UPSC Prelims 2020 Question:

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:

Explanation:

• • Fertigation is the process of dissolving fertilizer and distributing it with water in drip or spray irrigation system. Many researches have affirmed the superiority of fertigation over traditional fertilising techniques. 

• Advantages of fertigation are: 

• Improves efficiency of fertilizer use 
• Increases nutrient availability. So, point 3 is correct.
• Saves 20-40% fertilizer without affecting growth and yield 
• Saves labour and energy in application of fertilizer 
• Reduce environmental contamination through fertilizer run-offs 
• Reduces leaching of nutrients. So, point 4 is correct.
• Allows to alter the pH of the irrigation water. So, point 1 is correct.

• Disadvantages of fertigation are: 

• When the irrigation system fails, uneven nutrient distribution occurs. When crops are overwatered, it causes overfertilization or nutrient leaching.
• Chemical reactions between fertiliser and calcium, magnesium and/or  bicarbonates in water can cause chemical clogging.
• Suitable for fertilisers that are easily soluble or liquid. In a micro-irrigation system, phosphoric fertiliser and some micronutrients may precipitate. So, point 2 is not correct.
• It is necessary to use corrosion-resistant fertigation equipment.
• The possibility of chemical backflow into the water supply source.
  
  

Therefore, option (3) is the correct answer.

Subject: Geography | Agriculture and Allied Sectors