Submitted to: American Phytopathological Society
Publication Type: Abstract only
Publication Acceptance Date: 5/20/2011
Publication Date: 6/13/2011
Citation: Larkin, R.P., Olanya, O.M., Halloran, J.M., He, Z., Honeycutt, C. 2011. Use of disease-suppressive Brassica rotation crops in potato production: overview of 10 years of field trials. American Phytopathological Society. 101:S98. Interpretive Summary:
Technical Abstract: Disease-suppressive Brassica rotation crops have shown promise for management of soilborne diseases and enhanced yield in a variety of crop production systems. Over the last 10 years, numerous field trials have focused on how to best use Brassica crops in potato rotations in the Northeast, including which crops to use, what diseases are affected, and how to implement and manage these crops (as cover, harvested, or green manure crops). A summary of over 70 individual trials indicated that, although results varied by field and year, positive effects have been observed in most trials. Yield was significantly improved in 52% of the trials, with increases up to 38%. Black scurf was significantly reduced in 70% of the trials, with reductions up to 95% and an average reduction of 30% relative to typical rotation crops. Common scab was reduced in 40% of the trials, with reductions up to 50%. Powdery scab and Verticillium wilt were also reduced in most of the trials where they occurred. Overall, mustard green manures worked best for reducing most soilborne diseases, but rapeseed green manure was best for black scurf. In general, green manures provided the best results, but crops harvested for seed also significantly reduced disease. However, due to the short growing season, Brassica crops were not effective as a fall cover crop. This research demonstrated that Brassica rotation crops can substantially reduce soilborne disease problems, but cannot completely control them.