Profiling Microbial Communities in Soils from Organic, Sustainable, and Conventional Cropping Systems

View the project final report

• 2012 annual report

Commodities

• Agronomic: general grain crops

Practices

• Crop Production: crop rotation, organic fertilizers
• Education and Training: on-farm/ranch research
• Production Systems: organic agriculture
• Soil Management: soil analysis, soil microbiology

We will investigate the functional differences between microbial communities found in soils with a history of diverse crop rotations or native plant populations and biologically-based fertility management; and conventionally-managed soils. We will use direct sequencing of DNA extracted from soils of five long-term research and working farm sites where organic and conventional practices are used side by side on the same base soils, to provide a detailed inventory of bacterial strains present under each management regime. The objectives of this project are 1) to construct a set of phylogenetic profiles of soil communities under a broad range of management practices, which will allow us to see which bacterial populations are favored by which practices, and 2) to use these profiles to make predictions about the metabolic capabilities of these communities, which can be used to guide further research into the impacts of organic and conventional practices on soil biological functions. The outcome of our research will be a contribution to the building of a detailed knowledge base about the impact of farming systems on essential soil biological functions such as nutrient cycling and disease suppression. This will allow researchers to work with farmers to develop recommendations for rotation, nutrient management, and other practices to maximize fertility- and health-enhancing soil functions and foresee and avoid unwanted side effects of inputs or practices.

The short-term outcomes of this project will be: 1) construction of a set of phylogenetic profiles of soil communities under a broad range of management practices and 2) use of these profiles to make predictions about the metabolic capabilities of these communities, which can be used to guide further research into the impacts of organic and conventional practices on soil biological functions. Intermediate-term outcomes include: 1) increased understanding of the effects of organic management on soil biotic communities and 2) empowerment of growers to foresee the impacts of particular inputs and practices on soil functions relevant to crop success.