Ascochyta Leaf Blight

Hosts, Symptoms & Signs

• affects all species of grass
• leaves die back from the tip, resulting in brown patches of grass
• does not cause permanent damage
• symptoms can occur at any time but are more commonly seen during hot, dry weather
• top third of leaf blade dies back, and the area between diseased and healthy tissue is slightly constricted
• fruiting structures develop on dead grass blades

Disease Cycle

• overwinters in plant debris and thatch
• spores are released from fruiting structures during wet weather and are dispersed by splashing water and lawn mowers
• infections occur on the newly cut end of the grass blade

IPM Recommendations

• Reduce thatch with proper cultural practices.
• Improve water penetration by aerification.
• Maintain sharp mower blades to reduce wounding of grass; reduce mowing frequency during an outbreak.
• Implement a balanced fertilizer program; avoid excessive nitrogen, especially in the spring.
• Avoid drought stress as well as excessive irrigation.