Lettuce & Endive > Leaves > Discolored leaves
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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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- Leaves turn yellow and eventually wilt
- More information on Calcium deficiency...
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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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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...