Beginner

Scientific Name
Pectobacterium carotovorum, Dickeya chrysanthemi

Identification

• Sunken water soaked lesions develop around damaged areas on the fruit
• The water soaked areas expand rapidly
• Bacterial ooze may develop and secondary organisms may invade
• The entire fruit may deteriorate to 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.

Scouting Notes
Wet conditions and insect damage, mechanical damage or hail could make soft-rot infection more likely.

Thresholds
None established.

Advanced

Scientific Name
Pectobacterium carotovorum, Dickeya chrysanthemi

Identification
Sunken water soaked lesions develop around damaged areas on the fruit. The water soaked areas expand rapidly. Bacterial ooze may develop and secondary organisms may invade. The entire fruit may deteriorate to a watery soft slimy mass that is kept intact by the thin outer skin.

Often Confused With
N/A

Biology
Bacterial soft rot causes serious losses in the field, in transit and in storage. Insect damage, mechanical damage or hail will predispose plants to soft-rot infection. Soft rot spreads rapidly in warm, humid conditions. It is spread by direct contact, hands, tools, soil water, insects and splashing rain or irrigation.

The soft rot bacteria overwinter in infected tissues, in the soil, and on contaminated equipment and containers. It can also overwinter in certain insects.

Period of Activity
Warm, moist weather is favourable for infection by the bacterial soft rot pathogens.

Scouting Notes
Wet conditions and insect damage, mechanical damage or hail could make soft-rot infection more likely.

Thresholds
None established.

Management Notes
Plant into well-drained soils and maximize air flow through the plant canopy. Once the disease is identified in a field, avoid overhead irrigation. Rotate with less-susceptible crops (cereals or corn) and control chewing insects.

Post-harvest infections may occur if water used during post-harvest operations is not treated to kill pathogens, especially if the fruit imbibe the water. In dump-tanks, maintain water temperature at 5°C above fruit temperature and do not immerse fruit for more than three minutes to reduce the risk of water entering the fruit. Dry stem scars are more resistant to water imbibation post-harvest.  Fruit harvested in wet conditions have a higher risk of post-harvest infection.