A Position Statement
Dennis Keeney, Director

May, 1997

To date, there have been two major categories of commercial applications of biotechnology to crop production. One has been the development of crops expressing the Bacillus thuringiensis (Bt) gene for control of certain lepidopteran insects. The most important target insect in the Midwest is the European corn borer. The other application has been the development and marketing of corn and soybeans resistant to herbicides. Those already on the market include soybeans resistant to glyphosate and sulfonylurea herbicides, and corn resistant to imazethapyr.

It appears likely that agribusiness will be placing heavy emphasis on the development and marketing of dozens of additional herbicide-resistant crops. Herbicide-tolerant crops pose complex challenges for researchers, farmers and the Leopold Center. Entomologists, farmers, and many leaders in the crop protection industry are concerned about the development of resistance to Bt in the case of the corn borer, several cotton pests, and the Colorado potato beetle. Overuse of herbicides can also lead to weeds resistant to these herbicides. Weed scientists believe that weed resistance will develop with the prolonged use of herbicide-resistant crops. While herbicide-resistant crops provide short-term flexibility in the design of weed management systems, the resulting resistant weeds and a narrowed list of management options may become long-term problems that force farmers to purchase even more expensive external inputs.

The Leopold Center has always taken the position that new technologies that will help family farms thrive in the long term while enhancing the resource base and protecting the environment are the technologies that the Center should help develop and transfer through sound on-farm research and extension education activities. Within this educational framework, the Leopold Center regards weed management as one of the most important issues in Iowa agriculture. We are supporting a Weed Management Issue Team (Bob Hartzler, Agronomy, Team Leader). We also have supported projects that have developed ways to reduce herbicide use through combinations of lower herbicide rates, banding, tillage, cover and smother crops, and rotations. These projects in no way represent a statement against herbicides; rather they are designed to offer options for appropriate and more economical herbicide use in Iowa row crop agriculture.

Because of the substantial private sector investment in research on herbicide- tolerant crops, the Leopold Center has decided to direct its limited resources toward development of farming systems that are not reliant on crop varieties genetically transformed to tolerate herbicide applications. We will not sponsor research designed to develop or expand the adoption of systems incorporating herbicide-tolerant crop varieties, but will support research that includes evaluation of these technologies and their consequences as part of diverse cropping systems. The Leopold Center has previously sponsored research on the consequences of adoption of Bt corn.

Principal investigators should keep this policy in mind as they plan experiments and prepare Leopold Center project proposals. This policy, and the factors leading to the Leopold Center's decision, are not easy to explain in a short statement. Therefore, feel free to contact me for questions and clarification. We welcome continued open discussion on this and other issues arising from agricultural applications of biotechnology.

8/19/97