The essential element present in plant tissues in amount of more than 10m mole `kg^(-1)` of dry matter is :

Options

A. B
B. Mo
C. CI
D. Mg

Answer

To solve the question regarding the essential element present in plant tissues in an amount of more than 10 moles per kg of dry matter, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Classification of Nutrients**:
- Nutrients are classified into macronutrients and micronutrients based on the quantity required by plants.
- Macronutrients are required in larger amounts (more than 10 moles per kg of dry matter), while micronutrients are required in smaller amounts (less than 10 moles per kg of dry matter).

2. **Identify Macronutrients**:
- Common macronutrients include Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), and Sulfur (S).
- These elements are essential for various physiological functions in plants and are present in significant quantities.

3. **Identify Micronutrients**:
- Micronutrients include Iron (Fe), Copper (Cu), Manganese (Mn), Molybdenum (Mo), Zinc (Zn), Boron (B), Chlorine (Cl), and Nickel (Ni).
- These are required in smaller amounts compared to macronutrients.

4. **Analyze the Given Options**:
- The question provides options including Boron, Molybdenum, Chlorine, and Magnesium.
- Boron, Molybdenum, and Chlorine are all classified as micronutrients, which means they are present in amounts less than 10 moles per kg of dry matter.

5. **Determine the Correct Answer**:
- Among the options, Magnesium is the only element classified as a macronutrient, which is required in amounts greater than 10 moles per kg of dry matter.
- Therefore, the essential element present in plant tissues in an amount of more than 10 moles per kg of dry matter is **Magnesium**.

### Final Answer:
The essential element present in plant tissues in an amount of more than 10 moles per kg of dry matter is **Magnesium**.

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