Comment submitted by Dr Scott Stewart, University of Tennessee

TO: Environmental Protection Agency RE: Approval of MON 89034 (second-generation Bt corn) During my career, I have performed multiple experiments with various Bt corn and Bt cotton traits as part of my research and extension activities in the South. This year, I've had the opportunity to work with MON 89034 has part of my testing program at the University of Tennessee. As you know, MON 89034 is a second- generation biotech product that produces two Bt toxins (Cry1AC, present in the existing YieldGard corns, and Cry2AB2). Commercially available Bt corn traits are highly effective in controlling infestations of European corn borer and also the southwestern corn borer (the species most problematic in the Midsouth). Thus, the addition of a second Bt gene (Cry2AB2) is currently not needed to improved the field performance of Bt corn technologies that are already on the market. However, because the two cry proteins present in MON 89034 represent different ?classes? of Bt toxins, it is scientifically logical to expect the addition of this second gene will delay or prevent the development of resistance to Bt toxins in corn borer populations. The data clearly indicates that MON 89034 offers greatly improved control of corn earworm and fall armyworm compared with the original YieldGard (Cry1AC) technology. Because the existing Cry1AC technology has relatively little activity on corn earworm and fall armyworm, it is not clear to me how this new technology will impact resistance management for these species. However, the improved field performance will be attractive to growers in the South where corn earworm and fall armyworm are more important. I encourage the EPA to strongly consider giving full registration to MON 89034. I believe this product will greatly reduce the risk of resistance to Bt corn developing in populations of European and southwestern corn borer. I also expect that this technology will reduce economic damage caused by corn earworm and fall armyworm, and this should reduce the use foliar applied insecticides currently used for the control of these pests. Regards, Dr. Scott Stewart Associate Professor The University of Tennessee West TN Research and Education Center 605 Airways Blvd. Jackson, TN 38301 Phone: 731.425.4709 E-mail: sdstewart@utk.edu