Genetically Modified Crops and the New Paradigm for Herbicide Use in Row Crops

Genetically modified glyphosate-resistant (GR) crops quickly revolutionized weed management in row crops in North and South America after their introduction in the mid-1990s. Growers made GR crops the most rapidly adopted technology in the history of agriculture. In the United States, GR soybeans enabled a new use for glyphosate that was effective, easy, economical, and environmentally safe. This use of glyphosate reduced the value of selective herbicides, and in seven years, the number of herbicide actives used on at least 10 % of the soybean acreage in the United States declined from 11 to just 1, glyphosate. Many growers used only glyphosate for weed management, and now GR weeds are widespread and forcing growers to diversify their weed management practices. Weed management experts agree that no single management technology is sustainable when used alone; weeds will eventually adapt. Growers must use more diverse and integrated pest management practices incorporating combinations of the best chemical, crop, and cultural systems. This new paradigm for herbicide use is creating opportunities for new application and formulation technologies.