NCLB – Northern Corn Leaf Blight
Scientific Name: Exserohilum turcicum
Type: Fungus
Northern Corn Leaf Blight is a fungal disease that affects the growth of corn. Northern corn leaf blight occurs commonly in the Midwestern regions of the United States. Symptoms are cigar-shaped or elliptical shaped gray-green lesions on the leaves that range from 1 to 7 inches long. Lesions begin on the lower leaves and then spread to upper leaves. Severe symptoms can progress rapidly, resulting in blighted leaves. Lesions can also be found on the husk of ears or the leaf sheaths. It can cause significant yield loss in corn. Losses are greater and more severe when plants are infected at the early stage of growth. The disease will spread by rain or wind. The disease is favorable when temperatures are 64-81 F and usually occur when moisture and humidity are very high. Plants usually become infected when water is present on the leaf surface for 6 to 18 hours. Plan on using a 3 year crop rotation and avoid planting in the same location, year after year, as the disease can survive in over winter on corn leaf debris. Proper tillage practices may be helpful in managing the disease. Fungicides can help manage the disease. The best option is to use hybrid disease resistant varieties.