Decay in storage can be a wet rot caused by soft rot bacteria or Pythium, a common fungal-like organism. Soft rot often follows frost damage or mechanical damage. Pythium is most common where soil moisture is excessive and temperatures are high.
Dry rot is most commonly caused by a soil-inhabiting fungus called Fusarium.
Avoid bruising tubers during harvest or handling to aid control of both soft rot bacteria and Fusarium. Discard badly damaged or rotted tubers before storage. Store tubers in a dark location at high humidity and at 60 to 70 degrees F for seven to 10 days. After this period, they should be stored at 35 to 45 degrees F under humidities greater than 70 percent.
