Nematodes That Effect Plants

Soil Nematodes

• According to Cornell University's online plant clinic, one group of nematodes that affects plants is composed of roundworms that spend their whole life in the soil and roots of plants. Master Gardener's website refers to these type of roundworms as endoparasitic nematodes. Some common endoparasitic nematodes are the root knot nematode, the stunt nematode and the lance nematode. These nematodes cause symptoms of infestations in plants such as wilting, yellowing, loss of foliage and stunted growth.

Foliage Nematodes

• One type of nematode spends part of its time feeding on plant foliage. Master Gardener refers to this group as ectoparasitic nematodes. Most of the ectoparasitic nematodes belong to the genera Aphelenchus or Aphelenchoides.These roundworms cause angled lesions on leaf plants. Some leaves turn completely brown and die. Though nematodes normally do not kill plants, they weaken them and leave them susceptible to other infections.

Pine Wood Nematode

• Cornell University identifies a nematode that does not fit into the two primary categories (endoparasitic and ectoparasitic) of roundworms. The Pine Wood nematode is unique in that it attacks mainly Japanese Black Pine trees. This roundworm is also different in the way it attacks the host. It fills up the sieve tubes that make up the pine's vascular system, thus rendering the system ineffective or weak.