|Larkin, Robert - Bob|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 9/1/2014
Publication Date: 10/1/2014
Citation: Larkin, R.P., Halloran, J.M. 2014. Cumulative and residual effects of potato cropping system management strategies on soilborne diseases and soil microbial communities over time. Phytopathology104 (Suppl 3):S3.66.
Technical Abstract: In field trials established in 2004, different 3-yr potato cropping systems focused on specific management goals of soil conservation (SC), soil improvement (SI), and disease-suppression (DS) were evaluated and compared to a 2-yr standard rotation (SQ) and a non-rotation control (PP) for their effects on soilborne diseases, tuber yield, and soil microbial community characteristics under both rainfed and irrigated conditions. Systems were actively managed through 2010, with potato crops planted in subsequent years (2011-12) to examine residual effects. All rotations reduced disease and increased yield over baseline levels after one rotation cycle, but diseases increased overall after two rotation cycles, then stabilized. The DS system, which utilized Brassica and other disease-suppressive rotation crops, maintained lower soilborne disease levels than all other rotations, as well as high yields, throughout the study. The SI system, characterized by yearly compost amendments, and irrigation, both resulted in higher yields, but also higher levels of black scurf and common scab. Cropping system and irrigation effects were still significant even after systems were no longer maintained. Soil microbial community data, exemplified by FAME profiles, showed significant changes associated with cropping system, and differences among systems increased over time. Overall, cropping system strategy had significant and lasting effects on soil microbiology and soilborne diseases.