. Such transgenic plants resist infection entirely or display greatly reduced symptoms, as if they were naturally vaccinated against the virus. Scientists do not understand how cross-protection works, but they have used it to make numerous crops resistant to various viruses. The impact of this technology cannot be underestimated. For example, creation of a genetically engineered papaya that resists ringspot virus infection saved a nearly devastated industry in Hawaii.

-Using genetic engineering to vaccinate crops against viruses

Many crops are now being engineered to survive spraying with biodegradable herbicides. These herbicide-resistant plants were created by altering their protein targets that bind the herbicide and by adding genes for enzymes that destroy the herbicide. This approach encourages the use of biodegradable herbicides, such as glyphosate.

-Herbicide resistant

Genetic engineers are learning to design canola, soybean, and palm to produce everything from improved oils to plastics. Oils rich in oleic acid are preferred for cooking, while stearic acid is a raw material for soaps and detergents, and ricinoleic acid is valuable for industrial lubricants. A number of researchers have engineered plants with genes to make natural, biodegradable plastics that can lower our dependence on petroleum products and reduce garbage levels in landfills.

-Plants can now produce improved oils and biodegradable, natural plastics

Some scientists are developing caffeine-free coffee beans by genetically inhibiting the gene that controls caffeine synthesis. Others are working to raise the levels of nutrients, such as vitamin E, carotenoids, flavonoids, and glucosinolates, which are naturally present in avocado, carrots, tea, and broccoli, respectively. And the protein content of corn is being enhanced. Clinical research suggests that elevated intake of vitamins and phytochemicals reduces the risk of developing cancers and cardiovascular disease and slows some aging processes. The low micronutrient levels in staple crops such as wheat, rice, potatoes, and cassava lead to deficient diets for 800 million people worldwide. Thus, using genetic engineering to increase the nutritional value of food is an especially exciting development with enormous potential benefits.

-Caffeine-free, increasing nutrients, vitamins

In the future, plant genetic engineers will be tackling almost every trait imaginable. Efforts are under way to create crops that are more tolerant of drought, saltwater, heat, ultraviolet radiation, and injury by freezing. Even aging, sweetness, flower color, and fragrance are being altered by plant geneticists. These scientists will soon be focusing more on putting multiple genes for many traits—such as resistance to insects, fungi, viruses, bacteria, and herbicides— into one plant variety.

-Greater tolerance of environmental stress

Christopher, David A. "Genetic Engineering Will Benefit Society." Opposing Viewpoints: Genetic Engineering. Ed. James D. Torr. San Diego: Greenhaven Press, 2001. Opposing Viewpoints Resource Center. Gale. West Seneca West Senior High School Lib. 19 May. 2010

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