In which of the following medium , callus should be placed to produce shoot ?

Options

A. Higher concentration of cytokinin ad lower concentration auxin
B. Lower concentration of cytokinin and higher a centration of auxin
C. Only cytokinin and no auxin
D. Only auxin and no cytokinin

Answer

To determine the appropriate medium for placing callus to produce shoots, we need to understand the role of plant hormones, specifically auxins and cytokinins, in plant tissue culture.

### Step-by-Step Solution:

1. **Understanding Callus**:
- Callus is a mass of undifferentiated cells that forms during tissue culture. It is essential for plant regeneration.

2. **Role of Hormones**:
- Two primary hormones involved in the differentiation of callus into shoots and roots are auxins and cytokinins.
- Auxins promote root formation, while cytokinins promote shoot formation.

3. **Hormonal Concentration**:
- If the concentration of auxins is higher than that of cytokinins, roots will develop from the callus.
- Conversely, if the concentration of cytokinins is higher than that of auxins, shoots will develop from the callus.

4. **Conclusion**:
- To produce shoots from callus, the medium should have a **higher concentration of cytokinins** and a **lower concentration of auxins**. This hormonal balance encourages the differentiation of callus into shoots.

5. **Correct Answer**:
- The correct medium for producing shoots from callus is one with **higher concentrations of cytokinins and lower concentrations of auxins**.