9/8/2020

Field Facts: Stripe Rust

Stripe rust, also known as yellow rust, is a disease caused by a fungus called Puccinia striiformis and commonly found in wheat. This disease can be found across much of the country, with appearances as early as January in Missouri and other states in the Midsouth.

Symptoms — Early symptoms include small, yellow flecks or spots appearing/arranged in linear rows (yellow streaks) on leaves. As the disease progresses, those flecks develop into elongated lesions/streaks (similar to stripes) of bright, yellow-orange spores.

Geography — Stripe rust can be found across the globe, including on wheat acres in the Midwest and Midsouth.

Timing — Late winter to midspring

Conditions for development — Cool, wet and humid weather. Temperatures between 45 to 54 F favor pathogen infection with peak disease development occurring between 50 and 65 F.

Scouting tips — Fungus spores can survive in wheat plants over winter and tend to clump during humid winter weather. Wind will spread those clumps relatively short distances to other plants. Look for early signs and scout often when weather conditions are right. You can also track when rust develops in states to the south to time when it could move into your area.

Effect on yield — It’s possible for stripe rust to cause 100% crop loss when there is cool, wet weather early in the season and disease progresses to the spikes.

Management tips — Choose seed treatments and resistant varieties. Good weed control can also help prevent disease. Apply a fungicide preventively and, if necessary, curatively. DuPont™ Aproach® Prima fungicide is very effective at controlling stripe rust with preventive and curative modes of action. Learn use rates of the fungicide in wheat.

Aproach® is not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Contact your local Corteva Agriscience sales representative for details and availability. Always read and follow label directions.