Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: May 1, 2003
Publication Date: June 1, 2003
Citation: Larkin, R.P., Griffin, T.S. 2003. Control of soilborne pathogens of potato with brassica crop rotations. Phytopathology. 93: S48 Technical Abstract: Brassica spp. and related plants produce glucosinolates, which break down in soil to produce volatile compounds that are toxic to many soil organisms, and have been associated with reductions in soilborne pathogens. Selected Brassica crops, including canola, rape, oilseed radish, turnip, yellow mustard, and white mustard, were evaluated for control of various potato pathogens in culture, in greenhouse tests, and in field trials on commercial potato farms. All Brassica crops reduced inoculum levels of Rhizoctonia solani (20-65% reduction) relative to a potato crop, and radish, rape, and white mustard reduced subsequent potato seedling disease by 30-85% in greenhouse tests. In on-farm trials at sites with substantial disease problems, white mustard, rape, and canola grown as a green manure rotation crop reduced powdery scab by 15-40% and black scurf by 50-85%, and white mustard reduced common scab by 25% in the subsequent potato crop relative to a standard oats or ryegrass rotation crop. These results indicate that Brassica crops have potential for use in the control of powdery scab, Rhizoctonia disease, and other soilborne disease problems.