Tobacco mosaic virus (TMV), once a serious disease of burley, rarely occurs in fields now since many varieties have excellent resistance. The most notable symptom of this disease is the mosaic of dark and light green areas on foliage. TMV is easily transmitted from plant to plant by mechanical means (e.g., worker's hands, cultivation, etc.). (Photo: Kenneth Seebold)

In addition to mosaic symptoms, vein-banding (darker green tissue following along veins) may occur. Foliage tips may appear distorted or puckered. (Photo: Kenneth Seebold, UK)

Necrosis (browning) associated with TMV infections is referred to as "mosaic burn." (Photo: Kenneth Seebold, UK)