Cause Tomato mosaic virus or Tobacco mosaic virus, which also affects pepper, eggplant, petunia, and many other plants. Poor sanitation and handling infected plants are the primary means of spread.
Symptoms Symptoms depend on the virus strain. Often, foliage mottles with alternating yellowish and dark green areas. New leaflets curl and are slightly malformed. More severely affected leaves are badly distorted and rather fern-like. Plants usually are somewhat stunted and bear few fruit if infected when young. Plants and fruit are not much smaller if plants are infected after they reach fruiting stage. Sometimes necrotic spots or streaks develop on stems and leaves.
- Use resistant varieties.
- Do not use tobacco products while handling plants. Wash hands thoroughly with soap and water after smoking and before touching plants.
- Early in the season, remove and destroy all affected plants, fallen leaves and other debris from infected plants. Roguing later in the season is not effective.
- Use only sterilized pots, flats, and planting media.
- Do not handle healthy plants after touching infected plants.