Who prescribed a medium containing microelements for the first time?

Options

A. Gericke
B. Arnon Hoagland
C. Knop
D. Stout

Answer

**Step-by-Step Solution:**

1. **Understanding Microelements**: Microelements, also known as micronutrients or trace elements, are essential nutrients that plants require in very small amounts. They play crucial roles in various physiological processes within the plant.

2. **Identifying the Micronutrients**: The primary micronutrients essential for plant growth include Boron, Zinc, Manganese, Iron, Copper, Molybdenum, and Chlorine. These elements collectively constitute less than 1% of the dry weight of most plants.

3. **Historical Context**: The question asks for the individual who first prescribed a medium containing these microelements. This indicates a historical contribution to the field of plant nutrition.

4. **Finding the Answer**: The first person to prescribe a medium that included microelements was Arnon Hoagland. This was a significant development in understanding plant nutrition and the importance of micronutrients.

5. **Final Answer**: Therefore, the answer to the question is that Arnon Hoagland prescribed a medium containing microelements for the first time.

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