Gary Bergstrom, Extension Plant Pathologist, Cornell University
Winter wheat in much of New York State is at the flag leaf emerged to boot stages of development and heads will emerge over the next week. Heads have already emerged in warmer regions of the Hudson Valley. The next 14 days will be critical for farmers making fungicide spray decisions for suppression of Fusarium head blight (FHB) and protection of flag leaves from foliar diseases. The triazole products Caramba, Prosaro, and Proline are the most effective fungicides for suppression of FHB and deoxynivalenol (DON) toxin contamination when applied at wheat flowering (emergence of anthers on heads). A flowering application of triazole fungicide should be based on Fusarium head blight (FHB) risk as well as the risks of powdery mildew, rust, and fungal leaf blotches in the upper canopy based on scouting of individual fields. There is an application window of approximately 5-6 days from the beginning of flowering in which reasonable FHB suppression can be expected. Fungicide products containing strobilurins should not be applied to headed wheat as they may result in increased levels of DON in grain. The forecast over the next several days is for cool weather that will slow development of Fusarium spores in the region. But the extended forecast for the final days of May into early June calls for a warming trend with significant chances for precipitation. Check the Fusarium Risk Assessment Tool (http://www.wheatscab.psu.edu/) and your local weather forecast frequently as your crop approaches flowering.
Receive FHB Alerts by Cell Phone:
I will be providing weekly New York commentaries on FHB risk through mid-June. You can subscribe to receive FHB Alerts directly to your Cell Phone (http://scabusa.org/fhb_alert.php). You can select to receive alerts as 1) Text Message Alerts, 2) Email Alerts, or 3) both Text and Email Alerts. To receive alerts for New York, select the Northern Soft Winter Wheat option which provides alerts for MI, NY, WI and VT.
