The overall United States percent of corn, soybean, and cotton with genetically modified seeds which has nearly doubled in the last five years. The term "GMO" has historically been defined as organisms whose genetic makeup has been altered by conventional cross breeding or by "mutagenesis" breeding.
U.S. Department of Agriculture: Genetically Modified Crops - http://www.ers.usda.gov/Publications/EIB11/
Ten years after the first generation of genetically engineered (GE) varieties became commercially available, adoption of these varieties by U.S. farmers is widespread for major crops.
USDA-Research and Science - http://www.usda.gov/wps/portal/!ut/p/_s.7_0_A/7_0_1OB?navtype=SU&navid=RESEARCH_SCIENCE
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