Which one is used as a biofertiliser?

Options

A. Nostoc
B. Funaria
C. Volvox
D. Rhizopus

Answer

**Step-by-Step Solution:**

1. **Understanding Biofertilizers**:
- Biofertilizers are defined as substances that contain living microorganisms which promote plant growth by increasing the supply of nutrients to the host plant. They are particularly known for their ability to fix atmospheric nitrogen, making it available to plants.

2. **Identifying the Options**:
- The options provided are:
- Nostoc
- Funaria
- Volvox
- Rhizopus

3. **Analyzing Each Option**:
- **Nostoc**: This is a type of blue-green algae (cyanobacteria) that is known for its ability to fix atmospheric nitrogen into ammonia, which can then be utilized by plants. This characteristic makes it a suitable candidate for a biofertilizer.
- **Funaria**: This is a bryophyte (moss) and does not have the capability to fix nitrogen.
- **Volvox**: This is a green algae and is not known for nitrogen fixation.
- **Rhizopus**: This is a saprophytic fungus that decomposes organic matter and does not contribute to nitrogen fixation.

4. **Conclusion**:
- Among the given options, Nostoc is the only organism that acts as a biofertilizer due to its nitrogen-fixing ability.

5. **Final Answer**:
- The correct answer is **Nostoc**.

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