Three mosaic viruses infect beans: bean common mosaic, bean yellow mosaic, and cucumber mosaic. Symptoms may include yellow or green mosaic or mottle patterns of infected leaves, vein banding, and interveinal yellowing. Leaves may also be distorted, cupped or curled downward, or wrinkled.
This group of diseases is spread from plant to plant by aphids and leafhoppers. It is not practical to try to control virus diseases by using insecticides to control insects. Reflective mulches may reduce or delay infections as it helps repel insects from plants. Pull up plants showing symptoms; they will be unproductive and may allow disease to spread to nearby healthy plants. Keep broadleaf weeds down, because they may serve as a reservoir of viruses and facilitate spread to beans. Resistant varieties may be available.
Mosaic pattern of bean yellow mosaic virus
Downward curling of common mosaic virus