UPSC Prelims 2009 Q67: Science & Technology – Biology
Consider the following statements:
1. Sweet orange plant is propagated by grafting technique.
2. Jasmine plant is propagated by layering technique.
Which of the statements given above is/are correct?
- (a) 1 only
- (b) 2 only
- (c) Both 1 and 2
- (d) Neither 1 nor 2
Answer: (c) Both 1 and 2
Explanation
Checking two plant propagation claims
Different plants use different vegetative propagation techniques, matched here to specific species.
| Statement | Verdict | Reason |
|---|---|---|
| 1. Sweet orange propagated by grafting | Correct | Sweet orange (citrus) is commonly propagated through grafting, ensuring desirable fruit traits |
| 2. Jasmine propagated by layering | Correct | Jasmine is commonly propagated through layering, a simple vegetative method |
Plant propagation facts:
| Plant | Technique |
|---|---|
| Sweet orange | Grafting |
| Jasmine | Layering |
Answer: (c) Both 1 and 2.
Why each option is right or wrong
- (a) Incorrect. Statement 2 (jasmine-layering) is also correct, so '1 only' is incomplete.
- (b) Incorrect. Statement 1 (sweet orange-grafting) is also correct, so '2 only' is incomplete.
- (c) CORRECT. Both sweet orange's grafting propagation and jasmine's layering propagation are accurate.
- (d) Incorrect. Since both statements are accurate, 'neither' is wrong.
Key point
Sweet orange is propagated by grafting, AND jasmine is propagated by layering — both plant-propagation-technique pairings are accurate.
Remember
Sweet orange: propagated by grafting. Jasmine: propagated by layering.
Common mistakes
- Confusing grafting (used for citrus like sweet orange) with layering (used for plants like jasmine).
- Assuming all plants use the same vegetative propagation method.
- Not knowing the specific technique-plant pairings tested here.
Exam tip
Sweet orange = grafting. Jasmine = layering. Different plants, different vegetative propagation techniques.
Sources
- NCERT Class XII Biology — Reproduction in Organisms (vegetative propagation)
- Indian Council of Agricultural Research — Handbook of Horticulture