Question 97 from UPSC CSE 2018 - General science and Science & Technology

Question

Consider the following:
1. Birds
2. Dust blowing
3. Rain
4. Wind blowing
Which of the above spread plant diseases?

IASCODEX · Accepted Answer

Correct Option: D. 1, 2, 3, and 4

Strategy: - Assess birds, dust, rain, and wind for their ability to actively or passively carry pathogens.
- The assessment confirms birds can carry spores/microbes, and dust serves as a vehicle for fungal/bacterial spores.
- Rain aids in splashing and disseminating pathogens, while wind is a classic vector for airborne disease.
- As all four contribute to plant disease spread, all associated statements are correct.

Key Info: Plant diseases primarily spread through various agents that transport pathogenic organisms (such as fungi, bacteria, viruses, nematodes). Major dispersal methods include:

- Birds: Certain birds may carry infectious spores or bacteria on their bodies, beaks, or feet from one plant to another, sometimes following feeding or perching activities.
- Dust blowing: Dust often contains fungal spores and bacteria, especially in agricultural fields or during dry weather, facilitating long-distance spread when lifted by the wind.
- Rain: Rain splashes can move fungal spores and bacteria from infected to healthy plants, particularly in crops with dense canopies. Rainwater runoff may also carry pathogens to new soil locations.
- Wind blowing: Wind is a critical dispersal medium for many plant pathogens, especially those producing lightweight spores, such as rusts, mildews, and certain viruses. Airborne spread can occur over considerable distances and is a major concern for large-scale infestations.

Supplementary details:
- Other dispersal agents include insects, nematodes, humans (via tools and clothing), water irrigation, and animals.
- Common plant diseases with wind or rain dispersal include wheat rust (Puccinia spp.), powdery mildew, and bacterial blights.
- Management of plant diseases often requires understanding and interrupting these multiple transmission mechanisms.

IASCODEX · Answer

Option A: 1 and 3 only

IASCODEX · Answer

Option B: 3 and 4 only

IASCODEX · Answer

Option C: 1, 2, and 4 only

Consider the following: Birds Dust blowing Rain Wind blowing Which of the above spread plant diseases?

Consider the following:

Birds

Dust blowing

Rain

Wind blowing
Which of the above spread plant diseases?