| Characteristic Symptoms: | |
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Symptoms of southern corn leaf blight depends on what race of the pathogen is present. |
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Race 0 is common in sub-tropical and tropical areas. |
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Spots of Race O are tan in color with brown borders. |
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Lesions begin as small, diamond-shaped lesions and elongate within the veins to become larger and rectangular. |
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Race O's lesions remain within the leaves of the maize plant. |
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Lesion size ranges from 2 to 6 millimeters wide and 3 to 22 millimeters long. |
| Conditions for Disease Development: | |
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The fungus overwinters in corn debris and on seed. |
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Wind and splashing water spread the spores rapidly in the field under ideal conditions. |
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SCLB disease is prevalent in hot and humid corn growing areas. |
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B. polaris requires slightly higher temperatures for infection than H. turcicum |
| Management and Control: | |
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Use resistant varieties, if available. |
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Crop rotate with non-host to reduce corn residues and disease inoculum. |
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Apply fungicides such as pyraclostrobin+dimetomorph (e.g. Cabrio®), azoxystrobin (e.g. Amistar®) or propiconazole (e.g. Bumper®, Tranzole ®). |
| References: | |
| https://en.wikipedia.org/wiki/Southern_corn_leaf_blight | |
| The CIMMYT Maize Program. 2003. Maize Diseases: A Guide for Field Identification. 4th edition. Mexico, D.F.: International Maize and Wheat Improvement Center (CIMMYT). | |
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