Monday, November 5, 2007 - 11:00 AM
53-6
Disease risk and management in intensive corn production systems.
Gary Munkvold, Iowa State University, 160 Seed Science Center, Ames, IA 50011
The increasing land area devoted to corn production will lead to more frequent use of consecutive corn planting within fields and across the landscape. Because many corn pathogens survive and proliferate in corn plant residue, this crop production pattern is likely to elevate pathogen inoculum levels and increase the risk of disease. This will impact corn yields; the magnitude of this impact will tend to increase over time but will be subject to annual fluctuations related to weather. Corn disease management under these conditions will require an emphasis on tactics other than crop rotation, and corn price dynamics will exert a strong influence on the tactics implemented. Corn hybrids adapted to perform in a near-continuous corn system must be equipped with enhanced resistance to a range of residue-borne diseases and tolerance to early-season temperature stress. An eventual shift to cellulose-based ethanol production could radically change this outlook through the removal of corn plant residue or the incorporation of other crops into the rotation.