Cool soil temperatures and episodes of rainfall are contributing to the development of seedling diseases in corn this spring. The most common seedling diseases that have been identified in samples submitted to the UNL Plant and Pest Diagnostic Clinic are those caused by Pythium and, less frequently, Fusarium species.

Seedling diseases can be caused by any of several common soil-borne organisms, such as Pythium, Fusarium, Rhizoctonia or plant parasitic nematodes. Seedling diseases are often difficult to diagnose because they have similar symptoms. Diagnosis of a specific disease may be of limited value because management may be similar for several seedling diseases. Microscopic examination and other laboratory analyses of the diseased seedlings often can identify the cause(s) of the problems.

Seedling diseases can be confused with insect injury, herbicide damage, planting problems, or environmental stresses that often have similar symptoms. Possible symptoms of seedling diseases include:

  • Rotted seed prior to germination
  • Rotted or discolored seedlings after germination prior to emergence
  • Postemergence seedling damping off
  • Root decay