Zygomycosis

Zygomycosis refers to plant infections caused by fungi belonging to the class Zygomycetes, particularly the order Mucorales. These fungi typically function as opportunistic pathogens that thrive on decaying matter but can aggressively colonize weakened or damaged plant tissues, leading to severe post-harvest losses.

These pathogens affect a diverse range of crops, including fleshy fruits, vegetables like tomatoes and sweet potatoes, and stored grains. They are particularly destructive to produce that has sustained mechanical injuries, such as cuts or bruises, providing the fungi with an easy entry point to begin colonization.

The primary symptom of infection is the rapid development of soft rot. Infected areas become mushy and are quickly covered by a coarse, whisker-like mycelial growth, which progresses from white to a dark gray or black color as the sporangia develop. The affected produce often gives off a fermented or sour odor due to the rapid enzymatic decomposition.

Environmental conditions are the main drivers for the spread of zygomycosis. Warm temperatures coupled with high humidity levels (often above 85%) provide the perfect trigger for spore germination. Poor ventilation in storage warehouses significantly increases the risk of the fungus spreading from a single infected fruit to the entire batch.

Effective management focuses on physical barriers and sanitation rather than chemical intervention. Preventing physical damage during harvesting is the most critical step. Additionally, maintaining cool storage temperatures, ensuring optimal airflow to prevent moisture condensation, and strictly removing diseased materials are essential practices to mitigate losses.