Wheat Diseases

All Wheat Diseases Content

Three wheat fields exhibiting wheat streak mosaic virus symptoms throughout.

South Dakota Wheat Streak Mosaic Virus Disease: 2026 Update

Wheat streak mosaic virus is on the move across South Dakota wheat fields. Due to the mild winter and overwintering in winter wheat, viral activity has had a jump start in 2026, and the occurrence and intensity of disease pressure is comparable to the 2025 season.

wheat field

Wheat

The SDSU Extension team provides unbiased, research-based information to help wheat growers make decisions to improve yields and profits.

aerial view of South Dakota farm and surrounding land

Crops

During the growing season, SDSU Extension provides weekly production recommendations.

Color-coded map of South Dakota showing Fusarium head blight risk throughout the state. For a detailed description, please call SDSU Extension at 605-688-4792.

Tools Available for Fusarium Head Blight Prediction

Fusarium Head Blight (FHB), commonly known as scab, is a major disease threat for wheat each year during the flowering growth stage. To support growers in making informed fungicide decisions, forecasting tools are available that use weather data to estimate the likelihood of scab development.

Wheat plants in a field showing viral symptomology of Wheat Streak Mosaic Virus.

Wheat Streak Mosaic Virus Confirmed in 2026

At the end of April, a winter wheat sample was submitted to the Plant Diagnostic Clinic displaying typical viral symptoms of chlorosis and streaking. Upon testing, this sample was determined to be positive for Wheat Streak Mosaic Virus.

grass leaves with yellow and brown streaking on the tops and edges

Grass Diseases of South Dakota Identification Guide

Common grass disease identification guide.

a person holding a leaf that has yellow, brown and green streaking.

Bacterial Leaf Streak in Wheat Varieties Adapted to South Dakota

Research trial results for Bacterial Leaf Streak tolerance in winter and spring wheat varieties grown in a disease nursery near Volga, South Dakota.

sun rising over South Dakota field

South Dakota Pest Management Guides

The South Dakota Pest Management guides are now available for free. The guides offer recommendations for controlling weeds, insects, and diseases in a variety of South Dakota crops.

People stand in a field listening to a person speak

SDSU Extension programs help producers maintain healthy crops

August 26, 2025

Madalyn Shires puts on a lot of miles in the summer. As an assistant professor and SDSU Extension Plant Pathology Specialist, Shires traverses the state visiting research plots and educating crop producers on that research.

Coneflower with Aster yellows disease.

Aster Yellows Phytoplasma

Aster yellows is a phytoplasmal disease carried and introduced by aster leafhopper. It is known to infect over 80 different plant families, as the aster leafhopper has extremely broad feeding habits.