Maturity of our winter wheat is well ahead of normal and could have some important consequences on crop yield and management this year. Our wheat lines in Centre County have started heading yesterday May 7 compared to May 26 last year and May 15 in 2010. This will likely mean that wheat could benefit from cooler temperatures during the grain fill period, and perhaps and longer grain fill period and higher yields. The disease situation in wheat in Pennsylvania is critical to monitor. Powdery mildew and Stagonospora have been advancing upward in the canopy in our variety trial recently with the cool wet conditions. With the potential high yields in this years crop, it is important to try to keep these diseases off the top two leaves. There are striking differences among varieties for mildew resistance in our trials so if you are seeing heavy mildew infestations, you may want to reevaluate varieties for next year.
Most wheat is heading and/or flowering and is at or approaching the critical stage for treating for head scab or other diseases if the risk is high. The risk for head scab has been low on the FHB Risk Assessment Tool, but today high risk areas began to appear on our map likely due to the warm and wet conditions this week. There is also some risk of a leaf rust infestation as Kentucky and other southern states have reported rust in many fields and some of those spores could have moved here during the last two weather fronts that moved through. I would be monitoring wheat diseases and planning fungicide applications accordingly. Triazole fungicides such as Caramba and Prosaro have the most activity on Fusarium Head Blight when applied at flowering. These products also provide good control of powdery mildew, leaf blotches and rust when applied then for the critical early grain fill period.
–Greg Roth, Extension Agronomist, Pennsylvania State University
For more details, go to the FHB Risk Assessment Tool at http://www.wheatscab.psu.edu/riskTool_2012.html