ARS | Publication request: GRAM NEGATIVE BACTERIA FOR REDUCING PINK ROT, DRY ROT, LATE BLIGHT, AND SPROUTING ON POTATO TUBERS IN STORAGE

Submitted to: Potato Association of America Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: July 27, 2006
Publication Date: July 23, 2006
Citation: Schisler, D.A., Slininger, P.J., Miller, J.S., Woodell, L.K. 2006. Gram negative bacteria for reducing pink rot, dry rot, late blight, and sprouting on potato tubers in storage [abstract]. Potato Association of America Proceedings. Paper No. 004C

Technical Abstract: Pink rot of potato, incited primarily by Phytophthora erythroseptica, is a disease of importance in many potato-growing regions of the world including North America. The primary mode of entry by the pathogen into tubers in storage is via wounds or eyes; surfaces that theoretically could be protected using microbial antagonists. In previous research conducted at the NCAUR, ARS, Peoria, IL, we isolated 18 microbial strains from soils suppressive to dry rot and demonstrated the efficacy of strains of Pseudomonas, Enterobacter, and Pantoea in reducing dry rot (Phytopathology 87:177-183), late blight (Phytopathology 94:S96) and sprouting (Biological Science and Technology 13:477-494) on tubers in storage. United States patents have been obtained regarding the strains and their use. However, these strains have not been tested for efficacy against pink rot until now. Ten of these strains were grown in a semi-defined liquid medium at 25 degrees C for 48 hours, diluted to a concentration of approximately 3 x 10E+8 cfu/ml, individually combined with sporangia of Pseudomonas erythroseptica, and the mixed microbial suspension used to inoculate shallow puncture wounds on tubers of cultivars Russet Burbank and Russet Norkotah. Preliminary results indicate that several of these strains reduce pink rot under bioassay conditions and that potato cultivar may influence the relative efficacy of individual biocontrol strains. The possible role of these strains as part of an integrated management program to reduce potato storage maladies will be discussed.