Volunteer wheat has tested positive for wheat streak mosaic virus in Hodgeman, Mitchell, Republic, and Smith counties. These samples were collected as part of a statewide volunteer wheat (and other grass host) survey we have been conducting in response to the wheat streak complex outbreak in 2025. Although testing for other counties is still in progress, this is an important reminder that volunteer wheat control is the most important defense against wheat streak mosaic as we head into wheat planting this fall (Figure 1).
Figure 1. Volunteer wheat images from September 2025 in Kansas. Photos by Kelsey Andersen Onofre, K-State Research and Extension.
Free lab testing for the Wheat Streak Mosaic Virus Complex
Would you like to test your volunteer wheat or other grasses for the wheat streak mosaic virus complex? The Plant Pathology Department is offering free testing over the next several weeks. This will help us understand where these viruses survive over the summer and the risk going into fall wheat planting. Here are some reminders for collecting a good sample:
- Each sample should consist of at least 5 entire plants/field, including roots. Plants should be green and in good condition for virus testing.
- Carefully remove excess soil from the roots (no soil is preferred) to avoid damaging the plants.
- Place each sample in a plastic bag for storage and transport. Keep cool until shipping.
- Label the sample bag with the sample field ID
- Fill out the submission form with as much information as possible. Include variety/hybrid info (especially for wheat). Attach it to the outside of the sample bag.
- Ship samples overnight to the Diagnostic Laboratory (address is located on the submission form linked above) to ensure freshness and avoid deterioration during transit. Use FedEx or UPS, not USPS.
Additional shipping information can be found here: https://www.plantpath.k-state.edu/extension/plant-disease-diagnostic-lab/
As a reminder, we took a deep dive into wheat streak mosaic biology and management in this past eUpdate issue: https://eupdate.agronomy.ksu.edu/article/wheat-streak-mosaic-complex-webinar-and-management-resources-now-available-654-8
Kelsey Andersen Onofre, Extension Wheat Pathologist
andersenk@ksu.edu
Tags: Plant Disease Diagnostic Lab volunteer wheat wheat streak mosaic