Here are tips on how to identify, control, and prevent mosaic viruses on a variety of plants.
What Are Mosaic Viruses?
Mosaic viruses affect more than 150 types of plants, including many fruits, vegetables, and flowers. The disease is characterized by leaves that are mottled with yellow, white, and light or dark green spots and streaks (in other words, a “mosaic” of these colors). Some of the most commonly infected plants include tomatoes, squashes, cauliflower, and cucumbers, but many more plants are susceptible.
Types of Mosaic Viruses
There are a number of mosaic viruses that commonly affect plants in the vegetable garden, including:
- Bean Common Mosaic Virus (BCMV) and Bean Yellow Mosaic Virus (BYMV) are the primary mosaic viruses that affect beans of all types. They are typically spread by aphids, but BCMV is also seed-borne, so do not save seeds from infected plants.
- Cucumber Mosaic Virus (CMV) is one of the most common types of mosaic viruses and tends to be spread by aphids. As can be inferred from its name, cucumber mosaic virus often affects cucumbers, but it is also a common problem for many other garden plants, including other cucurbits (melons, squashes), nightshades (tomatoes, peppers, eggplants, potatoes), and leafy greens (lettuce, spinach).
- Tobacco Mosaic Virus (TMV) spreads through seeds and direct contact, and the best way to avoid it is to grow resistant varieties.