Which disease is wrongly matched ?

Options

A. White rust of crucifers-Cystopus candida
B. Ergot of rye-Claviceps purpurea
C. Damping opp-Pythium debaryanum
D. Late blight of potato-Alternaria solani

Answer

To solve the question "Which disease is wrongly matched?", we will analyze each option provided to identify the incorrect pairing of diseases and their causative agents.

### Step-by-Step Solution:

1. **Identify the First Option:**
- **Disease:** White rust of crucifer
- **Causative Agent:** Cystopus candida
- **Analysis:** This is a correctly matched pair. White rust is indeed caused by Cystopus candida.

2. **Identify the Second Option:**
- **Disease:** Ergot of rye
- **Causative Agent:** Claviceps purpurea
- **Analysis:** This is also a correctly matched pair. Ergot of rye is caused by Claviceps purpurea.

3. **Identify the Third Option:**
- **Disease:** Damping off
- **Causative Agent:** Pythium debaryanum
- **Analysis:** This is another correctly matched pair. Damping off is caused by Pythium debaryanum.

4. **Identify the Fourth Option:**
- **Disease:** Late blight of potato
- **Causative Agent:** Alternaria solani
- **Analysis:** This is the incorrectly matched pair. Late blight of potato is actually caused by Phytophthora infestans, not Alternaria solani.

5. **Conclusion:**
- The disease that is wrongly matched is **Late Blight of Potato** with **Alternaria solani**. The correct causative agent is **Phytophthora infestans**.

### Final Answer:
The disease that is wrongly matched is **Late Blight of Potato** (Option 4).

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