Science · X-Factor Notes
The Fertilizers revision notes for UPPCS Prelims.
21 revision facts
| Concept | What to remember | Asked in UPPCS |
|---|---|---|
| Fertilizer Definition | Material (natural or synthetic) applied to soils or plant tissues to supply one or more essential plant nutrients. | - |
| Need for Fertilizers | Necessary because continuous cropping depletes soil nutrients. | - |
| Manure vs. Synthetic Fertilizer | Manure (organic material like animal feces/urine) is a natural fertilizer. Synthetic fertilizer is an inorganic salt manufactured in factories. Manure provides humus to the soil, which synthetic fertilizer does not. Synthetic fertilizers contain N, P, K in abundance compared to manure. | - |
| Phosphorus Necessity | Chemical fertilizers are necessary for the phosphorus need of plants, as one metric ton of organic manure supplies barely 2 or 3 kg of phosphorus. | U.P. Lower Sub. (Pre) 1998 |
| Categories of Synthetic Fertilizers | Classified based on nutrients provided: Nitrogeneous, Phosphatic, and Potassium fertilizers. | - |
| Mixed Fertilizer | NPK is an example of a mixed fertilizer, supplying Nitrogen, Phosphorus, and Potassium. | I.A.S. (Pre) 1995 |
| Humus | Humus (dark organic material from decay) is an example of Organic colloids. | U.P.R.O./A.R.O. (Pre) 2014 |
| Concept | What to remember | Asked in UPPCS |
|---|---|---|
| Nitrogen Absorption Forms | Plants absorb nitrogen primarily as nitrate ion (NO3-) or ammonium ion (NH4+). | - |
| Urea Composition | Urea is an amide group fertilizer, containing 46–47% nitrogen (N). The elements present are C, H, N, O. | UPPCS (Spl.) (Mains) 2008 |
| Urea Solubility | Urea is relatively more soluble in water at $20^\circ \text{C}$ compared to Ammonium Sulphate, DAP, or Ammonium Chloride. | U.P. P.C.S. (Mains) 2017 |
| Urea Manufacturing | For industrial purposes, urea is produced from synthetic ammonia and carbon dioxide. | Uttarakhand P.C.S. (Mains) 2006 |
| Nitrogen Quantity in Urea | Approximately 2.2 kg of urea is required to supply 1 kg of nitrogen. | U.P. B.E.O. (Pre) 2019 |
| Foliar Application | Urea is the most popular fertilizer for foliar application (applying nutrients directly to leaves) due to its high solubility and effective absorption. | U.P. Lower Sub. (Pre) 2015; UPPCS (Mains) 2015 |
| Wheat Cultivation Fertilizer | Nitrogen is the fertilizer used for wheat cultivation. | UPPCS (Mains) 2007 |
| DAP Composition | Diammonium Phosphate (DAP) contains 18% N and 46% P2O5. | UPPCS (Mains) 2008 |
| Concept | What to remember | Asked in UPPCS |
|---|---|---|
| Maximum Acidity in Soil | Ammonium Sulphate is the fertilizer that leaves the maximum acidity in the soil. | UPPCS (Pre) 1996 |
| Excessive Use of N-Fertilizers | Excessive use of nitrogenous fertilizers can lead to an increase in the acidity of soil and leaching of nitrate to the groundwater. | I.A.S. (Pre) 2015 |
| Neem-coated Urea | The Government promotes Neem-coated Urea because the coating slows down the rate of dissolution of urea in the soil, preventing rapid nitrification and ensuring plants gain more nutrients. | I.A.S. (Pre) 2016 |
| Green Manuring | The practice involves growing leguminous plants and incorporating them into the soil. Sunhemp is the most suitable crop for green manuring. | UPPCS (Mains) 2015 |
| Synthetic Fertilizer Policy | The MRP of urea is statutorily fixed by the Government of India. | I.A.S. (Pre) 2020 |
| Ammonia Production | Ammonia, used to produce nitrogenous fertilizers like urea, is manufactured by the Haber process, where hydrogen is often obtained from natural gas (methane) via thermal processes. | I.A.S. (Pre) 2020 |