Citrus canker disease is caused by

Options

A. Virus
B. Fungus
C. Bacteria
D. Mycoplasm

Answer

**Step-by-Step Solution:**

1. **Identify the Disease**: The question asks about the causative agent of Citrus canker disease. Citrus canker is a well-known plant disease that affects citrus plants.

2. **Determine the Causative Agent**: According to the information provided, Citrus canker disease is caused by a specific bacterium.

3. **Name the Bacterium**: The bacterium responsible for Citrus canker is called *Xanthomonas axonopodis pv. citri*. This bacterium is classified as a gram-negative bacterium.

4. **Recognize Symptoms**: The symptoms of Citrus canker include the appearance of dark spots and lesions on the leaves and fruits of the citrus plants. Initially, these spots are small but can grow larger over time.

5. **Conclusion**: Based on the information gathered, the correct answer to the question is that Citrus canker disease is caused by bacteria.

**Final Answer**: Citrus canker disease is caused by *Xanthomonas axonopodis pv. citri*, which is a bacterium.

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