Question

Late blight of potato is caused by:

• A. Fungus
• B. Bacterium
• C. Virus
• D. Mealybug

Hint:

Late blight of potato:
- Caused by Phytophthora infestans (oomycete).
- Historical significance: Irish Potato Famine.
- Management: Fungicides, resistant varieties.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
This question tests knowledge of plant diseases and their causal organisms.

Step 2: Detailed Explanation:
Late blight of potato is caused by the fungus-like oomycete Phytophthora infestans.
It is a devastating disease that caused the Irish Potato Famine (1845-1852).
Symptoms: Water-soaked lesions on leaves, stems, and tubers.
Bacterium (B): Not the cause of late blight.
Virus (C): Not the cause of late blight.
Mealybug (D): An insect pest, not a pathogen.
Thus, late blight is caused by a fungus (oomycete).

Step 3: Final Answer:
Thus, late blight of potato is caused by a fungus, which corresponds to option (A).
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