TMV was discovered by-

Options

A. Mayer
B. Ivanowsky
C. Towrt
D. Pasteur

Answer

To answer the question "TMV was discovered by-", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding TMV**: TMV stands for Tobacco Mosaic Virus, which is a virus that infects plants, particularly tobacco and other members of the Solanaceae family.

2. **Identifying the Scientists**: The question provides four options: Mayor, Ivanovsk, Part, and Pasteur. We need to evaluate each option to find out who discovered TMV.

3. **Evaluating Each Option**:
- **Mayor**: The transcript mentions that Mayor does not relate to the discovery of TMV, as he focused on a different concept.
- **Ivanovsk**: The transcript states that Ivanovsk was the first scientist to discover the virus, specifically the TMV. He referred to the virus as a "poisonous fluid" in Latin.
- **Part**: The transcript does not provide any information about Part in relation to TMV.
- **Pasteur**: While Pasteur made significant contributions to microbiology, particularly with bacteria, he is not associated with the discovery of TMV.

4. **Conclusion**: Based on the evaluation, the scientist who discovered TMV is Ivanovsk.

### Final Answer:
TMV was discovered by **Ivanovsk**.

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