How to Manage Pests

UC Pest Management Guidelines

Small Grains

Leaf Blotch of Oats

Pathogen: Pyrenophora avenae

(Reviewed 2/07, updated 2/07)

In this Guideline:


This disease appears as reddish tan leaf blotches that are somewhat linear with irregular margins. Heavily infected leaves die. Seedling blight may occur if coleoptiles are infected.


The fungus survives on infected, undecayed plant debris in soil or less commonly inside the hull of infected seed. The disease is favored by cool and rainy weather.


No specific control is necessary in California. Practices that control other diseases, such as the use of clean seed, crop rotation, and elimination of crop residue, help control leaf blotch as well.


[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Small Grains
UC ANR Publication 3466


R. M. Davis, Plant Pathology, UC Davis
L. F. Jackson, Agronomy, UC Davis

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