Roger Elmore, Iowa State Univ, 2104 Agronomy Hall, Ames, IA 50011
Transgenic crops revolutionized Midwest farming systems in a decade. Thirty-nine percent of Midwest corn is transgenic while 88% of the nation’s transgenic corn is grown in the Midwest. This will increase especially as more producers use rootworm resistant corn hybrids. Eighty-nine percent of the soybeans grown in the Midwest are transgenic while 83% of the nation’s transgenic soybeans are grown in the region. All transgenic soybeans are herbicide resistant, while transgenic corn hybrids have insect resistance and/or herbicide resistance traits. The dramatic increase in use of transgenic crops has resulted in major shifts in herbicide and insecticide usage, as well as altering tillage systems and crop rotations used. Transgenic traits certainly add versatility to insect and weed management systems in both corn and soybean. The success of relay intercropping and skip-row cropping systems hinge on the use of transgenic cultivars. However, weed control problems increase with time, reduced herbicide and insecticide costs offset rapidly increasing seed costs, and transgenic cultivars allow progressively larger farming operations. Traditional breeding programs suffer as attention is directed towards incorporation of resistance and stress tolerance, and not necessarily yield potential. Are we ignoring integrated pest management and long-term impacts of transgenic management systems? Transgenic crops have revolutionized Midwest agriculture. An old saying declares, "Revolutions never go backwards." Within any revolution it pays to stop and look around at the direction of the cause.