Nematode may refer to:
- Potato cyst nematode (Globodera rostochiensis and Globodera pallida) - Cause yellow or brown spheres or cysts on the outside of Solanaceae roots.
- Potato rot nematode (Ditylenchus destructor) - damages carrots and potato tubers during storage, especially under abnormal conditions of storage.
- Root-knot nematode (Meloidogyne spp.) - exist in soil in areas with hot climates or short winters and cause a swelling of the roots from within resulting in galls.
- Stem and bulb nematode (Ditylenchus dipsaci) - is a plant pathogenic nematode which cause bulbs and stems of alliums to become distorted and swollen.