University of Illinois

No. 17/July 16, 1998

Gray Leaf Spot of Corn

In last week's issue, I included an article from the Kentucky Pest News on gray leaf spot (GLS). Since then, I have been contacted by Paul Klemme, Tilt product specialist with Norvartis, asking that I clarify certain points in that article.

According to the Tilt label, this product can be applied to field corn, field corn grown for seed, sweet corn, and popcorn to control gray leaf spot, other leaf blights, rust, and eyespot. For GLS and eyespot control, apply 4 oz. per acre when disease first appears and repeat on a 14-day schedule. Do not apply after silking (after half of the plants are showing silks), do not apply more than 16 oz. per acre per season, do not apply to sweet corn within 14 days of harvest, do not harvest corn for forage within 30 days of application, and do not harvest sweet corn for forage for forage within 14 days of application.

For aerial applications, use a minimum of 5 gallons of water per acre. For ground application, use a minimum of 20 gallons per acre. Maintain pump pressure at 35 to 40 psi at the nozzles and provide sufficient agritation in the tank to keep the mixture in suspension.

H. Walker Kirby (, Extension Plant Pathology, (217)333-8414