Kluyveromyces yeast

The genus Kluyveromyces comprises a group of yeasts that function as opportunistic pathogens in post-harvest plant pathology. While these yeasts are widely employed in biotechnology and food science, their presence on fresh produce is classified as a significant cause of soft rot and quality degradation, leading to substantial losses in the agricultural supply chain.

The primary manifestation of the disease is yeast decay, a form of microbial spoilage. These yeasts colonize host tissues via surface wounds, bruising, or natural openings. Once inside, they utilize the plant's carbohydrates through fermentation, which breaks down cellular walls and leads to the rapid collapse of the tissue structure.

Susceptible crops include high-sugar produce such as grapes, strawberries, apples, peaches, and tomatoes. The high osmolarity and sugar content in these fruits provide an ideal growth medium, allowing the yeast to proliferate rapidly, especially in cases where the fruit's natural protective barriers are compromised during harvest or handling.

Symptomatology involves the formation of soft, water-soaked lesions on the fruit epidermis. These lesions are often characterized by a noticeable alcoholic or acidic odor, indicating active fermentation. In advanced stages, a white or cream-colored yeast biofilm may appear, and the fruit loses its firm texture, becoming pulpy and entirely unfit for market consumption.

Effective disease management relies on integrated post-harvest practices. Key strategies include:

• Maintaining strict temperature control to inhibit yeast metabolic activity.
• Implementing rigorous sanitation protocols for processing equipment and storage facilities.
• Minimizing physical injuries during harvest and transport.
• Managing orchard pests that create entry points for secondary infections.
• Utilizing humidity control to keep environments below the threshold for yeast growth.