Callus can form shoot or root by changing ratio of

Options

A. Auxin to gibberllin
B. Auxin to cytokinin
C. Cytokinin to ethylene
D. Gibberellin to cytokinin

Answer

### Step-by-Step Solution:

1. **Understanding Callus Formation**: Callus is an undifferentiated mass of cells that can develop into various plant structures, including shoots and roots.

2. **Key Plant Hormones**: The formation of shoots or roots from callus is influenced by the ratio of specific plant hormones:
- **Auxins**: Promote cell elongation and root formation.
- **Cytokinins**: Promote cell division and shoot formation.

3. **Hormonal Ratio**: The ratio of auxins to cytokinins is crucial in determining whether the callus will develop into roots or shoots:
- **Higher Auxin to Cytokinin Ratio**: When auxin levels are higher than cytokinin levels, the callus will differentiate into roots.
- **Higher Cytokinin to Auxin Ratio**: When cytokinin levels are higher than auxin levels, the callus will differentiate into shoots.

4. **Conclusion**: Therefore, the correct answer to the question is that callus can form shoots or roots by changing the ratio of **Auxin to Cytokinin**.

### Final Answer:
Callus can form shoot or root by changing the ratio of **Auxin to Cytokinin**.

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