Root-lesion nematodes

Systematic position: Root-lesion nematodes belong to the order Tylenchida and the family Pratylenchidae. They are migratory endoparasites that inhabit the cortical tissues of roots, causing significant disruption to the physiological processes of the host plant throughout the growing season.

Host range: These nematodes are widely recognized for their broad host range, known as polyphagous pests. They infest a vast variety of crops, including cereals, corn, potatoes, sugar beets, vegetables, and fruit trees. Their ability to survive in the roots of diverse weeds makes them difficult to eradicate from agricultural soil.

Biology and life cycle: The life cycle of Pratylenchus involves eggs, four juvenile stages, and adults. Both juveniles and adults are motile and capable of entering and leaving root tissues. Because they move through the soil and between roots, they can spread rapidly across a field, with generations completing in a few weeks under favorable conditions.

Nature of damage and pathogenicity: Damage is characterized by the formation of brown necrotic lesions on the roots. These wounds destroy root cells, reducing the plant's ability to uptake water and nutrients. Furthermore, these lesions serve as entry points for various soil-borne pathogens, leading to complex root rot diseases that severely diminish crop yield.

Control measures: Integrated pest management is essential for controlling Pratylenchus populations. Key strategies include:

• Crop rotation with non-host or trap crops.
• The use of certified nematode-free planting material.
• Effective weed management to eliminate host sources.
• Application of soil-applied nematicides when thresholds are exceeded.
• Soil solarization or steaming for intensive greenhouse systems.