False root-knot nematode

Nacobbus dorsalis is a significant plant parasitic nematode classified within the order Tylenchida and the family Pratylenchidae. Known as the false root-knot nematode, it is highly destructive to a variety of essential food crops, causing physiological stress to the host plants by attacking their root systems.

The pest has a broad host range, including tomatoes, peppers, potatoes, sugar beets, and legumes. Due to its ability to survive in the soil as cysts or larvae for extended periods, it presents a persistent challenge in agricultural management and can easily spread through infected soil movement or contaminated planting material.

The life cycle involves four juvenile stages and the adult stage. The nematodes invade roots where they establish feeding sites, inducing the development of galls. Unlike true root-knot nematodes, these are capable of migrating both within the root tissue and back into the soil, which complicates diagnostic efforts and timing for effective treatment.

The primary symptom of infestation is the formation of galls on roots, which disrupts water and nutrient uptake. Infected plants exhibit stunted growth, chlorosis, and reduced yield. In severe cases, the root system decays, leading to the total loss of the plant, especially under conditions of additional environmental stress.

Management strategies focus on integrated pest management (IPM) practices, such as rigorous crop rotation, the use of certified nematode-free seedlings, and soil solarization or chemical fumigation in high-infestation areas. Monitoring soil health and implementing strict quarantine measures are essential to preventing the further spread of Nacobbus dorsalis in unaffected fields.