Post Harvest Diseases:: Vegetables:: Tomato
Bacterial Soft Rot and Hollow Stem :Erwinia carotovora pv. carotovora |
Symptom:
- Fruit -soft watery decay of fruit, starting at one or more points, as very small spots.
- Enlarge-very rapidly until the entire fruit -soft watery mass.
- Pathogen liquefies fruit tissue by breaking down the pectate "glue" that holds plant cells together
- leakage-internal collapse resembling a shriveled water balloon.
Identification of pathogen:
Bacteria:
- gram-ve, rod with rounded ends
- Motile with 1 to 6 peritrichous flagella
- Single-celled - rapidly multiply and spread-in water.
Favourable condition:
- During wet weather and High humidity,
- Heavy rain fall or irrigation
- Warm temperatures in the (20–30 °C)
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Oozed liquid |
Infected tomato |
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Spread and survival:
- Wounds
- The connective tissue at the stem end - an entry point for the bacteria present in the sepals of young tomato fruit
- They can be spread by rainstorms, insects, harvest crews, picking containers, and packinghouse equipment.
- Soft rot bacteria can even pass from one fiberboard shipping carton to an adjacent carton when the cartons become soaked with the rotten material of decayed fruit.
- These bacteria readily disperse from rotten fruit by direct contact or movement of juices or water
Management:
- Remove infected plant debris an destroy
- Seed treatment- carbendazim 2g/kg
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Content validator:
Dr. M. Deivamani, Assistant Professor, Horticulture Research Station, Yercaud-636602.
Source of Images:
http://erec.ifas.ufl.edu/tomato-scouting-guide/diseases/erwinia-soft-rot.shtml
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