Hormone that has negative effect on apical dominance is

Options

A. cytokinin
B. gibberellin
C. auxin
D. Both (b) and ( c )

Answer

To answer the question regarding which hormone has a negative effect on apical dominance, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Apical Dominance**: Apical dominance refers to the phenomenon where the main central stem of the plant grows more strongly than the other side stems. This is primarily regulated by plant hormones.

2. **Identifying Key Hormones**: The main hormones involved in apical dominance are auxins, cytokinins, and gibberellins. Auxins are known to promote apical dominance, while cytokinins promote lateral bud growth.

3. **Analyzing Cytokinins**: Cytokinins are hormones that promote cell division and can stimulate the growth of lateral buds. When cytokinins are present, they can counteract the effects of auxins, leading to the growth of lateral shoots.

4. **Evaluating Other Hormones**:
- **Auxins**: These hormones are responsible for promoting apical dominance. Therefore, they do not have a negative effect on apical dominance.
- **Gibberellins**: These hormones can promote growth but do not specifically counteract apical dominance.
- **Lateral Bud Growth**: Hormones that promote lateral bud growth, like cytokinins, negatively affect apical dominance.

5. **Conclusion**: Based on the analysis, the hormone that has a negative effect on apical dominance is **cytokinins**.

### Final Answer:
The hormone that has a negative effect on apical dominance is **cytokinins**.

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