Gary Bergstrom, Extension Plant Pathologist, Cornell University
Heads have emerged and flowering has begun or will soon begin for most of the winter wheat and winter barley crops in New York State. This is a critical time for assessment of disease risk and for making a decision to apply an effective triazole fungicide, i.e., Caramba, Prosaro, or Proline, for suppression of Fusarium head blight (FHB), reducing the risk of deoxynivalenol (DON) contamination of grain, and protection of flag leaves from foliar diseases. The Fusarium Risk Assessment Tool (http://www.wheatscab.psu.edu/) currently projects a low risk of FHB infection, but this could change as warm, humid conditions with scattered showers are forecast through this weekend. The extended forecast through the early grain-filling period calls for above-normal temperatures and precipitation that could favor development of fungal foliar diseases that are currently at low levels. There is an application window of approximately 5-6 days from the beginning of flowering (Feekes 10.5 in barley and Feekes 10.5.1 in wheat) in which reasonable FHB suppression can be expected.
