Helicotylenchus species
The Spiral Nematodes

  • Damage to Corn.  Helicotylenchus pseudorobustus  is a common and well-known parasite of corn, especially in the mid-western U.S.  Crop losses are hard to measure because this nematode often occurs with other species of parasitic nematodes.
  • Biology.   At least three species of spiral nematodes are known as parasites of corn.  These nematodes have a characteristic arcuate to spiral body shape when at rest.
  • Ecology.  Spiral nematodes are seemingly ubiquitous with corn, and can occur in large numbers in a wide variety of soils.
  • Symptoms.   Mild stunting and reduced yields occur where populations are large.  Small light to dark brown lesions may also occur on infected plants.
  • Damage to other crops. 
  • Control.   Chemical control may be of value when spiral numbers are high and other species are contributing to root damage.