Plant-parasitic nematodes can cause serious damage to corn. There are numerous species that occur in Iowa, including the dagger, lance, lesion, needle, stubby-root, and stunt nematodes. Symptoms of nematode damage on corn include stunting and/or yellowing of foliage and stunting, swelling, and/or browning of roots. In the past few weeks, the Iowa State University Plant Disease Clinic has received samples from fields in southeastern Iowa with corn damaged by the needle nematode.
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