Corn Nematodes
Symptoms:
- Symptoms can look similar to nutrient deficiency, or insect or herbicide damage. Usually in parts of fields, not over the whole field.
- Symptoms and injury vary with type and numbers of nematodes involved.
- Wilting, stunting, small poorly-filled ears, nutrient deficiencies
- Short root systems with reduced number of fine feeder roots (dagger, stunt, and sting nematodes). Similar to grape colaspis injury.
- Short, stubby roots similar to dinitroaniline herbicide damage (needle, stubby root, and sting nematodes).
- Few fine roots and dark lesions on roots (lesion, dagger, lance, and spiral nematodes).
Nematodes Involved:
- Needle nematode (Longidorus sp.)
- Stubby root nematode (Trichodorus sp.)
- Sting nematode (Belonolaimus sp.)
- Dagger nematode (Xiphinema sp.)
- Stunt nematode (Tylenchorhynchus sp.)
- Sting nematode (Belonalaimus sp.)
- Lesion nemadotode (Pratylenchus sp.)
- Lance nematode (Hoplolaimus sp.)
- Spiral nematode (Helicotylenchus sp.)
Time of Occurence:
- Damage can occur in May and June.
- Damage will often not be visible until crop is under moisture or other stress after early summer.
Conditions Favoring Disease:
- Sandy soils
- Continuous corn on corn cropping
- Corn stressed by other factors.
Disease Management:
- Scout and sample moist soil and plants to determine if nematodes are a problem
- Rotate out of corn