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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Vegetable > Tomato > Soft and rotted fruit

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Tomato > Fruit > Soft and rotted fruit

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  • Image: Anthracnose 1
  • Image: Anthracnose 2
  • Image: Anthracnose 3

Colletotrichum coccodes

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  • Image: Blossom End Rot 1
  • Image: Blossom End Rot 2
  • Image: Blossom End Rot 3

Blossom End Rot

  • Affects only fruit
  • The bottom of the tomato turns tan and soft, then black, sunken, and rotten
  • Fruit may look short or stumpy, not fully expanded due to rot
  • Common when water levels vary from irrigation or drought followed by rain
  • More information on Blossom End Rot
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  • Image: Alternaria Fruit Rot 1
  • Image: Alternaria Fruit Rot 2
  • Image: Alternaria Fruit Rot 3

Alternaria Fruit Rot
Alternaria alternata

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  • Image: Late Blight 1
  • Image: Late Blight 2

Late Blight
Phytophthora infestans

  • Irregular water-soaked lesions on leaves, turn olive then brown
  • Leaves, stems and petioles turn brown and shrivel
  • Fruit spot is round olive colored, can cover whole fruit
  • Infected tissue is covered with white mycelia is wet weather
  • Disease spreads very rapidly in cool wet weather
  • More information on managing plant diseases in the home garden
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  • Image: Cold injury 1
  • Image: Cold injury 2

Cold injury

  • Leaves look water-soaked and soft, then turn black
  • Fruit becomes soft water-soaked and rots
  • Leaves show injury immediately, fruit may not show symptoms for 5 to 7 days
  • Occurs at temperatures below 50° F
  • Follow these tips on growing healthy vegetables
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  • Image: White Mold 1
  • Image: White Mold 2
  • Image: White Mold 3

White Mold
Sclerotinia sclerotiorum

  • Dark, firm watersoaked lesion on stem
  • Girdled stems die and turn bone white
  • Inside dead stems are black mouse poop shaped sclerotia
  • Fruit are soft and rotted
  • Cottony white mycelia inside and outside infected stems when humidity is high
  • Favored by cool humid conditions
  • More information on managing diseases in the home vegetable garden

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