Cunninghamella blakesleeana

Cunninghamella blakesleeana is a soil-borne fungus belonging to the order Mucorales. In agricultural systems, it acts primarily as a saprotroph or an opportunistic pathogen, infecting plant tissues that have already been compromised by abiotic stress or primary infection by other phytopathogens.

The host range of this fungus is broad, primarily affecting stored agricultural products, including various fruits, vegetables, and oilseeds like sunflower. It is particularly destructive to seeds and seedlings during germination, especially when planted in cold, wet, or poorly aerated soil conditions which delay initial plant growth.

The primary symptom of infection is the emergence of a fluffy, greyish-white mycelial mat on the surface of the plant material. This growth is accompanied by tissue degradation, softening, and the development of a characteristic decay that renders the affected produce unmarketable and unsuitable for consumption or industrial processing.

Environmental conditions are critical for the development of Cunninghamella blakesleeana. High humidity levels, exceeding 80%, combined with warm temperatures ranging from 20°C to 28°C, facilitate rapid mycelial spread and spore production. The airborne nature of the spores allows for efficient dispersal throughout warehouses, increasing the risk of cross-contamination.

Management and prevention strategies focus on limiting the environmental conditions favorable to the pathogen. Essential steps include rigorous post-harvest drying protocols to reduce moisture content below critical thresholds, maintaining optimal ventilation in storage facilities, and utilizing effective chemical seed treatments to protect germinating embryos from soil-borne infection.