Which of the following diseases are a mismatch ?

Options

A. Bacteria : Black rot of crucifers and late blight of potato
B. Fungi : Brown rust of wheat and red rot of sugarcane
C. Virus: Tobacco mosaic and turnip mosaic
D. Both (A) and (B)

Answer

To solve the question regarding the mismatch of diseases and their causative agents, we will analyze each option step by step.

### Step 1: Identify the diseases and their causative agents
1. **Black rot of crucifers** - Caused by **Xanthomonas** (a bacterium).
2. **Late blight of potato** - Caused by **Phytophthora** (a fungus).
3. **Brown rust of wheat** - Caused by a **fungus**.
4. **Red rot of sugarcane** - Caused by a **fungus**.
5. **Tobacco Mosaic Virus** - Caused by a **virus**.
6. **Turnip Virus** - Caused by a **virus**.

### Step 2: Match each disease with its causative agent
- **Black rot of crucifers** - Correctly matched with **Xanthomonas**.
- **Late blight of potato** - Incorrectly matched; it should be matched with **Phytophthora** (fungus).
- **Brown rust of wheat** - Correctly matched with a **fungus**.
- **Red rot of sugarcane** - Correctly matched with a **fungus**.
- **Tobacco Mosaic Virus** - Correctly matched with a **virus**.
- **Turnip Virus** - Correctly matched with a **virus**.

### Step 3: Identify the mismatch
The only mismatch identified is:
- **Late blight of potato** is incorrectly matched as it is caused by **Phytophthora**, which is a fungus, not a bacterium.

### Conclusion
The mismatch disease is **Late blight of potato**.

### Final Answer
The disease that is a mismatch is **Late blight of potato**.

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