Who first suggested presence of growth regulatory chemicals in plants ?

Options

A. Darwin
B. Went
C. Sachs
D. Paal

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks who first suggested the presence of growth regulatory chemicals in plants.

2. **Identifying the Scientist**: The scientist who first suggested this concept is Fritz W. Wendt.

3. **Historical Context**: In 1928, Fritz W. Wendt conducted experiments that led to the discovery of auxins, which are a class of plant hormones or growth regulators.

4. **Key Experiment**: Wendt isolated auxin from the tip of oat coleoptiles. He observed that the auxin diffused out from the tip into a gelatin block, demonstrating its role in plant growth regulation.

5. **Conclusion**: Therefore, the answer to the question is Fritz W. Wendt, who was pivotal in the early research on plant growth regulators.

**Final Answer**: Fritz W. Wendt

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