ARS | Publication request: Suppression of Rhizoctonia Disease of Potato by Biological Control and a Ryegrass Rotation

Submitted to: National American Phytopathology Meetings
Publication Type: Abstract Only
Publication Acceptance Date: May 30, 2002
Publication Date: June 30, 2002
Citation: Larkin, R.P., Talbot, M.M. 2002. Suppression of rhizoctonia disease of potato by biological control and a ryegrass rotation. National American Phytopathology Meetings. 92: S80

Technical Abstract: Rhizoctonia solani is an important fungal pathogen of potato capable of reducing tuber yield and quality. Integrated, sustainable control options, including effective crop rotations and biocontrol, are needed to reduce pathogen losses. The use of ryegrass as a rotation crop was compared with barley, clover, and no rotation in greenhouse tests for effects on inoculum levels and disease suppression. Early results indicate that ryegrass treatments are more effective than clover at reducing disease. Biocontrol organisms, including Trichoderma spp., Paenibacilllus polymyxa, Penicillium spp., Waitea spp., Pseudomonas fluorescens, Burkholderia cepacia, Bacillus subtilis, Verticillium biguttatum, Laetisaria arvalis and Cladorrhinum foecundissimum, were also screened for disease reduction in greenhouse experiments. Efficacy of the rotation crops alone and in combination with selected biocontrol organisms is being evaluated for reduction of Rhizoctonia inoculum and disease of potato in ongoing field trials at two locations in Maine. Efficacy and interactions among treatments will be discussed.