Maize lesion nematode

Systematic position: Pratylenchus zeae is a member of the order Tylenchida and the family Pratylenchidae. It is a migratory endoparasitic nematode recognized globally as a significant pathogen of various agronomic crops, specifically thriving in warm temperate and tropical soil environments.

Host crops: This nematode has an extensive host range. While it is primarily known for causing yield losses in maize (corn), it also parasitizes a variety of other crops including sorghum, sugarcane, rice, wheat, soybeans, and tobacco, making it a highly adaptable agricultural pest.

Biology and life cycle: The nematode completes its life cycle by invading roots and feeding on cortical cells. Both juvenile and adult stages are capable of moving within the root tissue and migrating through the soil to find new infection sites. The generation time is temperature-dependent, often requiring about a month to reach maturity under ideal soil warmth.

Nature of damage and pathogenicity: Infested plants exhibit symptoms of stunted growth, chlorosis, and reduced vigor. The feeding activity of Pratylenchus zeae causes distinctive necrotic lesions on the roots. These wounds inhibit water and nutrient uptake, often leading to reduced yield and increased susceptibility to secondary fungal root rot pathogens.

Protection measures: Integrated pest management (IPM) is essential for mitigating the impact of Pratylenchus zeae. Recommended strategies include:

• utilizing crop rotation with non-host or resistant plant species;
• application of nematicidal seed treatments;
• maintaining soil fertility to support root health;
• effective weed control to eliminate alternative host plants in the field.