Causal Agent: 

Fungus (Stenocarpella macrospora syn Diplodia macrospora)

Characteristic Symptoms:
 
On stalk, oval, irregular or elongate lesions with pale cream-brown centres and indeterminate darker borders are formed.
   
On leaves, diamond shaped brown lesions are formed.
   
On ear, early infections result in bleached or straw-coloured husks. Inner husks adhere tightly to one another or to the ear due to mycelial growth in between. Black pycnidia may be formed.
   
Conditions for Disease Development:
 
Unbalanced fertility, low K, poor drainage, mechanical and insect damage, cultivar and planting density all influence disease severity.
   
Management and Control:
 
Use fungicide-treated seeds.
   
Avoid low K and high N fertilization.
   
Crop rotate with non-host to reduce corn residues and disease inoculum.
   

Apply fungicides such as  benomyl (e.g. Benlate®, Benophyl®) or maneb(e.g. Maneb®).

 
   

References

Stenocarpella macrospora and Stenocarpella maydis. Data Sheets on Quarantine Pests. EPPO quarantine pest.

The CIMMYT Maize Program. 2003. Maize Diseases: A Guide for Field Identification. 4th edition. Mexico, D.F.: International Maize and Wheat Improvement Center (CIMMYT).

To view other diseases,  click here.

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