The method of producing large number of plants in very short duration using plant explants by tissue culture is called

Answer

**Step-by-Step Solution:**

1. **Understanding the Concept**: The question asks about a specific method used in plant tissue culture to produce a large number of plants in a short time. This method is crucial in agriculture and horticulture for rapid propagation.

2. **Identifying the Method**: The method referred to in the question is known as "micropropagation." This term is derived from the small size of the plantlets produced during this process.

3. **Explaining Micropropagation**: Micropropagation involves using plant explants (small pieces of plant tissue) to grow new plants. This technique allows for the rapid multiplication of plants by creating multiple plantlets from a single source plant.

4. **Subculture Process**: In micropropagation, the explants are repeatedly subcultured in a nutrient medium. This means that the plant tissue is transferred to new growth media to encourage the formation of more plantlets.

5. **Types of Micropropagation**: There are several methods of micropropagation, including:
- **Meristem Culture**: Using meristematic tissues as explants.
- **Callus Culture**: Inducing a mass of undifferentiated cells (callus) from the explants.
- **Suspension Culture**: Growing plant cells in a liquid medium.
- **Embryo Culture**: Culturing embryos to develop into plants.
- **Protoplast Culture**: Culturing cells without their cell walls.

6. **Conclusion**: The method of producing a large number of plants in a short duration using plant explants by tissue culture is called **micropropagation**.

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