Question

UPSC Prelims 2018 Question:

Consider the following:

Birds

Dust blowing

Rain

Wind blowing

Which of the above spread plant diseases?

1. 1 and 3 only
2. 3 and 4 only
3. 1, 2 and 4 only
4. 1, 2, 3 and 4

Answer (Detailed Solution Below)

Option 4: 1, 2, 3 and 4

Detailed Solution

Parasitic as well as viral diseases are transmissible, the parasites or issues being infectious to suitable host plants with ability to spread from host to host and from one area to another. The microscopic parasites or sub-microscopic infectious agents viz. viruses causing plant diseases are technically termed as ‘pathogens’.
- Direct transmission: The Pathogen is carried externally or internally on the seed or planting material like cuttings, sets, tubers, bulbs etc.
- Indirect transmission: The Pathogen carried independently by natural agencies like dust blowing, wind blowing, water including rain, animals, insects, mites, nematodes, birds etc.

Therefore, option (4) is the correct answer.

Subject: Science & Technology | Health and Diseases

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