Previous Year Question
What are the advantages of fertigation in agriculture?
Controlling the alkalinity of irrigation water is possible.
Efficient application of Rock Phosphate and all other phosphatic fertilizers is possible.
Increased availability of nutrients to plants is possible.
Reduction in the leaching of chemical nutrients is possible.
Select the correct answer using the code given below:
1, 2 and 3 only
1, 2 and 4 only
1, 3 and 4 only
2, 3 and 4 only
Correct Answer: C
Detailed Solution
In fertigation, soluble fertilizers are delivered to the root zone of plants along with irrigation water. It is commonly used with a drip irrigation system.
Statement 1 is correct: In a fertigation system, the alkalinity and bicarbonate level of irrigation water can be controlled by using suitable acidic fertilizers or by injecting a controlled quantity of acid.
High alkalinity of water may cause elements such as calcium and magnesium to precipitate and clog drip emitters. Controlling alkalinity reduces this problem.
Statement 2 is incorrect: A fertilizer must be completely soluble in water to be used for fertigation.
Rock phosphate is very poorly soluble in water. Its particles may block drip pipes and emitters; therefore, it cannot be applied efficiently through fertigation.
All phosphatic fertilizers are also not suitable for fertigation. Only water-soluble phosphatic fertilizers that are chemically compatible with other fertilizers can be used.
Statement 3 is correct: Through fertigation, nutrients are supplied in small and frequent doses to the active root zone according to the growth stage of the crop.
This increases the availability of nutrients to plants and improves fertilizer-use efficiency.
Statement 4 is correct: Since nutrients are applied in controlled and split doses within the root zone, their probability of moving below the root zone is reduced.
This can reduce the leaching of mobile nutrients such as nitrate. Proper determination of irrigation and fertilizer quantities is necessary for this purpose.
Fertigation can save water and fertilizers, ensure uniform distribution of nutrients and reduce labour requirements.
Its success requires proper water quality, fertilizer solubility and compatibility, adequate filtration, regular flushing of the system and correct irrigation scheduling.