Root knot nematode life cycle and stages. Root knot nematodes spend most of their active life cycle in galls on roots. Second-stage juveniles invade new sites, usually near root tips, causing root cells to grow into giant cells where the nematodes feed. As feeding continues, the plant produces a gall around the infected area. Mature females produce eggs in a small gelatinous mass on the root surface (as shown) or inside the root.
Photo by Adapted from an illustration by Marvin Ehrlich.