Wheat and Barley Disease Updates

Alyssa Koehler, Extension Field Crops Pathologist; akoehler@udel.edu

Overall wheat and barley are looking good across the state. With the warm weather and rainfall expected in the next week, continue to monitor your fields and keep an eye on foliar diseases. Some foliar diseases have begun to show up in lower canopies. As long as lesions have not crept too far up the plant, you can continue to wait and utilize potential fungicide application at the Fusarium Head Blight timing. We have remained at a low risk for our region on the Fusarium Head Blight Prediction Center this week http://www.wheatscab.psu.edu/. As barley gets close to heading, continue to keep track of the risk model and the weather forecast. Remember that application to manage FHB is most effective before barley head emergence and at flowering in wheat. It is best to avoid irrigating during these times to reduce the infection period. If you do plan to make a fungicide application for FHB remember that method of application is another factor to consider. Most fungicides are locally systemic so they protect the tissue where they are applied. Flat fan nozzles pointed 90° down are great at covering foliage but they do not provide good coverage on heads, which is the target for FHB management. Nozzles that are angled forward 30-45° down from horizontal (30 degrees is better than 45) or dual nozzles angled both forward and backward give better contact with the head and increase fungicide efficacy. For ground sprays, fungicides should be applied in at least 10 gallons of water per acre.