University of Nebraska-Lincoln
Institute of Agriculture and Natural Resources
CROPWATCH
Figure 1. (left) Typical symptoms of Holcus spot caused by Pseudomonas syringae pv syringae: light tan to white round spots that look similar to minor damage from herbicide drift from cell membrane disruptors, such as gramoxone (like Paraquat). (right) More severe symptoms of Holcus spot. It is important to not mistake this disease for a fungal leaf disease as fungicides will not be effective against this bacterial pathogen.
The following diseases were reported in samples submitted to the UNL Plant and Pest Diagnostic Lab June 15 to June 27.
Wheat
East District – Septoria leaf spot, leaf rust, stripe rust, bacterial stripe/black chaff
Southwest District – Wheat streak mosaic virus, Septoria leaf spot, leaf rust, bacterial stripe/black chaff
Northwest District – Wheat streak mosaic virus, Septoria leaf spot, leaf rust
Figure 1. Reporting districts
Soybean
East District – Pythium damping off
Southeast District – Rhizoctonia damping off
Central District – Rhizoctonia damping off
Corn
Southwest District – Holcus spot
East District – Pythium damping off
Southeast District – Rhizoctonia damping off, Holcus spot
Central District – Fusarium crown and stem rot damping off
South District – Fusarium crown and stem rot, Bacterial leaf streak, common rust, Holcus spot
Hops
East District – Downy mildew