Which of the following is not an application of plant tissue culture?

Options

A. Propagation of a large number of plants in very short durations
B. Changing the ploidy of plant
C. Płoducing plants which are genetically identical to the parent plant
D. Recovery of healthy plants from the diseased plants

Answer

To solve the question "Which of the following is not an application of plant tissue culture?", we will analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understand Plant Tissue Culture**:
- Plant tissue culture is a technique used to grow plant cells, tissues, or organs under sterile conditions on a nutrient culture medium.
- It is primarily used for propagation, genetic modification, and disease recovery.

2. **Evaluate Each Option**:
- **Option A**: Propagation of a large number of plants in a very short duration.
- This is a well-known application of plant tissue culture. It allows for rapid multiplication of plants.
- **Conclusion**: This option is an application of plant tissue culture.

- **Option B**: Changing the ploidy of the plant.
- While plant tissue culture can be used for various genetic manipulations, changing the ploidy level (the number of sets of chromosomes) is not a direct application of tissue culture techniques.
- **Conclusion**: This option is NOT an application of plant tissue culture.

- **Option C**: Producing plants which are genetically identical to the parent plant.
- This is a fundamental aspect of plant tissue culture, as it allows for cloning of plants, resulting in genetically identical offspring.
- **Conclusion**: This option is an application of plant tissue culture.

- **Option D**: Recovery of healthy plants from diseased plants.
- Plant tissue culture can be used to recover healthy plants by using meristematic tissues that are free from pathogens.
- **Conclusion**: This option is an application of plant tissue culture.

3. **Identify the Correct Answer**:
- After evaluating all options, it is clear that **Option B (changing the ploidy of the plant)** is not an application of plant tissue culture.

### Final Answer:
The correct answer is **Option B: Changing the ploidy of the plant**.

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