Submitted to: International Congress of Pesticide Chemistry Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/11/2014
Publication Date: 8/12/2014
Citation: Stipanovic, R.D., Crutcher, F.K., Liu, J., Bell, A.A. 2014. Can a biological reduce the pathogenicity of the plant pathogen Fusarium oxysporum f. sp. vasinfectum by degrading the phytotoxin fusaric acid? [abstract]. International Congress of Pesticide Chemistry Abstracts. A#750.
Technical Abstract: Race 4 of Fusarium oxysporum f. sp. vasinfectum (Fov) is an emerging problem for cotton production in the U.S. because it is significantly more pathogenic than races 1 and 2 which are endemic to the U.S. Race 4 is a prodigious producer of the phytotoxin fusaric acid compared to races 1 and 2. When the biosynthesis of fusaric acid is blocked in Fov isolates that produce high quantities of fusaric acid, their pathogenicity is significantly reduced. Thus, fusaric acid production appears to be a critical factor in the enhanced pathogenicity of Fov race 4. Isolates of Gliocladium virens are recognized biocontrol agents and have been used to protect cotton from soilborne pathogens. We have established that a Talaromyces species isolated from a Fov infested field as well as other microorganisms can degrade fusaric acid to a compound called fusarinol; the latter is less toxic to cotton than fusaric acid. Talaromyces also has been studied as a biocontrol agent of cotton pathogens. To further investigate the role of fusaric acid in the pathogenicity of Fov race 4, and determine if G. virens or Talaromyces might reduce disease symptoms, we tested these microorganisms for their ability to control the pathogenicity of Fov race 4.