Wheat crops in the flowering stage are now at risk for FHB infection across most of the state, with highest risk in the NW region of MN. Winter wheat either already flowered or is flowering now, while some of the first planted spring wheat is close to flowering.
Risk is highest for susceptible to very susceptible cultivars. The 24-72 hour forecast indicates that the risk will remain or even get higher in the next few days.
When considering the application of a fungicide to suppress FHB, assume that all winter wheat varieties are susceptible to very susceptible to FHB (http://www.ag.ndsu.edu/pubs/plantsci/smgrains/a1196_08.pdf). The spring wheat varieties rate from moderately resistant to very susceptible. The ratings can be found in the Minnesota Variety Trials Bulletin (http://www.maes.umn.edu/10varietaltrials/redspringwheat.pdf)
Disease pressure of other diseases is high for tan spot but low for leaf rust as it appears that little leaf rust inoculum has made it this far north to date. Powdery mildew can readily be found in Lake of the Woods and Roseau counties and central Minnesota.
Fungicides labeled for an application at Feekes 10.51 include Folicur, several generic versions of Folicur, Caramba, and Prosaro. Extensive university studies comparing Prosaro and Caramba fungicides with Folicur show that Prosaro and Caramba provide a 20% better reduction of FHB and a 30% better reduction of vomitoxin than Folicur, when tested on moderately susceptible to susceptible cultivars.
The risk maps of the different diseases, including FHB, for Minnesota can be found at the Minnesota Association of Wheat Grower's Fusarium Heab Blight Forecasting website (http://mawg.cropdisease.com). The website also creates risk maps for tan spot, Septoria leaf blotch, and leaf rust. Access to the national risk map may be found at www.wheatscab.psu.edu/. The NDSU disease forecasting site can be found at www.ag.ndsu.nodak.edu/cropdisease.