Wheat diseases continue to be at unusually low levels. Septoria leaf blotch is the most prevalent disease and can be found on lower leaves at most locations and moving up the plant at some locations. A few leaf rust pustules and patches of barley yellow dwarf were found at Marianna, and some powdery mildew was found at Newport. No stripe rust has been found anywhere in Arkansas so far.
Septoria leaf blotch appears to have the greatest potential to cause yield loss this year, but damage will depend on the susceptibility of the variety and the weather during the rest of the season. Most varieties have at least some resistance, but leaf blotch can still develop to damaging levels if the weather is favorable. Mild temperatures, frequent rains, windy conditions and high humidity are favorable for leaf blotch. If leaf blotch can be easily found on the lower half of the canopy by boot stage, a fungicide application between boot and heading stages likely would be beneficial. All registered fungicides are more-or-less equally effective. Wheat across Arkansas is at or near boot stage, so now would be an ideal tome to scout for diseases and make a fungicide application if needed.
Thanks to Jason Kelley, Esten Mason and Dave Moon for contributing information for this update.