LEAF DISEASES ON WINTER WHEAT, WILLIAMSON COUNTY
The attached short video identifies two leaf diseases of winter wheat in a field near Hutto. The fungal lesions of tan spot infected early during the tillering stage of wheat and slowly spread up to the flag leaf stage. A light infestation of Leaf Rust was observed as small clusters of lesions on the flag-1 leaf stage and did not spread much beyond this very light infection. Our wet conditions during late winter/early spring did not favor the spread of leaf rust.
Overall, leaf diseases were not significant problem this past winter.
Gary Pastushok CEA – AG
WHEAT HEAD DISEASES 2020 – WILLIAMSON COUNTY
The attached video shows details of three most common head diseases of winter wheat that I found this past spring.
Of the three fungal diseases of wheat, two of the diseases are from foliar infections and one is derived from infested seed. The foliar diseases are Fusarium head blight (Fusarium graminearum) and Septoria glume blotch (Septoria tritici). Because corn is an alternative host for Fusarium, it is basically impossible to rotate away from this disease as infected corn stubble houses the pathogen.
Septoria can infect from airborne spores and infected wheat residues in the area. Both Fusarium and Septoria can be managed by fungicide use.
Loose smut (Ustilago tritici) is seed borne and only controlled by using seed treatments. I had observed two fields with significant numbers of smut infested heads. From a disease management perspective, holding wheat seed containing high amounts of smut infection will produce more diseased plants at the next planting – reducing crop yields.