The Challenges and Potential for Future Agronomic Traits in Soybeans

Soybeans are grown in many parts of the world and are a primary source of vegetable oil and protein for use in food, feed, and industrial applications (Endres, 1992, 2001). A variety of pests have devastating effects on the agronomics and economics of soybean production, affecting yield and quality of grain and seed; this list of pests includes weeds, insects, fungi, nematodes, and viruses. One of the best examples of a modern world agricultural technology altering the path of a world commodity crop is in the development of soybeans that are tolerant to the herbicide glyphosate. Unlike previous traits in soybean, the rapid commercial adoption of glyphosatetolerant soybeans provided tangible benefits to the grower, and enhanced productivity that fueled the trait adoption (James, 2001; Carpenter et al., 2002). Since their introduction in 1996, glyphosate-tolerant soybeans have grown to occupy over 33.3 million hectares—more than 46% of the global soybean acreage. In addition, soybean acreage in Argentina rose from 7 to 11 million hectares, a result likely facilitated by the adoption of Roundup Ready soybeans. The rapid rate of adoption (shown in Figure 1) would likely have been mirrored in other soybean-producing countries if the regulatory, intellectual property, and equity criteria for deployment of agricultural technology had been achieved. The commercial acceptance of glyphosate-tolerant soybeans has set a high hurdle and a new expectation for biotechnology and future soybean agronomic traits. New traits targeted for soybean production that possess the potential for more sustainable and consistent production continue to be evaluated. The major global soybean production areas for the 2001/02 production season are listed in Table 1 (Soyatech, 2003). Most of the soybean growing countries in Table 1 and a significant amount of global areas would be beneficiaries of new traits currently being evaluated by soybean research programs. Traits that increase production efficiencies and lower the cost and use of insecticide applications have the highest success due to a direct benefit to the producer. Agronomic challenges represent opportunities for production enhancement; using biotechnology, several opportunities to promote more sustainable and environmentally friendly agriculture are likely achievable. As soybeans have expanded in the world, soybean pests and diseases have become more severe. Tropical and subtropical climates present environmental and biotic stress environments that favor pest infestations and represent the largest region of opportunity. Work to develop soybeans that are resistant to key insect pests are one example of technology with demonstrated proof of concept (Walker, All, McPherson, Boerma, & Parrot, 2000), and where few if any technical obstacles impair commercialization. Another area of focus has been in the research and evaluation of soybeans that are resistant to viruses (United States Department of Agriculture Animal and Plant Health Inspection Service [USDA APHIS], 2003). Timothy Conner, E. Hamer Paschal, Alberto Barbero, and Eric Johnson Monsanto Company Soybeans are the primary source of the world’s supply of protein and vegetable oil. The demand for increased production of soybeans is forecasted to mirror the world’s population growth and demand for protein and edible oil. In order to meet this demand, production acreages are increasing in key global soybean areas; moreover, technologies to increase production efficiency through transgenic trait control of yield-robbing pests and pathogens, while lowering the cost and use of insecticide and other less efficient agricultural practices, are very much a reality. In addition, the increase in more efficient and more sustainable agronomic practices will help fuel some key improvements in soybean quality and new opportunities for agricultural solutions resulting in feed improvements, health benefits through foods, and new industrial opportunities contributing to a more sustainable global environment.