Yeast soft rot

Yeast soft rot is a post-harvest disease primarily caused by the yeast-like fungus Kluyveromyces marxianus. This pathogen utilizes a complex set of enzymes to degrade plant tissues, leading to the rapid liquefaction of the internal structures of bulb crops.

The disease mainly affects Allium species, specifically onions and garlic. Infection typically occurs due to pre-existing wounds or physiological weaknesses in the bulb, often originating in the field during the final stages of maturity when excessive moisture is present.

Symptoms are characterized by the softening of succulent scales, emitting a distinct, sharp, sour odor associated with fermentation. The tissue becomes water-soaked and loses its integrity, eventually collapsing into a mushy mass that can easily leak from the neck of the bulb.

Development and spread are accelerated by warm temperatures and poor ventilation within storage facilities. High humidity levels prevent the curing process from completing successfully, allowing the fungus to colonize neighboring healthy bulbs through physical contact or air circulation.

The economic impact of yeast soft rot is significant, as it leads to rapid inventory loss. Since the decay process progresses quickly, it can compromise entire batches of stored produce, making strict quality control and proper post-harvest handling essential for all growers.

• Prioritize harvesting under dry and favorable weather conditions.
• Implement proper curing procedures immediately after harvest.
• Regularly monitor storage facilities for temperature and humidity.
• Ensure adequate air circulation to prevent moisture buildup.
• Discard any bulbs showing signs of bruising or pre-existing rot.