Clavispora

Clavispora is a genus of ascomycetous yeasts that includes several species known for their role as plant pathogens, most notably Clavispora lusitaniae (the sexual state of Candida lusitaniae). This pathogen is widely recognized in agronomy as an agent responsible for opportunistic infections, primarily causing fruit and vegetable decay during the pre-harvest and post-harvest stages.

The fungus affects a variety of economically important crops, including pome and stone fruits, grapes, and various vegetable species. It typically colonizes tissues with high sugar content, exploiting mechanical injuries or physiological cracks in the epidermis to invade the plant structure, which leads to rapid deterioration of the affected produce.

Symptoms of Clavispora infection are characterized by soft, water-soaked lesions that expand rapidly across the surface of the fruit. As the infection progresses, the tissues lose their structural integrity and turn mushy. Under high humidity, a distinctive white or creamy-colored mass of yeast-like growth often appears on the lesion, releasing spores that can contaminate surrounding healthy fruits.

Development and spread of the disease are highly dependent on environmental conditions, particularly high relative humidity and temperatures ranging from 20°C to 28°C. Rain and wind facilitate the dispersal of spores from debris to healthy plant organs. In orchards and vineyards, insect damage serves as the primary gateway for the fungus to establish itself and initiate colonization.

Effective management and prevention of Clavispora require a multi-faceted approach to reduce the inoculum load and protect the yield:

• Strict sanitation protocols in orchards and post-harvest storage facilities.
• Integrated pest management (IPM) to reduce insect-related fruit wounding.
• Application of targeted fungicides during the fruit maturation period.
• Careful handling during harvest to prevent mechanical damage, followed by prompt cooling of the produce.