Question

Among the following, which is not a source for passive dispersal of plant pathogen.

• A. Water
• B. Air
• C. Soil
• D. Insect

Hint:

Water, air and insects carry inoculum to new hosts; soil is the medium in which soil-borne pathogens persist (NTA key: Soil).

Answer 1

The Correct Option is C

Step 1: Understanding the Question:

• The question asks which of the listed agents is NOT a source for passive dispersal of a plant pathogen.

Step 2: Detailed Explanation:

• Passive dispersal means the pathogen is carried from one place to another by an external agency (water splash and irrigation water, wind-borne air currents, insects and other vectors, etc.).

• As per the NTA final answer key, the option marked as the answer is (C) Soil.

• Water, air and insects are the commonly cited agencies that carry inoculum to new plants, whereas soil is the medium in which soil-borne pathogens persist, and is therefore treated as the odd one out by the examining body.

Step 3: Final Answer:
The correct option is (C) Soil, as per the NTA final answer key.