Submitted to: National Fusarium Head Blight Forum Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 12/15/2003
Publication Date: 12/15/2003
Citation: Zhang, S., Schisler, D.A., Boehm, M.J., Slininger, P.J. 2003. USDA-ARS, Ohio State University cooperative research on biologically controlling fusarium head blight 2: Effects of carbon-to-nitrogen ratio of production media on the biocontrol efficacy and the survival. In: Proceedings of the National Fusarium Head Blight Forum, December 12-15, 2003, Bloomington, MN. p. 116-119.
Technical Abstract: Fusarium head blight (FHB), caused by Gibberella zeae, is a devastating disease of wheat world wide. Cryptococcus nodaensis OH 182.9 has been evaluated as an effective biocontrol agent for FHB. Development of a dried product of OH 182.9 would have potential advantages of ease of handling, favorable economics, and acceptance by end users. OH 182.9 was grown in semidefined complete liquid media (SDCL) with C/N ratios of 6.5, 9, 11, 15, and 30 for 48 and 72 h. Survival of freeze-dried cells was greatest for cells grown in SDCL C/N 30 medium for 48 h. Cells produced in C/N 6.5 medium exhibited the poorest survival. Cells harvested after 48 h were generally more tolerant to freeze-drying than those cultured after 72 h. OH 182.9 produced in C/N 9, 11, and 15 media for 48 h significantly reduced the FHB disease severity compared to the disease control. For the medium C/N 30, research on influence of carbon loading in production media on cell survival after freeze-drying and the biocontrol efficacy against FHB was conducted. Total carbon loading of 7, 14, 21, and 28 g/L in SDCL C/N 30 medium was tested. Cells produced in C/N 30 media with 7, 14, and 21 g/L carbon and harvested after 48 h had better survival than others, including the standard 48 h C/N 11 culture with 14 g/L carbon. OH 182.9 grown in SDCL C/N 30 with carbon loading of 7 or 14 g/L was effective against FHB.