Rotate with crops such as oat, flax or legumes. Fungicide seed treatments also are available for suppression of common root rot. Recently released barley varieties have good resistance. Spring wheat and durum are affected to a lesser extent. Fungus spores produced on crop residue are carried by air currents to the leaves.
Infections appear as dark, chocolate-colored blotches.
The spots merge, eventually forming irregular dead patches on the leaves. Heavily infected leaves dry up completely, and infections on the flag leaf during kernel filling are the most serious. Fungicides can be used on varieties that are more susceptible. Rotate with crops such as oat, rye, legumes or flax to reduce source of fungus spores from residue. Most current barley varieties are susceptible.