|Kleinkopf, G - UNIV OF IDAHO|
|Ostrowski, R - UNITED AGRI PRODUCTS|
Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 31, 1996
Publication Date: N/A
Technical Abstract: Control of Fusarium dry rot of stored potato tubers is difficult without effective chemicals for postharvest use on processed and table stock tubers. Biological control of dry rot incited by Fusarium sambucinum (teleomorph=Gibberella pulicaris) has been demonstrated (Plant Dis. 78:251-255). Several Gram-negative bacterial strains that ranked high in both efficacy and amenability to production in liquid culture were selected for pilot studies at the UIKREC. In the first year's study, ~1 x 10**8 cfu/ml of fluorescent Pseudomonas strain S22:1:T:04 decreased the level of dry rot when coinoculated with the pathogen compared to a buffer control and the fungicide Mertec 340F. In second year studies, ~4 x 10**8 cfu/ml of P. fluorescens strain P22:1:Y:05 and Enterobacter cloacae strain S11:3:T:06 controlled F. sambucinum (25% and 17% avg disease decrease, respectively) but not F. coeruleum when antagonists were applied 24 h after pathogen inoculation. Mertec 340F did not control Fusarium, possibly due to strain resistance. Biological control of Fusarium dry rot is approaching commercial reality.