Some wheat fields in eastern Nebraska have been affected by Fusarium head blight (scab) due to rains occurring before and during flowering. Incidence and severity of the disease vary from trace to moderate and some fields or parts of fields are more affected than others.
Growers are advised to inspect their fields for scab.
Scab causes premature bleaching of heads (spikes) of small grain cereals. In wheat, the bleaching starts with one or more spikelets on a head and can continue until the entire head is bleached. The color of the bleached heads varies with wheat cultivar and can range from white to brown. In a disease-favorable growing season, numerous spikes can be seen randomly scattered in the field.
Bleached spikelets are sterile or contain shriveled and/or chalky white or pink kernels known as Fusarium-damaged kernels (FDK), scabby kernels, or “tombstones”. Kernels that appear to be healthy also may be infected, especially if infection occurred late in kernel development. Infected kernels contain mycotoxins, primarily deoxynivalenol (DON).
If moderate to high levels of scab are found, the following strategies can be used to handle scabby grain: