Tobacco mosaic virus

Definition

Tobacco mosaic virus (TMV) is a rod-shaped plant virus that infects a wide range of plant species, particularly tobacco and other members of the Solanaceae family. It was the first virus to be discovered and characterized, making it a foundational element in the history of virology and significantly contributing to our understanding of viral structure and behavior.

5 Must Know Facts For Your Next Test

1. TMV was first isolated in 1892 by Dmitri Ivanovsky and later characterized by Wendell Stanley in 1935, marking important milestones in virology.
2. The virus has a helical structure, with its genome consisting of single-stranded RNA encapsulated within a protein coat.
3. TMV infects over 150 different species, demonstrating a wide host range, which complicates control strategies in agriculture.
4. Symptoms of TMV infection can include mottled leaves, stunted growth, and reduced crop yields, impacting both ornamental and agricultural plants.
5. Control methods for TMV include resistant plant varieties, crop rotation, and rigorous sanitation practices to prevent transmission.

Review Questions

• How did the discovery of tobacco mosaic virus contribute to the development of modern virology?
  • The discovery of tobacco mosaic virus laid the groundwork for modern virology as it was the first virus to be isolated and characterized. This breakthrough allowed scientists to understand the nature of viruses, leading to advances in viral classification, structure analysis, and replication mechanisms. TMV's study helped establish essential techniques that are still used today in the research and management of viral diseases.
• Discuss the structural features of tobacco mosaic virus and how they relate to its function and infection process.
  • Tobacco mosaic virus has a helical structure with a single-stranded RNA genome surrounded by a protective protein coat. This arrangement not only provides stability but also facilitates the entry of the virus into host cells. When TMV infects a plant, it hijacks the host's cellular machinery to replicate its RNA and produce more viral proteins, leading to widespread infection within the plant.
• Evaluate the economic impact of tobacco mosaic virus on agriculture and the strategies used for its control.
  • Tobacco mosaic virus poses significant economic challenges due to its ability to infect numerous crop species, leading to reduced yields and increased management costs for farmers. The economic impact is felt particularly in tobacco production but extends to other crops as well. Control strategies include developing resistant plant varieties, implementing crop rotation practices, and maintaining strict hygiene measures in agricultural settings. These approaches aim to minimize the spread of TMV and protect crop productivity.

Related terms

Plant Virus: A type of virus that primarily infects plants, causing a variety of diseases and symptoms that can affect crop yield and health.

Virion: The complete, infective form of a virus outside a host cell, consisting of genetic material encased in a protein coat.

Symptomatology: The study of symptoms associated with viral infections in plants, which can include discoloration, stunted growth, and wilting.