Tomato mosaic virus
Caused by: Tomato mosaic virus (ToMV)Problem Category: Viral disease
Symptoms: Symptoms can occur at any growth stage and any part of the plant can be affected; infected leaves generally exhibit a dark green mottling or mosaic; some strains of the virus can cause yellow mottling on the leaves; young leaves may be stunted or distorted; severely infected leaves may have raised green areas; fruit yields are reduced in infected plants; green fruit may have yellow blotches or necrotic spots; dark necrotic streaks may appear on the stems, petioles leaves and fruit.
Comments: ToMV is a closely related strain of Tobacco mosaic virus (TMV), it enters fields via infected weeds, peppers or potato plants; the virus may also be transmitted to tomato fields by grasshoppers, small mammals and birds.
Management: Plant varieties that are resistant to the virus; heat treating seeds at 70°C (158°F) for 4 days or at 82–85°C (179.6–185°F) for 24 hours will help to eliminate any virus particles on the surface of the seeds; plant tomato on a 2-year rotation, avoiding susceptible crops such as peppers, eggplant, cucurbits and tobacco; disinfect all equipment when moving from infected areas of the field.
Control: grow resistant varieties to control the tomato mosaic virus