Blue Discoloration

• Blue-eye is the common name for a fungal disease that infects corn when it is harvested and stored rather than when it is still on the plant. The condition is so named because its most recognizable symptom is a blue or bluish-green discoloration of the corn kernel.
  
  

Pathogens

• Many pathogenic fungi can cause blue-eye mold. Aspergillus glaucus is one species known to cause blue-eye, as are several Penicillium fungal species, especially Penicillium oxalicum.
  
  

Causes

• The presence of a fungus alone is typically not enough to cause a blue-eye infection. Experts consider improper storage of harvested corn kernels to be a major contributor to the disease. Corn kernels are dried before long-term storage, in part to prevent infection from a fungal pathogen. Any delays between harvest time and drying can leave corn kernels more susceptible to blue eye infection. Farmers also try to harvest corn at a specific moisture level to help prevent fungal infection. If the harvested corn has a higher-than-normal moisture content, infection by a blue-eye fungus is much more likely.
  
  

Blue-Eye Corn and Mycotoxicity

• Infected corn may contain mycotoxins, substances produced by some fungi that cause potentially serious health problems in humans. Not all blue-eye fungus species produce mycotoxins, so it is difficult to tell whether infected corn is unsafe. It is always best to err on the side of caution by never eating blue-eye-infected corn.