Fusarium dry rot

The causal agent of Fusarium dry rot is the fungus Gibberella pulicaris (anamorph Fusarium sambucinum). This pathogen is a significant soil-borne fungus capable of surviving in organic matter and soil for extended periods, serving as a constant threat to agricultural production.

The primary crop affected by this pathogen is the potato. The disease is primarily a storage issue, where the fungus enters the tubers through wounds, cuts, or bruises caused during harvesting, handling, or washing operations.

Symptoms of the infection typically appear as dark, slightly depressed lesions on the surface of the tuber. As the disease progresses, the internal tissues become dry and shriveled, leading to the formation of internal cavities. These voids are often filled with fluffy fungal mycelium, which can vary in color from white to pink or light yellow, while the outer skin eventually collapses into characteristic concentric rings.

Development and spread are favored by high humidity levels and storage temperatures between +10 °C and +25 °C. Poor ventilation in warehouses accelerates the movement of spores between tubers, allowing the rot to spread rapidly through the pile and potentially destroying a large percentage of the stored crop if left unchecked.

Effective management requires an integrated approach. Farmers should prioritize careful harvesting to minimize mechanical damage and ensure tubers are properly cured before storage. Maintaining low storage temperatures, ensuring proper airflow, and utilizing authorized chemical treatments on seed potatoes are crucial steps in preventing significant economic losses from this persistent disease.