The amount of macronutrients per kg of dry matter is

Options

A. 10 mmole
B. Above 10 mmole
C. Less than 10 mmole
D. 0.1 mg

Answer

**Step-by-Step Solution:**

1. **Identify Macronutrients and Micronutrients:**
- Understand that there are 17 essential elements for plants, which are categorized into macronutrients and micronutrients.
- Macronutrients (9 in total) are required in larger quantities, while micronutrients (8 in total) are needed in smaller amounts.

2. **Determine the Amount of Macronutrients:**
- The question asks for the amount of macronutrients per kilogram of dry matter.
- It is established that the amount of macronutrients should be about 10 millimoles per kilogram of dry matter.

3. **Differentiate Between Macronutrients and Micronutrients:**
- Macronutrients include elements like potassium, magnesium, calcium, and sulfur, which are essential for plant growth and development.
- Micronutrients, on the other hand, are required in amounts less than 10 millimoles per kilogram.

4. **Evaluate the Options:**
- Option 1: Incorrect, as it suggests a lower amount than required for macronutrients.
- Option 2: Correct, as it states about 10 millimoles per kilogram, which aligns with the requirement for macronutrients.
- Option 3: Incorrect, as it suggests an amount less than 10 millimoles, which is characteristic of micronutrients.
- Option 4: Incorrect, as it also suggests an amount that does not meet the macronutrient requirement.

5. **Conclusion:**
- The correct answer to the question is Option 2: About 10 millimoles per kilogram of dry matter.

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