Bacterial Soft Rot
Beginner
Scientific Name
Erwinia carotovora subsp. carotovora
Identification
- Sunken water soaked lesions develop around damaged areas on the fruit or stem
- The water soaked areas expand rapidly
- Bacterial ooze may develop and secondary organisms may invade
- The fruit stem may discolour
- The entire fruit may fill with a watery soft slimy mass that is kept intact by the thin outer skin
Often Confused With
N/A
Period of Activity
Warm, moist weather is favourable for infection by the bacterial soft rot pathogens. Infection is generally associated with insect damage or other wounds.
Scouting Notes
Prevention of bacterial soft rot requires good control of fruit-feeding insects.
Thresholds
None established.
Advanced
Scientific Name
Erwinia carotovora subsp. carotovora
Identification
Sunken water soaked lesions develop around damaged areas on the fruit or stem. The water soaked areas expand rapidly. Bacterial ooze may develop and secondary organisms may invade. The fruit stem may discolour. The entire fruit may fill with a watery, soft, slimy mass that is kept intact by the thin outer skin.
Often Confused With
N/A
Biology
The pathogens cannot penetrate healthy fruit tissue, but the stem and cap are susceptible to attack. Infection can also occur through tissue injured by insects, sunscald, or other problems. If bacteria-laden water is able to enter the fruit, the pathogen can easily attack the inner fruit tissue. Infections can occur both in the field and post-harvest.
Period of Activity
Warm, moist weather is favourable for infection by the bacterial soft rot pathogens. Infection is generally associated with insect damage or other wounds.
Scouting Notes
Prevention of bacterial soft rot requires good control of fruit-feeding insects.
Thresholds
None established.
Management Notes
- Minimizing moisture on the fruit and controlling insect pests are important management factors.
- Excess nitrogen fertilization may promote soft rot.