UPSC Prelims 2016 · Question 49 of 98
UPSC Prelims 2016 question on Neem Coated Urea
- ExamUPSC CSE
- Year2016
- PaperGeneral Studies Paper I
- SubjectIndian Economy
- TopicAgriculture Economy
- DifficultyMedium
- TypeDirect
Why does the Government of India promote the use of ‘Neem-coated Urea’ in agriculture?
Show answer
Answer: B. Neem coating slows down the rate of dissolution of urea in the soil
Verdict
The answer is that neem coating slows down the rate of dissolution of urea in the soil.
Analysis
Only about thirty to forty per cent of the nitrogen in ordinary urea is taken up by crops. Applied urea converts to ammonium carbamate, part of which is lost as ammonia through volatilisation, and the remainder nitrifies to nitrates which leach away or are denitrified. Neem coating slows the conversion and dissolution, so nitrogen is released closer to the plant's uptake rate and less is lost. The nitrogen fixation option is wrong because fixation is a microbial process unrelated to urea coating, and the claim of no nitrous oxide at all is an absolute that cannot hold.
Source
Economic Survey 2015-16.
How to crack it
Reason from the loss pathway rather than from the additive. If a fertiliser's problem is that it dissolves and transforms faster than the crop can absorb it, the obvious fix is to slow the release, and any coating technology exists for exactly that. Then apply the absolutes test to the remaining options: not at all in the third option is a total denial and fails on a single exception. Mechanism plus quantifier closes the question twice over.