Necrosis mainly occurs by the deficlency of

Options

A. Ca, Mg
B. N, S
C. Mn, Mo
D. Fe, Mn

Explanation

### Step-by-Step Solution:

1. **Understanding Necrosis**:
- Necrosis refers to the death of tissue in plants. It is a significant symptom that indicates a deficiency of essential nutrients.

2. **Identifying Deficiency Symptoms**:
- In plants, deficiency symptoms can manifest in various forms such as:
- Chlorosis (yellowing of leaves)
- Stunted growth
- Inhibition of cell division
- Premature leaf fall
- Necrosis is one of these symptoms, indicating that the plant is not receiving adequate nutrients.

3. **Minerals Associated with Necrosis**:
- Necrosis is primarily associated with deficiencies in certain minerals. The key minerals that can lead to necrosis include:
- Calcium
- Magnesium
- Copper
- Potassium

4. **Conclusion**:
- Among the minerals listed, Calcium and Magnesium are particularly known to cause necrosis when they are deficient in the plant. Therefore, necrosis mainly occurs due to the deficiency of these minerals.

### Final Answer:
Necrosis mainly occurs due to the deficiency of Calcium and Magnesium.

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