What are the advantages of fertigation in agriculture ? 1. Controlling the alkalinity of irrigation water is possible. 2. Efficient application of Rock Phosphate and all other phosphatic fertilizers is possible. 3. Increased availability of nutrients to plants is possible. 4. Reduction in the leaching of chemical nutrients is possible. Select the correct answer using the code given below :
- (a) 1, 2 and 3 only
- (b) 1, 2 and 4 only
- (c) 1, 3 and 4 only ✓ UPSC's answer
- (d) 2, 3 and 4 only
Why the answer is (c)
• Fertigation delivers water-soluble fertilisers through drip or sprinkler irrigation directly to the root zone.
• Acids injected into the system can neutralise alkaline irrigation water and prevent emitter clogging (statement 1).
• Nutrients supplied in small, frequent doses are more readily available to plants (statement 3), and precise placement cuts leaching losses below the root zone (statement 4).
• Statement 2 is wrong: rock phosphate and most phosphatic fertilisers are insoluble or react to clog lines; only special soluble forms (e.g. MAP, phosphoric acid) suit fertigation.
• Hence 1, 3 and 4 only, option (c).
Why the other options are wrong
- (a) 1, 2 and 3 only
- Statement 2 is wrong: rock phosphate is unsuitable for fertigation.
- (b) 1, 2 and 4 only
- Statement 2 is wrong; statement 3 is correct.
- (d) 2, 3 and 4 only
- Statement 2 is wrong; statement 1 is correct.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2020, held on 4 October 2020. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.