Tobacco mosaic virus

Definition

Tobacco mosaic virus (TMV) is a rod-shaped virus that infects a variety of plants, particularly tobacco, causing characteristic mottling and discoloration of leaves. This virus is significant in understanding viral evolution and classification due to its simple structure and ability to replicate efficiently within host cells, providing insights into how viruses adapt and interact with their hosts.

5 Must Know Facts For Your Next Test

1. TMV was the first virus to be discovered, identified by Martinus Beijerinck in 1898, which set the stage for virology as a scientific field.
2. This virus is known for its characteristic filamentous shape and consists of a single strand of RNA surrounded by a protective protein coat.
3. TMV primarily affects tobacco plants but can also infect other plants in the Solanaceae family, such as tomatoes and peppers.
4. The infection process begins when TMV enters the plant through mechanical injury or insect vectors, leading to symptoms like leaf curling and stunted growth.
5. Research on TMV has been crucial for understanding viral behavior, including mechanisms of infection and replication, making it a model organism in virology studies.

Review Questions

• How does the structure of tobacco mosaic virus contribute to its ability to infect host plants?
  • The rod-shaped structure of tobacco mosaic virus allows it to efficiently penetrate plant cell walls and enter host cells. This shape also facilitates the virus's ability to move within the plant tissues once inside. The viral RNA is encased in a protein coat that helps protect it from degradation while enabling interaction with host cellular machinery for replication.
• Discuss the ecological and agricultural impacts of tobacco mosaic virus infections in crop production.
  • Tobacco mosaic virus can significantly affect crop production by reducing the yield and quality of infected plants, particularly in tobacco and related species. Infected crops may exhibit symptoms such as leaf discoloration and distortion, leading to economic losses for farmers. Moreover, because TMV can be transmitted through mechanical means and insect vectors, controlling its spread is essential for maintaining healthy crops and preventing widespread outbreaks.
• Evaluate the implications of studying tobacco mosaic virus for understanding viral evolution and host interactions in broader ecological contexts.
  • Studying tobacco mosaic virus provides valuable insights into viral evolution and how viruses adapt to their hosts over time. Its relatively simple genetic structure allows researchers to investigate mechanisms of mutation and adaptation, offering lessons on how viruses might evolve resistance to host defenses. Additionally, understanding TMV's interactions with various plant hosts helps inform agricultural practices and disease management strategies, potentially guiding efforts to combat other viral infections in both agricultural and natural ecosystems.

Related terms

RNA Virus: A type of virus that has ribonucleic acid (RNA) as its genetic material, which can be single-stranded or double-stranded.

Plant Virus: A virus that specifically infects plants, often causing diseases that can lead to significant agricultural losses.

Viral Replication: The process by which a virus makes copies of itself within a host cell, often utilizing the host's cellular machinery.