Pratylenchus species
The lesion Nematode

  • Damage to Corn.   Damage from Pratylenchus can range from severe to very slight, depending on the degree of infestation, and environmental conditions. 
  • Biology.   There are at least 5 Pratylenchus species that cause root lesions in corn.  Pratylenchus are small nematodes (0.30 - 0.75 mm) that invade the corn roots to feed and lay their eggs.
  • Ecology.   Although Pratylenchus does best in sandy soils, this nematode is widespread and can reach high population levels in the finer soils of the mid-western U.S. corn belt.
  • Symptoms.  Lesion nematodes can cause severe pruning of the roots, resulting in stunting, as well as reduction in stalk diameter, stalk and root weights. Cholorosis or other discoloration is often evident, also.
  • Damage to other crops. 
  • Control.   Rotation with cotton and peanuts has been found to reduce populations of lesion nematodes in Georgia. Chemical  nematicides have also been successful in reducing their numbers.
One or more of these nematode species currently is or could potentially be an APHIS quarantine pest.