Root lesion nematodes are a group of plant-parasitic nematodes belonging to the genus Pratylenchus. They are among the most economically important nematodes in agriculture because they damage roots and reduce crop yields.
They cause root rot and growth reduction and can worsen diseases like Verticillium wilt and Rhizoctonia scab. Damaged roots also make plants more vulnerable to other pathogens. These nematodes are common in sandy and light soils, often occurring in mixed populations.
Root lesion nematodes enter roots and migrate through tissues, killing cells and leaving brown lesions. The cells the nematodes pass through are sucked dry and die. This can be seen on the outside by brown spots (lesions).
The nematodes remain mobile throughout their lives, moving to new roots as old ones die. Eggs are laid in soil or roots, hatching in 9–25 days depending on temperature. P. penetrans lays 1–2 eggs daily for about five weeks. With a short life cycle, they produce 2–3 generations per year.