Cause Alfalfa mosaic virus (AMV), which is transmitted by aphids and can be seedborne. This virus has a broad host range (attributed to multiple species of aphid vectors) and infects at least 430 species of 51 dicot plant families including alfalfa (some varieties are asymptomatic), beans, clover, pea, potato, and tomato. Cilantro plantings were found infected with AMV in western Oregon during 2017. Subsequent testing of samples of seed planted in affected cilantro fields showed AMV to be present in seed samples.
Symptoms Symptoms range from a mild-yellow and green mottle to a bright-yellow mottle. There can also be dwarfing and leaf distortion. Infected plants are predisposed to drought injury.
Cultural control
- Plant seed that has been certified to be AMV-free by official seed testing.
- Scout plantings for disease.
- Avoid growing cilantro near alfalfa fields.