Intermodal elongation in sugarcane stem is promoted by

Options

A. Gibberellin
B. Cytokinin
C. Auxin
D. ABA

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks about the substance that promotes intermodal elongation in the sugarcane stem. Intermodal elongation refers to the growth of the stem between the nodes, which is crucial for the overall height and yield of the plant.

2. **Identifying the Options:**
The options provided are:
- Gibberellin
- Cytokinin
- Arginine
- ABA (Abscisic Acid)

3. **Analyzing Each Option:**
- **Gibberellin:** Known to promote stem elongation and is a growth hormone in plants. It is particularly effective in increasing the length of internodes in various plants, including sugarcane.
- **Cytokinin:** Primarily involved in cell division and growth, but does not specifically promote elongation of internodes.
- **Arginine:** An amino acid that is not directly involved in promoting plant growth or elongation.
- **ABA (Abscisic Acid):** Generally acts as a growth inhibitor and is involved in stress responses, not promoting elongation.

4. **Conclusion:**
Based on the analysis, gibberellin is the correct answer as it is specifically known for promoting intermodal elongation in sugarcane stems.

5. **Final Answer:**
Intermodal elongation in sugarcane stem is promoted by **Gibberellin**.

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