Determining the Value of Bt-Corn in the Northeast
Bryan Dillehay
Graduate Student in Agronomy
Department of Crop and Soil Sciences
Penn State
February 2002
I have recently begun a graduate program at Penn State to help work on a collaborative project that includes Penn State, the University of Maryland, and Cornell University to begin to access the economic value of many insect-resistant corn hybrids, otherwise known as Bt-corn.
Corn growers in the Northeast lose over $100 million each year to European corn borer infestations. In the past, it has been expensive and difficult to control for European corn borer with conventional insecticides ($15-$20 per acre), and often times without any economic return. In contrast, recent Bt technology has provided a relatively low cost alternative ($7-$10 per acre) with extraordinary pest control. Field trials have shown that Bt-corn provides good yield protection at moderate and high infestations of European corn borer. However, at minimal infestations, the economic benefit of Bt-corn is unclear.
Principal investigators on the project that I am working with include Dennis Calvin, Jeff Hyde, Gretchen Kuldau, Greg Roth, and Del Voight (Penn State) and Robert Kratochvil (University of Maryland) and John Losey (Cornell). We will investigate the economic value of Bt-corn and how it could fit into an IPM program for the Northeast corn producer. We will compare Bt hybrids, their near isolines (same genetics but without Bt), and popular traditional hybrids from 5 prominent seed companies sold within the Northeast. In addition, the investigators will be evaluating the different hybrids on numerous characteristics ranging from yield and test weight to toxins and disease.
So far, two years of information has been collected, with the third and final year of the experiment being planted this spring. The field trials have been grown at 2 locations in Maryland, and 4 locations in Pennsylvania. Preliminary interpretations are indicating a yield advantage to using Bt-corn of about 8 bushels per acre, however this value varied among locations and years. For example, during the year 2001, a trial that was grown in Hershey, PA had a high infestation of European corn borer and consequently the Bt-hybrids yielded a 12 bushel per acre advantage over their isolines. Alternatively at the same location in 2000, a slightly lower infestation occurred, and the Bt-hybrids did not provide any advantage. Concurrently, an interesting trend that is appearing in this study is that Bt-corn takes longer to dry down as compared to conventional hybrids. At harvest, Bt-hybrids are exhibiting between 0.1% and 3% differences in moisture content, depending on the location. Averaged over all sites, the Bt-hybrids have been about 0.9 % wetter. Harvesting at a high moisture can lead to increased drying costs or may call for harvest dates to be delayed slightly. In addition, we have found no differences among the test weights of Bt-hybrids and their isolines. Ears and grain from the plots is currently being evaluated for ear molds and mycotoxin levels.
Farmers have identified research on the use of genetically altered crops for pest management as a top priority in previous IPM surveys. The results of this multi-year study will be provided to extension agents and industry personnel as well. We are also planning to develop an extension publication and conduct several field days next year that will explain the project results in more detail.