Lettuce: Aster yellows
categories: Lettuce Lettuce Diseases Vegetables
revision date: 2022-12-07 12:00
Biology
Aster yellows is caused by a phytoplasma which is a microorganism found in the phloem tissue of a plant. The phytoplasma is spread by leafhoppers and can also affect carrot, onion, potato, celery, and other crops, weeds, and ornamentals. Initial symptoms are seen on young leaves in the heart of the plant. These leaves turn yellow and may fail to develop normally, resulting in a thickened, stubby appearance. Affected leaves show characteristic pinkish or tan latex deposits on the underside of the midribs. Young plants may show yellowing of the outer leaves and severe stunting, while older plants may show only internal symptoms and the latex deposits.
Management Options
Use Integrated Pest Management (IPM) for successful plant problem management.
Non-chemical Management
Select non-chemical management options as your first choice!
- Control weeds in and around the garden.
- Control leafhoppers.
- Since leafhoppers tend to avoid shaded plants, shading lettuce may help reduce the risk of infection.
Chemical Management
IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.
- None recommended.