Corn: Eye Spot (Aureobasidium zeae)

Pub 812: Field Crop Protection Guide > Chapter 1: Corn > Eye Spot

Field Crop Protection Guide 2011-2012, Order 2011-2012 publication

Table of Contents

  1. Description
  2. Integrated Pest Management Options
  • pyraclostrobin - Headline EC
  • azoxystrobin + propiconazole - Quilt
  • propiconazole - Tilt 250 E, Bumper 418 EC
  • prothioconazole - Proline 480 SC
  1. Related links...


Description

The disease produces characteristic round or oval spots (1-4 mm (1/16-1/8 in.)) with a tan/brown centre and a brown or purple margin. A translucent yellow halo forms around the margin, and when held to the sun, the lesions resemble an eye. Leaf blighting may occur when these lesions join, killing large portions of leaf tissue. The disease may be confused with non-infectious physiological leaf spots or insect damage.

Image 1. Eyespot causes round or oval leaf spots with a tan/brown centre, a brown or purple margin, and a translucent yellow halo when held up to the sun.
Image 1. Eyespot causes round or oval leaf spots with a tan/brown centre, a brown or purple margin, and a translucent yellow halo when held up to the sun.

Integrated Pest Management Options

Many resistant or tolerant commercial hybrids are available. Consult with your seed company and the Ontario Corn Committee Hybrid Performance Trials at www.gocorn.net for hybrid selection. Crop rotation and tillage will reduce inoculum levels in surface residues. In reduced tillage systems, rotation and resistance are necessary. Chemical control is usually not economical in field corn but may be necessary if a very susceptible seed corn inbred is used.

 
Active ingredient pyraclostrobin
Trade name Headline EC
Rate per hectare (product) 400-600 mL per ha
Rate per acre (product) 160-240 mL per ac
PHI* 7
Comments Ground and aerial application. Use a minimum water volume of 100 L/ ha. For optimal disease control, begin applications prior to disease development. Do not graze treated crop within 6 days of last application. Maximum 2 applications/yr. 12-hr re-entry period.

 

 
Active ingredient azoxystrobin + propiconazole
Trade name Quilt
Rate per hectare (product) 0.75-1.0 L per ha
Rate per acre (product) 305-406 mL per ac
PHI* 30
Comments Ground and aerial application. Apply when disease first appears, followed by a second application 14 days after, if environmental conditions are favourable for disease development. Do not apply to field corn or field corn grown for seed after brown silk. Maximum 2 applications/yr.

 

 
Active ingredient propiconazole
Trade name Tilt 250 E
Rate per hectare (product) 500 mL per ha
Rate per acre (product) 200 mL per ac
PHI* 14
Comments Ground and aerial application. Apply when rust pustules first appear. Under severe disease pressure, a second application 14 days later may be necessary. Only in seed corn, under severe disease pressure can a third application be made 14 days later. Can be tank mixed with Ripcord or Matador insecticide for insect control.

 

 
Active ingredient propiconazole
Trade name Bumper 418 EC
Rate per hectare (product) 300 mL per ha
Rate per acre (product) 121 mL per ac
PHI* 14
Comments Ground and aerial application. Apply when rust pustules first appear. Under severe disease pressure, a second application 14 days later may be necessary. Only in seed corn, under severe disease pressure can a third application be made 14 days later. Can be tank mixed with Ripcord or Matador insecticide for insect control.

 

 
Active ingredient prothioconazole
Trade name Proline 480 SC
Rate per hectare (product) 420 mL per ha
Rate per acre (product) 170 mL per ac
PHI* 14
Comments Ground application only. Maximum 1 application/yr. 24-hr re-entry period.

 

Related links...

 


For more information:
Toll Free: 1-877-424-1300
Local: (519) 826-4047
E-mail: ag.info.omafra@ontario.ca
Author: OMAFRA Staff
Creation Date: 2 May 2011
Last Reviewed: 10 May 2011