Potato rot nematodes are microscopic worms approximately 1.4 millimeters long. Their life cycle takes place inside potato tubers where they eat starch grains. This causes the affected tissues to become brown and powdery, and the surface of the tuber becomes covered with dark patches with dry cracking skin. The nematodes live inside the living tissue where they aggregate rapidly as the fecund females each produce up to 250 eggs. They survive in stored tubers during the winter and can infect the stolons of planting material. After infection, the nematodes move throughout the plant tissue producing a pectinase enzyme, which causes cell degeneration and is the main causal agent of the rot observed. The soil plays only a secondary role in the transfer of this nematode.