Question

On an average well-rotted FYM contains ------- \(K_2O\) (percent)

• A. 0.75
• B. 1.00
• C. 0.50
• D. 0.20

Hint:

Remember the classic N-P-K rule of thumb for standard FYM:
\[ \mathbf{0.5 - 0.2 - 0.5} \]
This represents the respective percentages of \(\text{N}\), \(\text{P}_2\text{O}_5\), and \(\text{K}_2\text{O}\).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Farm Yard Manure (FYM) is a valuable bulky organic manure prepared from decomposed cow dung, urine, litter, and fodder residues.
Understanding the average NPK (Nitrogen, Phosphorus, and Potassium) nutrient composition of FYM is essential for planning balanced fertilizer applications.

Step 2: Detailed Explanation:
Let us review the average nutrient content of well-rotted Farm Yard Manure (FYM):
- Nitrogen (\(\text{N}\)): It contains approximately \(0.5\%\) nitrogen.
- Phosphorus (\(\text{P}_2\text{O}_5\)): It contains approximately \(0.2\%\) phosphorus.
- Potassium (\(\text{K}_2\text{O}\)): It contains approximately \(0.5\%\) potassium.
Thus, the average primary nutrient composition of FYM is represented as:
\[ \text{N : P}_2\text{O}_5\text{ : K}_2\text{O} = 0.5\% \text{ : } 0.2\% \text{ : } 0.5\% \]
Based on this standard composition, the potassium (\(\text{K}_2\text{O}\)) content in well-rotted FYM is \(0.50\%\).

Step 3: Final Answer:
On average, well-rotted Farm Yard Manure contains 0.50% potassium (\(K_2O\)).