Harpophora root rot

Harpophora root rot is a fungal disease of maize caused by the pathogen Harpophora zeicola. This fungus primarily attacks the root system and the lower stalk of the plant, leading to significant physiological stress and hindering the transport of essential nutrients and moisture throughout the plant structure.

The disease mainly affects corn (maize) crops. The pathogen is classified as soil-borne, meaning it can survive in the soil for several growing seasons by colonizing infected crop residues, which allows it to persist even when the host plant is absent from the field for a short duration.

Symptoms of the infection include stunted plant growth, yellowing of the leaves, and wilting during periods of heat stress. Root inspection often reveals necrotic brown lesions, decay of the secondary root system, and softening of the crown tissue, which frequently results in lodging and lower ear development.

The development of Harpophora zeicola is heavily influenced by environmental conditions, particularly soil moisture levels and temperatures favoring fungal growth. The disease spreads through infested soil particles, contaminated crop debris, and movement of equipment, making field sanitation a critical management step.

Effective disease management relies on cultural practices and integrated pest management. Crop rotation is the most effective tool to break the disease cycle, alongside the use of fungicide-treated seeds and deep tillage practices to accelerate the decomposition of plant residues that harbor the fungus.

• Implementation of crop rotation.
• Use of fungicide-treated seeds.
• Deep tillage for residue management.
• Maintenance of soil health.
• Regular field monitoring for symptoms.