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Tomato Diseases | Tomato Pith Necrosis Fact Sheets
Tomato Pith Necrosis
Identification
Plants:
- Yellowing of young leaves and leaflets
- Wilting of shoots on the upper portion of the plant (top wilting)
- Split or collapsed stems that are associated with dry brownish-gray lesions
- Stems are often hollow, black in color or have a ladder appearance when they are split open length wise
- Stems can appear swollen and contain large numbers of adventitious roots
Fruit:
- Greasy water-soaked blackened region on the blossom end of the fruit.
Favorable Environmental Conditions
- Cool night time temperatures (low to mid 60s °F)
- High relative humidity
- Prolonged periods of cloud cover
Often Confused With
- Bacterial Canker
- Bacterial Wilt (sub-tropical and tropical regions)
Scouting Notes
- The pathogen is most active when the plant is growing too rapidly due to excessive soil nitrogen levels.
- Foliar symptoms of pith necrosis are similar to early bacterial canker symptoms.
- Symptoms first develop when the first fruit cluster reaches the mature green stage.
- Fruit symptoms can be observed on the blossom end of the fruit but are rare.
- Plants should be monitored weekly for early symptoms and suspect plants should be sampled and submitted for plant disease diagnosis.