Stripe Rust Reported in the Area

Stripe rust has been observed in winter wheat at the Eastern Agricultural Research Center here in Sidney. The cooler weather and moisture recently have been ideal conditions for the disease. This article will review some information on stripe rust disease and management options at this point in the growing season.

Stripe rust is a fungal disease that is appropriately named, as the disease forms in a linear pattern of yellow-orange powdery pustules along the leaf blade. This disease is polycyclic, meaning that it will continue to produce spores and spread as long as the conditions are favorable. Stripe rust favors cooler and wetter conditions for initial infection and development; temperatures of 50 to 64°F and 6 hours of dew are ideal. Once plants are infected, temperature is less important. The warmer forecast should slow new infection, but it still is important to scout your fields for the disease. The Richland County Extension Office is always available to assist in plant disease diagnosis.

Management options for controlling stripe rust include planting resistant varieties. Fortunately, there are both winter and spring resistant varieties. Results from a 2016 resistance study are shown below. Resistant varieties can show symptoms that appear to be a rust infection; however this is the plant's resistance fending off the pathogen.

The other management option for controlling strip rust is a fungicide application. However, timing of this application is critical, as the key is to protect the flag leaf. If the crop becomes infected later in its development, stripe rust will have less impact on yield. Generally, the last stage to apply a fungicide is flowering, but this is product dependent so be sure to read and follow label directions. There are several fungicides available for controlling stripe rust. Contact the Richland County Extension Office for a list of options. Remember to always read and follow label directions for harvest restrictions for application timing.