Soil Ecology Research Laboratory

Assessing the Impact of Biotechnology on biodiversity: Effect of Transgenic Maize on Non-Target Soil Organisms

Project summary:

Transgenic Bt maize has tremendous potential for the management of pest complexes currently responsible for widespread insecticide use and yield losses. The likelihood of this biotechnology being adopted worldwide makes it imperative that we fully understand both positive and negative effects on non-target organisms arising from its use in the wide range of ecosystems where maize is grown. Changes in the density, diversity, or activity of soil organisms adversely affect soil structure, the availability of plant nutrients, and the natural control of pests. Risk assessment by EPA and USDA for registration of Bt maize in the U. S. evaluated non-target soil organisms in the temperate region. However, tropical ecosystems contain different organisms and have far greater diversity than temperate ecosystems. Similar tests are now needed in tropical regions to assess direct and indirect risks of Bt maize to non-target organisms, particularly soil arthropods, bacteria, fungi, protozoa, and nematodes. Currently at Cornell, a comparative assessment of both transgenic Bt maize and soil insecticide on non-target soil organisms is underway. We propose to collaborate with scientists in developing countries (starting with those at CIAT in Colombia) to develop and implement a practical program based on our current research to quantify the impact of transgenic Bt maize and soil insecticides on non-target and beneficial soil arthropods, nematodes, and microbes. This effort will include scientists from environmental conservation groups (ABI, Association for Biological Information, and CDC, Centro de Datos para la Conservac16n) who will collaborate in developing a biodiversity database and in a biodiversity assessment of the maize ecosystem. Through our collaborations, we will develop and implement a program to examine both the direct (toxicity) and indirect (trophic interaction) effects on the soil biota by examining the biodiversity of the food web in all of its complexity. Understanding the comparative risks of transgenic Bt maize and soil insecticide is important for the optimal management of physical, chemical and biological aspects of the soil, which in turn, will optimize returns and the long-term sustainability of the agro-ecosystem. Through this work, we will be able to provide regulatory agencies with additional information needed to evaluate the relative risks associated with transgenic Bt maize in comparison to the use of soil insecticides.

Objectives:

Aim: To quantify the impacts of transgenic maize and soil insecticides on non-target and beneficial soil arthropods, nematodes, and microbes in developing countries.
1. Continue research development of risk assessment methods for non-target soil organisms in transgenic Bt maize field plots at Cornell.
2. Collaborate with CIAT and ABI/CDC agricultural and environmental conservation scientists to modify the risk assessment methods for non-target soil organisms under development at Cornell for practical implementation at CIAT, and develop a biodiversity database for the maize ecosystem at CIAT, Colombia.
3. Generate data on potential risks associated with transgenic maize for non-target organisms by implementing field trials at CIAT, Colombia.
4. Share successful risk assesment protocols with other international centers in developing countries, such as Mexico (CIMMYT), Costa Rica (CATIE), Honduras (Zamorano), Africa (TSBF, KARI), and S.E. Asia (IRRI).
5. Use results to quantify specific risks and provide a scientific basis to assess risks of transgenic crops and soil insecticides to soil organisms in developing tropical countries.

Project staff:

Lead Principal Investigator: John Losey, Dept. of Entomology, Cornell University
Principal Investigators: Antonio DiTommaso, John Duxbury, Joseph Esnard, Janice Thies (Cornell University), Daniel Peck (CIAT)
Co-Investigators: Leslie Allee, Medha Devare