Document: DIA-3-13-2

Soil biodiversity and agricultural productivity.

WALL, D.H.*

Colorado State University, Fort Collins, CO 80523 USA ¹

Abstract:
Soil pathogens cause plant disease resulting in decreased crop yield and/or quality, and economic loss. Until recently, soil pathogens were controlled primarily by chemicals, a method that affected soils, soil biodiversity and ecosystem processes on local and global scales. International policies (e.g., the Kyoto and Montreal Protocols and the Convention on Biodiversity), driven by public and grower concerns about food safety and our future global environment, are rapidly changing the management tools for soil pathogens. For example, the Montreal Protocol bans use of highly effective nematicides and fungicides (mostly hydrocarbon-based) because of contamination of water, degradation of the atmosphere, and risk to farmworkers and consumers. These policies require us to control soil pathogens based on ecological knowledge of soil biodiversity and the ecosystem processes they influence, to minimize pathogens and promote sustainable ecosystems. For example, decomposition in most natural systems involves multiple soil species and functional groups, whereas in intensively managed agroecosystems, soil biodiversity generally decreases, and decomposition occurs by bacterial pathways. I will illustrate how agroecosystems may be manipulated to lessen soil pathogens (nematodes), plant disease and improve crop productivity. Syntheses, integrated research and new technologies are all required if we are to sustainably manage agricultural soil and its biodiversity as a natural resource.

Keywords:

This abstract is being presented at: 9:30 AM in session:
Symposium # 14: Ecology and Agriculture.