Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/4/2004
Publication Date: 8/4/2004
Citation: Schisler, D.A., Khan, N.I., Boehm, M.J., Zhang, S., Slininger, P.J. 2004. Selection and field evaluation of choline-utilizing microbial strains as potential biocontrol agents of fusarium head blight. Phytopathology (American Phytopathological Society Abstracts). 94:(6):S93.
Technical Abstract: The importance of choline in Fusarium head blight (FHB) development is debatable (Plant Dis. 88:175-180). Choline in wheat anthers can stimulate growth of conidial germ tubes of Gibberella zeae suggesting that choline-utilizing strains (CUS) may be effective competitors of the pathogen. Because combinations of strains can potentially increase the efficacy and consistency of biocontrol, CUS were sought to combine with efficacious FHB biocontrol strain Cryptococcus nodaensis OH 182.9 (NRRL Y-30216). CUS were identified from a microbial collection obtained from wheat anthers. When choline chloride was supplied as a sole carbon source in liquid culture, 122 CUS were identified out of 738 (16.5%) strains assayed using a colorimetric, choline oxidase-based bioassay. Twelve CUS with FHB biocontrol activity in greenhouse assays were selected for field testing. Four of 12 CUS reduced FHB symptoms at 2 sites on 2 wheat varieties. A Gram-positive bacterial CUS AS 54.6 reduced disease severity by 17-60% on Pioneer 2545.