The use of a well-timed fungicide application can help protect spring barley, durum, and hard red spring wheat (HRSW) from Fusarium head blight (FHB) and deoxynivalenol (DON). With funding from the U.S. Wheat and Barley Scab Initiative, six fungicide trials were conducted in 2022 in North Dakota. The primary objective was to compare the timing and efficacy of fungicide premixes on reducing FHB and protecting yield. Research sites were established at the Langdon Research and Extension Center (Langdon; mist irrigated), Williston Research Extension Center - Nesson Valley (Nesson Valley; linear pivot), North Central Research and Extension Center (Minot; dryland), and North Dakota State University (Davenport and Fargo; dryland). Trial locations were as follows; one barley trial each in Fargo and Davenport, one durum trial each in Nesson Valley and Minot, one HRSW trial each in Langdon and Fargo. Trials were conducted in a randomized complete block design with four to five replications. All plots were sown with a susceptible cultivar relative to the target grain. Fungicides evaluated included Prosaro® (prothioconazole + tebuconazole), Caramba® (metconazole), Miravis Ace® (propiconazole + pydiflumetofen), Prosaro Pro® (prothioconazole + tebuconazole + fluopyram), Sphaerex® (metconazole + prothioconazole), and Folicur® (tebuconazole). Fungicide timings evaluated in barley included Feekes 10.5 (full-head) and 3 to 7 days after Feekes 10.5. For durum and HRSW, Feekes 10.51 (early-anthesis) and 3 to 7 days after Feekes 10.51. When appropriate, FHB, DON and yield data from each location/grain class was combined for analysis. Disease was low to moderate at five of the six locations. All fungicide treatments provided significant reduction of FHB in spring two-row barley, durum, and hard red spring wheat. The greatest amount of FHB suppression, lowest DON levels, and highest yield responses often included treatments with two fungicide applications with one occurring at FGS 10.51 (durum and HRSW) or FGS 10.5 (spring barley) and a second application occurring 3 to 7 days later. The recently labeled fungicide premixes of Prosaro Pro® and Sphaerex® provided similar to sometimes better control than the industry standards of Prosaro® and Caramba®.

ACKNOWLEDGEMENT AND DISCLAIMER

This material is based upon work supported by the U.S. Department of Agriculture, under Agreement Nos. 59-0206-4-012 and 59-0206-8-199. This is cooperative project with the U.S. Wheat and Barley Scab Initiative. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the authors and do not necessarily reflect the view of the U.S. Department of Agriculture.