In Tobacco callus, which one shall induce shoot differentiation in combination of auxin and cytokinin

Options

A. Higher concentration of cytokinin and lower concentration of auxin
B. Lower concentration of cytokin and higher concentration of auxin
C. only cytokinin and no auxin
D. Only auxin and no cytokinin.

Answer

To solve the question regarding the induction of shoot differentiation in tobacco callus using auxin and cytokinin, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Tobacco Callus**:
- Tobacco callus is an undifferentiated mass of plant cells. It is crucial to understand that callus cells can differentiate into various structures, including roots and shoots.

2. **Role of Plant Hormones**:
- Two key plant hormones are involved in the differentiation of plant tissues: auxin and cytokinin.
- Auxin is primarily involved in root formation, while cytokinin promotes shoot formation.

3. **Hormone Concentration Effects**:
- The concentration of auxin and cytokinin determines the type of differentiation:
- **Higher Auxin and Lower Cytokinin**: This combination promotes root differentiation.
- **Higher Cytokinin and Lower Auxin**: This combination promotes shoot differentiation.
- **Equal Concentrations of Auxin and Cytokinin**: This leads to the maintenance of the callus state (undifferentiated).

4. **Analyzing the Options**:
- The question asks for the combination that induces shoot differentiation.
- Therefore, we need to identify the option that indicates a higher concentration of cytokinin and a lower concentration of auxin.

5. **Conclusion**:
- The correct answer is the option that specifies a higher concentration of cytokinin and a lower concentration of auxin, as this combination is responsible for inducing shoot differentiation in tobacco callus.

### Final Answer:
The combination that induces shoot differentiation in tobacco callus is **higher concentration of cytokinin and lower concentration of auxin**.

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