Name the nematode which infects the roots of tobacco plants

Options

A. bacillus thuringiensis
B. cry Iac
C. meloidegyne incognita
D. none of these

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the name of the nematode that infects the roots of tobacco plants.

2. **Review the Options**: The options provided are:
- Bacillus thuringiensis
- Crylac
- Melodogyne incognita
- None of these

3. **Analyze Each Option**:
- **Bacillus thuringiensis**: This is a bacterium known for producing insecticidal proteins, not a nematode.
- **Crylac**: This is a gene, not a nematode.
- **Melodogyne incognita**: This is a known nematode that acts as a parasite to various plants, including tobacco.
- **None of these**: This option would only be correct if none of the other options were valid.

4. **Determine the Correct Answer**: Based on the analysis, Melodogyne incognita is the nematode that infects the roots of tobacco plants.

5. **Conclusion**: The correct answer to the question is **Melodogyne incognita**.

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