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Description and Symptoms
 Look for symptoms of Septoria leaf blotch when prolonged periods of damp weather occur. The disease may affect plants at any stage of development under a wide range of temperatures.
Symptoms are water-soaked or yellowish spots or specks that first appear on the lower leaves.
Large areas of leaves may be affected. Symptoms spread to upper foliage and glumes if wet conditions persist.
As lesions develop, dark specks appear in their centers. The specks are a key diagnostic feature of Septoria leaf blotch.
Septoria survives on infected crop residue, volunteer grain and seed.
Spores are produced on the surface of infected stubble or crop residue under damp conditions.
Splashing water or wind move spores to the surfaces of leaves. Spores begin V to germinate and infect if the leaf surface remains continuously wet for at least 6 hours.
Greater infection occurs when foliage remains wet for two or three days.
Integrated Management
Plant resistant cultivars when available. Early maturing cultivars are more susceptible in some regions.
Manage crop residue to minimize inoculum after serious infestations.
Rotate crops to limit inoculum survival.
Manage crop to limit excessive vegetative growth (i.e., proper fertilizer).
Apply foliar fungicides when Septoria leaf blotch outbreaks threaten to infect the flag leaves.
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