Cunninghamella

Cunninghamella is a genus of zygomycete fungi that acts as an opportunistic pathogen in various plant species. Known primarily for species such as Cunninghamella elegans, this fungus is widely distributed in soil and decaying organic matter. In an agricultural context, it poses a significant threat to stored produce, greenhouse seedlings, and wounded plant tissues, leading to rapid deterioration.

This pathogen specifically targets fruits, vegetables, and seeds, especially those already weakened by physiological stress or prior mechanical damage. Greenhouse crops are particularly vulnerable during early growth stages. Because the fungus thrives on high sugar content and moisture, it can cause severe economic losses if post-harvest storage conditions are not strictly managed.

The primary symptom is the development of a dense, fluffy white or greyish mycelium on the surface of the affected organs. Infected plant tissues become soft, watery, and eventually collapse due to the rapid enzymatic activity of the fungus. When seedlings are attacked, the stem base often darkens and undergoes necrosis, resulting in "damping-off" symptoms and the eventual death of the plant.

The spread of Cunninghamella is accelerated by high relative humidity (above 80%) and temperatures between 20°C and 28°C. Spores are easily disseminated via wind, water splashes during irrigation, and contaminated tools. In closed environments like greenhouses, poor ventilation and high planting density create the perfect breeding ground for the pathogen to establish and spread.

Integrated pest management (IPM) for this disease focuses on sanitation and environmental control. Key preventative actions include:

• Maintaining adequate spacing to ensure proper airflow.
• Disinfecting greenhouse surfaces and storage facilities.
• Using high-quality, fungicide-treated seeds.
• Removing and destroying all infected debris immediately to reduce inoculum pressure.