Protoplast fusion causes :-

Options

A. Rapid growth of off spring
B. Somatic hybridization
C. Production of useful allopolyploid
D. Both (2) and (3)

Answer

### Step-by-Step Solution:

1. **Understanding Protoplast Fusion**:
- Protoplast fusion is a biotechnological technique that involves the fusion of protoplasts (the living part of plant cells without their cell walls) from two different plant species or varieties. This technique is used to create hybrids that can possess desirable traits from both parent plants.

2. **Identifying the Effects of Protoplast Fusion**:
- The question asks what protoplast fusion causes. The potential effects include:
- Rapid growth of offspring
- Somatic hybridization
- Production of useful allopolyploids
- Both somatic hybridization and production of useful allopolyploids

3. **Evaluating Each Option**:
- **Rapid Growth of Offspring**: This is not a direct result of protoplast fusion. While hybrids may grow quickly, the fusion itself does not guarantee rapid growth.
- **Somatic Hybridization**: This is a key outcome of protoplast fusion, as it involves the combination of somatic cells from different plants to create a hybrid.
- **Production of Useful Allopolyploids**: Protoplast fusion can lead to the formation of allopolyploids, which are hybrids that contain more than two sets of chromosomes from different species.
- **Both Somatic Hybridization and Production of Useful Allopolyploids**: Since both of these outcomes are correct, this option is valid.

4. **Conclusion**:
- The correct answer is the fourth option: **Both somatic hybridization and production of useful allopolyploids** are caused by protoplast fusion.

### Final Answer:
Protoplast fusion causes both somatic hybridization and production of useful allopolyploids.

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