Location: Crop Bioprotection Research
Title: Antagonist cryptococcus flavescens OH 182.9 3C colonization of wheat heads when applied with triazole fungicides and the effect on scab Authors
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: May 13, 2013
Publication Date: August 10, 2013
Citation: Schisler, D.A., Paul, P., Boehm, M.J., Bradley, C.A., Dunlap, C.A. 2013. Antagonist cryptococcus flavescens OH 182.9 3C colonization of wheat heads when applied with triazole fungicides and the effect on scab [abstract]. APS-MSA Joint Meeting. 178-P. Technical Abstract: Integrated pest management (IPM) is the best available approach for reducing Fusarium head blight (FHB; caused by <i>Fusarium graminearum</i>) and the mycotoxin deoxynivalenol (DON) in wheat grain. Utilizing FHB biological control agent <i>Cryptococcus flavescens</i> OH 182.9 (NRRL Y-30216) as part of an IPM approach against FHB is understudied. Triazole fungicides such as prothioconazole (PTC) used alone or in combination with tebuconazole are effective against FHB, but minimum pre-harvest intervals for fungicide use can restrict applications after wheat flowering. A PTC-tolerant variant, OH 182.9 3C (NRRL Y-50378), applied in a tank mix with a fungicide or after flowering, could reduce DON by establishing populations that reduce post-flowering DON-producing infections by <i> F. graminearum</i>. In a multi-year study, the colonization of glume and lemma tissues by variant 3C was determined when the agent was applied alone or in combination with a fungicide at wheat flowering or seven days after. For all treatment combinations, the population of 3C represented 50-95% of the total microbial population recovered from both glume and lemma tissues from 8 to 11 days after flowering, demonstrating the competitive success of the strain. While the application of 3C at times reduced (P<0.05, FPLSD) FHB and/or DON, combinations of fungicide and antagonist were rarely significantly more effective than either component used alone for the doses tested.