Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Impacts of crop rotation and irrigation on soilborne diseases and soil microbial communities

Authors
item Larkin, Robert
item Honeycutt, Charles
item Olanya, Modesto
item Halloran, John
item He, Zhongqi

Submitted to: Sustainable potato production: global case studies
Publication Type: Book / Chapter
Publication Acceptance Date: November 30, 2011
Publication Date: May 31, 2012
Citation: Larkin, R.P., Honeycutt, C.W., Olanya, O.M., Halloran, J.M., He, Z. 2012. Impacts of crop rotation and irrigation on soilborne diseases and soil microbial communities. In: He, Z., Larkin, R.P., Honeycutt, C.W., editors. Sustainable potato production: global case studies. Amsterdam, The Netherlands: Springer. p. 23-41.

Technical Abstract: Crop rotation provides numerous benefits to crop production, and is essential to reduce the build-up of soilborne plant pathogens and diseases that can devastate potato crops grown in multiple consecutive years. Crop rotations can reduce soilborne diseases through a variety of mechanisms, including changes in soil microbial communities, but different types of rotation crops can have very different effects. In recent research in Maine, full-season rotation crops, such as barley, ryegrass, canola, and rapeseed, substantially reduced (15-50% reduction) Rhizoctonia and other soilborne potato diseases. Addition of a fall cover crop of winter rye to existing rotations further reduced Rhizoctonia and common scab diseases by another 5-20%. Use of specific disease-suppressive rotation crops as green manures can provide even greater reductions in soilborne diseases. In an ongoing large-scale study examining the effects of several different cropping system strategies both with and without irrigation, a disease-suppressive approach (utilizing Brassica and sudangrass green manures, fall cover crops, and high crop diversity) reduced soilborne diseases better than any other cropping system (25 to 58% reduction), and both the disease-suppressive and a soil improving (with compost amendments) system substantially increased tuber yield (19 to 42%). Irrigation also increased yield (~28%) in most systems. Combining the disease-suppressive rotation with irrigation increased yield by 53% relative to non-irrigated continuous potato. Combining effective crop rotations with other compatible components of integrated pest management can provide more effective and sustainable disease management and crop productivity.

Last Modified: 7/25/2014