In tissue culture roots can be induced by :-

Options

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

Answer

**Step-by-Step Solution:**

1. **Understanding Tissue Culture**: Tissue culture is a technique used to grow plants in a controlled environment, where plant cells or tissues are cultured on a nutrient medium. This method allows for the regeneration of whole plants from small tissue samples.

2. **Role of Hormones in Tissue Culture**: In tissue culture, plant hormones (phytohormones) play a crucial role in the growth and differentiation of plant tissues. The two main types of hormones involved in root induction are auxins and cytokinins.

3. **Auxins**: Auxins are a class of plant hormones that promote root formation. They are essential for the development of roots in tissue culture. Higher concentrations of auxins are typically used to stimulate root growth.

4. **Cytokinins**: Cytokinins are another class of plant hormones that promote cell division and shoot formation. They are generally used in lower concentrations when the goal is to induce root formation, as high levels can lead to shoot development instead.

5. **Inducing Roots in Tissue Culture**: To induce roots in tissue culture, the ideal combination of hormones is crucial. The correct approach is to use a **higher concentration of auxins** and a **lower concentration of cytokinins**. This combination encourages root formation while suppressing shoot growth.

6. **Conclusion**: Therefore, the correct answer to the question "In tissue culture, roots can be induced by:" is **higher concentration of auxins and lower concentration of cytokinins**.

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