| Two microbial strategies for controlling Fusarium head blight (FHB) and deoxynivalenol (DON) have been developed. A concurrent screening method involving five bioassays was used to select soil and food microorganisms for the ability to suppress Fusarium graminearum and FHB in wheat. Two isolates of Paenibacillus polymyxa reduced disease severity by 56.5 and 55.4%, DON production by 84.8 and 89.4%, and increased 100-kernel weights by 56.6 and 66.9%, respectively. These isolates were characterized for potential mechanisms of action, and assessed for their potential to control FHB in wheat. Six agricultural soils capable of reducing DON were obtained after enrichment using mouldy corn with F. graminearum. These enriched soils reduced DON by more than 87%, and the reduction was associated with biological activity. Identification of DON-transformation products and isolation of DON-transforming microorganisms will be completed in future study. To produce up to 1 g of pure DON for research use, a novel method for purification of DON from F. graminearum rice culture and mouldy corn by high-speed counter-current chromatography was developed. |
