Premature leaf fall is due to deficiency of

Options

A. sodium
B. potassium
C. zinc
D. phosphorus.

Explanation

To determine the cause of premature leaf fall in plants, we can analyze the options provided:

1. **Sodium**: Sodium is not considered an essential element for plants. While it can be beneficial in small amounts, it does not play a significant role in preventing premature leaf fall.

2. **Potassium**: A deficiency in potassium can lead to symptoms such as chlorosis (yellowing of leaves) and necrosis (death of tissue). However, it is not specifically linked to premature leaf fall.

3. **Zinc**: Zinc deficiency primarily causes chlorosis in plants. While it affects plant health, it is not directly associated with premature leaf fall.

4. **Phosphorus**: Phosphorus deficiency is known to cause several issues in plants, including premature leaf fall, necrosis, and chlorosis. This makes phosphorus a strong candidate for the cause of premature leaf fall.

After evaluating all the options, we conclude that the deficiency responsible for premature leaf fall is **Phosphorus**.

**Final Answer**: Premature leaf fall is due to deficiency of **Phosphorus**.

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