Which part of the tabacco plant is infected by meloidogyne incognita?

Options

A. Leaf
B. Stem
C. Root
D. Flower

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which part of the tobacco plant is infected by the nematode Meloidogyne incognita.

2. **Identifying Meloidogyne incognita**: Meloidogyne incognita is a genus and species of nematode, which is known to cause diseases in plants, particularly tumor formation.

3. **Analyzing the Options**: The options provided are:
- a) Leaf
- b) Stem
- c) Root
- d) Flower

4. **Evaluating Each Option**:
- **Leaf**: The leaf is not affected by Meloidogyne incognita. This nematode does not cause diseases in the leaf; instead, it is associated with other diseases like tobacco mosaic disease.
- **Stem**: The stem is also not the primary site of infection for Meloidogyne incognita. The stem does not provide the necessary environment for the nematode to thrive or form nodules.
- **Root**: The root is the correct answer. Meloidogyne incognita infects the roots of the tobacco plant, leading to the formation of galls or nodules where the nematodes can survive and reproduce.
- **Flower**: The flower is not affected by this nematode. The nematode's life cycle and effects are localized to the roots.

5. **Conclusion**: Based on the analysis, the part of the tobacco plant that is infected by Meloidogyne incognita is the **root**.

**Final Answer**: The root of the tobacco plant is infected by Meloidogyne incognita.

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