Scouting for winter wheat diseases was done in Davison, Douglas, Brule, Charles Mix, Lyman, Aurora, Hughes, Hand, Kingsbury and Brookings counties over the last week. Leaf rust was found in Davison, Lyman, Hughes, and Brooking counties. Stripe rust was found in Brookings, Lyman, Brule and Charles Mix counties while stem rust was found only in Brookings County.
Stripe and leaf rusts were found to be at trace levels in all fields that were found with these rusts. Stem rust in Brookings County was found only on the Robidoux cultivar (susceptible to common stem rust races in the Great Plains region) in the screening nursery at moderate severity (Fig. 1). Stripe rust (also called yellow rust) causes yellow, blister-like lesions that are arranged in stripes (hence the name) (Fig. 2). Leaf rust (also known as orange rust) causes small, orange-brown blister like lesions on leaves (Fig. 3). Stem rust (also called black rust) has reddish-brown color pustules and these cause tearing as they burst through the outer layers of plant tissues (Fig.1). The stem rust can occur on leaf sheaths, leaves, and stems.

Fig. 1. Stem rust on Rubidoux cultivar in the winter wheat nursery at Brookings on June 30, 2013.