Paratrichodorus

Paratrichodorus is a genus of migratory ectoparasitic nematodes within the Trichodoridae family (order Triplonchida). Often referred to as stubby root nematodes, these microscopic pests are widely recognized in agronomy for their ability to significantly damage root systems and transmit persistent plant viruses.

These nematodes primarily infest agricultural crops such as potatoes, onions, carrots, and various horticultural plants. They thrive in porous, sandy, and light-textured soils, which facilitate their rapid movement towards the growing root tips where they feed and reproduce.

The life cycle consists of an egg stage, four larval molts, and the adult stage. Unlike endoparasitic nematodes, Paratrichodorus remain outside the root tissue. Using their curved stylets, they penetrate cell walls to feed on the cytoplasm, causing immediate physiological disruption and potential necrosis of the root epidermal cells.

The primary economic damage results from the "stubby root" symptom, where root elongation is halted, leading to a stunted, bushy root system. More severely, they act as vectors for viruses such as the Tobacco Rattle Virus (TRV). This viral transmission leads to internal necrosis, commonly known as spraing in potatoes, which renders crops unmarketable.

Managing Paratrichodorus requires an integrated pest management (IPM) strategy. Essential steps include implementing long-term crop rotation, maintaining strict weed control, and testing soil before planting sensitive crops. In intensive systems, the use of soil fumigants or specific nematicides may be necessary to reduce population levels in highly infested fields.

• Root system stunting
• Vector for Tobacco Rattle Virus (TRV)
• Yield loss in sandy soil environments
• Reduction in nutrient uptake