TMV infection causes symptoms that start with light yellow-green and dark green mosaic symptoms. The disease can also cause fruit symptoms including mosaic pattern and internal browning.

TMV is a seed-borne virus and may be transmitted mechanically by sap and human actions. It may also present in tobacco products and can be spread by people who use them in production.

Leaflet distortions can sometimes be noticed and is generally referred as “leaf strapping”, “shoe-string”, or “fern leaf”. Cucumber Mosaic Virus (CMV) can also cause similar symptoms.

Severe leaf yellow with the veins in green is characteristic at advanced symptom. Nutrient deficiencies and other plant diseases can also cause similar symptoms.

Mixed infection of TMV and CMV may cause distortion of leaves, short internodes and mild to severe mosaic patterns. The plants may also show stunting for TMV by itself or in mixed infection.

Here we decided to have some fun with staining for confirmation of TMV. Epidermal strips of a tobacco leaf infected with TMV stained in azure A (blue stain) showing X-bodies (X) and nuclei (N)

Epidermal strips of a tobacco leaf infected with TMV stained in azure A (blue stain) showing hexagonal crystalline aggregate plates (C) and nuclei (N)

Epidermal strips of a tobacco leaf infected with TMV stained in calcomite orange/ brilliant green showing X-bodies (X) and nuclei (N).

Epidermal strips of a tobacco leaf infected with TMV stained in calcomite orange/ brilliant green showing showing crystalline aggregate plates (C) and nuclei (N).