These crops were developed to help farmers control weeds. Because the new crops are resistant to Roundup, the herbicide can be used in the fields to eliminate unwanted foliage. Current Roundup Ready crops include soy, corn, canola, alfalfa, cotton, and sorghum, with wheat under development. Roundup Ready crop seeds have notoriously been referred to as "terminator seeds. Each year, farmers must purchase the most recent strain of seed from Monsanto. Genetically Engineered GE seeds were commercially introduced in the United States for major field crops in , with adoption rates increasing rapidly in the years that followed.
Currently, over 90 percent of U. GE crops are broadly classified in this data product as herbicide-tolerant HT , insect-resistant Bt , or stacked varieties that are a combination of both HT and Bt traits. Although other GE traits have been developed such as virus and fungus resistance, drought resistance, and enhanced protein, oil, or vitamin content , HT and Bt traits are the most commonly used in U. While HT seeds are also widely used in alfalfa, canola, and sugar beet production, most GE acres are planted to three major field crops: corn, cotton, and soybeans.
Herbicide-tolerant HT crops , which tolerate specific broad-spectrum herbicides such as glyphosate, glufosinate, and dicamba , provide farmers with a broad variety of options for effective weed control. Based on USDA survey data, the percent of domestic soybean acres planted with HT seeds rose from 17 percent in to 68 percent in , before plateauing at 94 percent in To add a trait to a crop plant, the gene must be inserted along with some additional genetic material.
This additional genetic material includes a promoter sequence that, in part, determines how the new trait is expressed in the plant. For example, the promoter may cause to protein to be expressed in certain parts of the plants or only during a particular period of time. There is a marker gene that allows plant breeders to easily determine which plants have been transformed. Herbicide and antibiotic tolerance promoters are commonly used to identify transformed plants.
There may also be a plasmid or vector sequence that allows for rapid multiplication of the gene of interest in a bacterial host prior to insertion in the crop plant. Federal food law requires premarket approval for food additives, whether or not they are the products of biotechnology. FDA treats substances added to food products through recombinant DNA techniques as food additives if they are significantly different in structure, function or amount than substances currently found in food.
However, if a new food product developed through biotechnology does not contain substances that are significantly different from those already in the diet, it does not require premarket approval. Products that are genetically engineered to provide pesticide traits, such as resistance to the corn borer, are also subject to regulation by the Environmental Protection Agency. Currently, genetically modified foods in the United States do not require special labeling to notify consumers.
By the mids, our researchers had identified both plant and microbial genes that conferred increased herbicide tolerance in laboratory tests and in the USDA approved the first field test of Roundup Ready plants. This was a Roundup resistant crop of genetically modified tomato plants that were tolerant to Roundup.
A few years later, the bacterial gene that would become the Roundup Ready trait was discovered, isolated and introduced into crops. Roundup Ready Soybeans are genetically engineered soybeans that have had their DNA altered so that they can withstand the herbicide glyphosate which is the active ingredient in the herbicide, Roundup. These soybeans are tolerant to glyphosate because each soybean seed has had the Roundup Ready gene injected into it before it is planted. This means that farmers can spray their fields with the herbicide to remove weeds without killing their crop.
As you can see, the introduction of Roundup Ready crops in changed farming and agricultural science!
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