Causal Agent: 

Fungus (Physoderma maydis)

Characteristic Symptoms:
 
Symptoms develop on leaf blades and consist of small chlorotic spots, arranged as alternate bands of diseased and healthy tissues.
   
Spots on the mid-ribs are circular and dark brown.
   
Nodes and internodes also show brown lesions.
   
In severe infections, lesions may coalesce which may induce stalk rotting and lodging.
   
Conditions for Disease Development:
 
 The disease occurs in areas of abundant rainfall and high mean temperatures.
   
Management and Control:
 
Use of resistant varieties, if available.
   
Crop rotate with non-host to reduce disease inoculum.
   
Till properly to encourage breakdown of crop residues.
   
 
   

References

https://www.pioneer.com/home/site/mobile/grow/corn/physoderma-brown-spot/

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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