Seedling infections slow plant growth, but rarely kill the plant. Symptoms generally appear first on the older leaves of young plants as faint yellowish-green blotches near the leaf tip. The blotches enlarge rapidly and merge, changing to shades of red to purple in oats, yellow to red in wheat and bright yellow in barley. The leaves may lose their flexuous appearance and become erect or stiff. The leaf margin near the tip may roll inward and become necrotic forming a stiff point.
Plants infected early are usually dwarfed.
Early fall infection frequently predispose plants to winter killing even if they are symptomless. Plants infected later may develop symptoms only on the leaves actively growing at the time of infections. Infections that occur in the spring may result in discoloration of only the top leaf, or flag leaf. In barley, the most characteristic symptoms are dwarfing and the brilliant yellow coloring of the leaves. Severe dwarfing and yellowing are less common in wheat.