Late blight and Early blight diseases of potato are caused by :

Options

A. Same fungus at different times
B. Two different fungus belonging to same group
C. Two different fungus belonging to different group
D. Same fungus at same time

Answer

To answer the question regarding the causative agents of late blight and early blight diseases of potato, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Diseases**: Recognize that late blight and early blight are two distinct diseases that affect potatoes.

2. **Research Early Blight**: Understand that early blight is primarily caused by two closely related fungi, specifically:
- **Alternaria tomatophylla**
- **Alternaria solani**
These fungi are known to thrive in soil and plant debris.

3. **Classify Early Blight Fungi**: Note that both Alternaria species belong to the class **Deuteromycetes** (imperfect fungi), which are characterized by the absence of a sexual reproductive phase.

4. **Research Late Blight**: Identify that late blight is caused by a different fungus:
- **Phytophthora infestans**
This fungus prefers moist and cold environments.

5. **Classify Late Blight Fungus**: Recognize that Phytophthora belongs to the class **Oomycetes**, which is a different group from Deuteromycetes.

6. **Compare the Causative Agents**: Conclude that late blight and early blight are caused by different fungi, which belong to different taxonomic groups (Deuteromycetes for early blight and Oomycetes for late blight).

7. **Select the Correct Option**: Based on the analysis, the correct answer to the question is that late blight and early blight are caused by two different fungi belonging to different groups.

### Final Answer:
Late blight and early blight diseases of potato are caused by two different fungi belonging to different groups.

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