|Van Cauwenberge, James|
Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 7/31/2002
Publication Date: N/A
Technical Abstract: Cryptococcus nodaensis OH 182.9 reduces Fusarium head blight (FHB) of wheat in greenhouse and field environments. Protocols were developed for scaling-up biomass production in 100-L fermentors, processing biomass using continuous flow centrifugation and storing the biomass as a frozen concentrated paste for subsequent field evaluation at 15 sites across the U.S. in 2001. The current studies were initiated to determine the feasibility of freeze-drying biomass to enhance product stability and maintain biocontrol efficacy. Adding turanose (a disaccharide) and melezitose (a trisaccharide) to liquid culture broth enhanced OH 182.9 survival initially and over time compared to six other cryoprotectants. Melezitose increased the survival of dried OH 182.9 by as much as 2 log units [5 x 10(8) vs 5 x 10(6)/CFU/ml] after 14 days if it was incorporated at 10 to 100 mM at the onset or terminus of biomass production in shake flasks. Cryoprotectants alone occasionally increased FHB. The efficacy of biomass of OH 182.9 produced in a 100-L fermentor and freeze-dried in a 24-L capacity dryer will be presented.