The Effects of GM Technology on Maize Yield

In the United States, maize (Zea mays L.) farmers have adopted genetic-modification technology rapidly since its first commercialization in 1996. By 2012, 88% of U.S. maize is planted with genetically modified (GM) hybrids. Our objective in the paper is to present an empirical analysis of the determinants of U.S. maize yield using experimental maize production data, with a focus on the interaction effects of GM technology, management, and risk. Genetic-modification technology had a stronger impact on the lower end of maize yield distribution within a trial thereby reducing exposure to downside risk. A strong interaction exists between GM technology and crop rotations: GM reduces the adverse effects of maize-maize rotation on yield. As such, GM technology is found to be a substitute for crop rotation. Genetic-modification technology increases the yield gains associated with higher planting density. This indicates that GM technology offers good prospects for future improvements in maize productivity.