Necrosis in crops is due to the deficiency of

Options

A. Ca, K, Cu and Mg
B. N,K,S and Mo
C. N,S,Fe and Zn
D. Mg, S, Mn and Ca

Answer

To determine the cause of necrosis in crops due to nutrient deficiency, we will analyze the options provided and the role of each nutrient in plant health.

### Step-by-Step Solution:

1. **Understanding Necrosis**:
- Necrosis in plants refers to the death of plant cells or tissues, which can lead to visible symptoms such as browning or wilting of leaves and stems.

2. **Identifying Nutrient Deficiencies**:
- We need to evaluate the nutrients listed in each option and their known effects on plant health.

3. **Option Analysis**:
- **Option 1**: Calcium, Potassium, Copper, Magnesium
- Calcium deficiency can lead to cell wall instability and necrosis, especially in young tissues.
- Potassium deficiency often results in chlorosis followed by necrosis.
- Copper is involved in photosynthesis and can lead to necrosis if deficient.
- Magnesium is crucial for chlorophyll production; its deficiency can also cause necrosis.

- **Option 2**: Nitrogen, Potassium, Sulphur, Molybdenum
- Nitrogen deficiency typically leads to overall poor growth and chlorosis, but not directly necrosis.
- Potassium, as mentioned, can lead to necrosis.
- Sulphur is important for protein synthesis; its deficiency can cause some necrotic symptoms.
- Molybdenum is less commonly associated with necrosis.

- **Option 3**: Nitrogen, Sulphur, Iron, Zinc
- Nitrogen and Sulphur are less directly linked to necrosis.
- Iron deficiency leads to chlorosis but not typically necrosis.
- Zinc deficiency can cause stunted growth and some necrotic symptoms, but not as prominently.

- **Option 4**: Magnesium, Sulphur, Manganese, Calcium
- Magnesium and Calcium are both linked to necrosis.
- Sulphur and Manganese can contribute to various deficiencies but are less directly linked to necrosis.

4. **Conclusion**:
- After evaluating all options, the first option (Calcium, Potassium, Copper, Magnesium) is the most likely to cause necrosis due to the direct involvement of calcium, potassium, and magnesium in the health of plant tissues.

### Final Answer:
Necrosis in crops is due to the deficiency of **Calcium, Potassium, Copper, and Magnesium**.

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