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Extension > Garden > Diagnose a problem > What's wrong with my plant? > Vegetable > Lettuce and Endive > Discolored leaves

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Lettuce and Endive > Leaves > Discolored leaves

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  • Image: Fire Blight 1
  • Image: Fire Blight 2

Aster Yellows
Aster yellows phytoplasma

  • Plants infected when very young are overall yellow, stunted and may have deformed leaves
  • Plants infected when older; center leaves are pale yellow and stunted
  • Lettuce has a bitter taste
  • Drops of tan milky sap may be present at the midrib of the lower leaves
  • Symptoms are most severe in July and August
  • More information on Aster Yellows
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  • Image: Black Rot 1

Calcium deficiency

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  • Image: Fire Blight 1
  • Image: Eastern Tent Caterpillar 2
  • Image: Eastern Tent Caterpillar 3

White Mold
Sclerotinia sclerotiorum and Sclerotinia minor

  • Plant wilts and outer leaves drop to the ground
  • Base of the outer leaves are tan and water soaked
  • Rot progresses into the heart of the head
  • White cottony mold with small hard, black raisin like fungal structures can be seen at the base of the plant
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  • Image: Black Rot 1

Lettuce mosaic virus, Cucumber mosaic virus and others

  • Leaves have a random patches of yellow and green in a mosaic or mottled pattern
  • Leaves are misshapen, usually curled and deformed
  • Plants may be stunted
  • More information on Virus

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