Time for concern: Whorl through tassel
Key characteristics: Long elliptical, grayish green or tan lesions ranging from 1 to 5 inches in length, develop on the lower leaves first, and then progress to younger tissue. Lesions often look “boat shaped.” This disease has increased in importance in the northeast.
- A Checklist of Sweet Corn Diseases and Suggested Control Measures
- Northern corn leaf blight on sweet corn
Fungicide sprays may be needed for fresh market sweet corn, hybrid seed production, and dent corn fields planted with susceptible hybrids. The following recommendations are from Ohio: The spray schedule should start when the first lesions appear on the leaf below the ear on 50% of the plants. Applications made at tasseling or silking (VT/R1) provide the most consistent results in terms of disease control and yield response.
|Resistant varieties||Plant resistant varieties whenever possible. See Section 26.1 Recommended Varieties.|
Plant only in fields where sweet or field corn was not grown in the previous year.
|Site selection||Avoid fields with poor air drainage.|
|Postharvest||Crop debris should be destroyed as soon as possible to remove this source of disease for other plantings and to initiate decomposition.|
|These are not currently viable management options.|
|Pesticides||Cornell Integrated Crop and Pest Management Guidelines for Commercial Vegetable Production|