First in 2005

Gray Leaf Spot disease caused by Pyricularia grisea was confirmed today on perennial ryegrass. The sample came in from an athletic field in the Lancaster area of Ohio.

Outbreaks in Ohio appear to occur following hurricane events when conditions are very humid and warm. It is very difficult to diagnose gray leaf spot as it can be confused with brown patch (Rhizoctonia solani). Gray leaf spot infested leaf tissue will collapse very quickly and has a grayish color. It can also be confused with drought symptoms.

For more information on gray leaf spot, refer to the previous posting (8/25/05). Perennial ryegrass turf managers should be vigilant for this disease right now. If gray leaf spot is suspected, send a sample to OSU's Diagnostic Clinic. For details on how to do this, phone (614) 292-5006, or click HERE

Turf managers with questions about this can call turfgrass pathologist, Joe Rimelspach, (614) 292-9283

Authors: Joe Rimelspach