Question

Write about the Tobacco Mosaic Disease.

Answer 1

Tobacco mosaic disease:

Tobacco mosaic disease is a wide range of infections caused by the Tobacco mosaic virus (TMV).

Tobacco mosaic virus (TMV):

1. It is a single-stranded RNA virus species from the genus Tobamovirus.
2. It infects a broad range of plants, especially tobacco and other species of the family Solanaceae.
3. The infection leads to noticeable patterns, such as mosaic like mottling and decolourisation of leaves.
4. TMV was the first virus to be discovered.
5. Although it was known later in the 19th century that a non-bacterial contagious disease was causing damage to tobacco crops.
6. It was in 1930 that the infectious agent was identified to be a virus.
7. This virus was crystallised by W.M. Stanley.

Symptoms of tobacco mosaic disease:

1. The initial symptom of this viral disease is the formation of a light green colour between the veins of juvenile leaves.
2. This is followed by quick development of a "mosaic" which is a mottled pattern of light and dark green areas in the leaves.
3. Rugosity may also be observed, in which the infected plant leaves show small wrinkles.
4. These symptoms develop very fast and are more visible on younger leaves.
5. Its infection does not cause the death of the plant, but if infection occurs in the early season, the plant growth gets stunted.