Method of raising new plants in large number from a small plant tissue over a culture medium is

Options

A. Callus formation
B. Micropropagation/tissue culture
C. Micrografting
D. Juvenility

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for a method of raising new plants in large numbers from a small plant tissue over a culture medium.

2. **Identifying the Options**: The options provided are:
- A. Thallus formation
- B. Micropropagation / Tissue culture
- C. Micrografting
- D. Juvenility

3. **Analyzing Each Option**:
- **A. Thallus formation**: This refers to the growth of a thallus, which is a simple plant body that is not differentiated into stem and leaves. This is not a method for raising new plants from tissue.
- **B. Micropropagation / Tissue culture**: This is a technique where small pieces of plant tissue (explant) are cultured in a nutrient medium to grow into new plants. This method allows for the rapid production of a large number of plants.
- **C. Micrografting**: This involves joining two plant parts together, but it does not involve raising new plants from tissue culture.
- **D. Juvenility**: This term refers to the early developmental stage of a plant and is not related to the propagation method.

4. **Selecting the Correct Answer**: Based on the analysis, the correct method for raising new plants in large numbers from small plant tissue over a culture medium is **B. Micropropagation / Tissue culture**.

5. **Explanation of Micropropagation**:
- In micropropagation, a small part of the plant (explant) such as a leaf, stem, or root is selected.
- The explant is sterilized to prevent contamination.
- It is then placed in a nutrient-rich culture medium where it can grow and develop roots and shoots.
- After sufficient growth, the new plantlets are hardened to adapt to field conditions before being transferred to soil.

**Final Answer**: The method of raising new plants in large numbers from a small plant tissue over a culture medium is **B. Micropropagation / Tissue culture**.

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