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