Eyespot of Corn
Published: 01/27/2022
Eyespot is caused by the fungus Aureobasidium zeae. The initial symptoms of eyespot are small, water-soaked or chlorotic circular spots. The tissue at the center of the spot later dies and turns tan-colored with a brown ring at the margin. The spot is surrounded by a yellow "halo" that can be seen clearly when the leaf is lighted from behind. Spots may join together into large necrotic areas and the entire leaf may die. The spots remain visible even after the leaf dies.
The disease is more common when corn follows corn. Cool temperatures (60s°F to low 70s°F) favor disease development; thus, eyespot may appear early in the season on lower leaves and again near the end of the season on upper leaves.
Eyespot lesions on corn leaf.
Image: A. Robertson
Backlit eyespot lesions showing yellow "halo."
Image: A. Sisson
Resistant hybrids and inbreds are available. Crop rotation and tillage reduce survival of the fungus. Foliar fungicides labeled for eyespot are available.
Backlit eyespot lesions showing yellow 'halo.'
Backlit eyespot lesions showing yellow 'halo.'
Eyespot lesions on corn leaf.
Tissue at the center of an eyespot lesion dies and turns tan-colored with a brown ring.
Eyespot lesions may join together into large necrotic areas and the entire leaf may die.
Eyespot lesions on corn leaf.
Initial symptoms of eyespot are small, water-soaked or chlorotic circular spots on leaves.
Gallery Images: A. Sisson, D. Mueller, and A. Robertson
This publication was developed by the Crop Protection Network, a multi-state and international collaboration of university/provincial extension specialists and public/ private professionals that provides unbiased, research-based information to farmers and agricultural personnel.
This information in this publication is only a guide, and the authors assume no liability for practices implemented based on this information. Reference to products in this publication is not intended to be an endorsement to the exclusion of others that may be similar. Individuals using such products assume responsibility for their use in accordance with current directions of the manufacturer.
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD).
USDA is an equal opportunity provider and employer.
©2022 by the Crop Protection Network. All rights reserved.
