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 which of the following diseases are a mismatch, we will analyze each option provided in the question step by step.

### Step 1: Analyze the First Option
- **Diseases Mentioned**: Black root of cruciferous plants and late blight of potatoes.
- **Causes**:
- Black root of cruciferous plants is caused by a bacterium known as **Xanthomonas campestris**.
- Late blight of potatoes is caused by a fungus known as **Phytophthora infestans**.

**Conclusion**: The first option is a mismatch because it incorrectly associates late blight of potatoes (fungal disease) with bacteria.

### Step 2: Analyze the Second Option
- **Diseases Mentioned**: Brown rust of wheat and red rot of sugarcane.
- **Causes**:
- Brown rust of wheat is caused by a fungus called **Puccinia triticina**.
- Red rot of sugarcane is caused by a fungus known as **Colletotrichum falcatum**.

**Conclusion**: This option is correct as both diseases are caused by fungi.

### Step 3: Analyze the Third Option
- **Diseases Mentioned**: Tobacco virus and turnip mosaic virus.
- **Causes**:
- Tobacco virus is caused by the Tobacco mosaic virus (TMV).
- Turnip mosaic virus is caused by the Turnip vein clearing virus.

**Conclusion**: This option is also correct as both diseases are caused by viruses.

### Final Conclusion
After analyzing all the options, we find that the first option (black root of cruciferous and late blight of potatoes) is the mismatch.

### Answer:
The mismatch disease is the first option: Black root of cruciferous plants (bacteria) and late blight of potatoes (fungus).

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