In Paddy fields which microorganism serve as important biofertiliser?

Answer

**Step-by-Step Solution:**

1. **Understanding Biofertilizers**: Biofertilizers are defined as living organisms that, when added to soil, enhance its fertility. They contribute to the nutrient content of the soil, which is essential for plant growth.

2. **Microorganisms in Paddy Fields**: In the context of paddy fields, specific microorganisms act as biofertilizers. These microorganisms help in improving the soil's fertility, which is crucial for the cultivation of rice.

3. **Identifying Key Microorganisms**: The primary microorganisms that serve as biofertilizers in paddy fields are cyanobacteria, also known as blue-green algae. These organisms play a significant role in enriching the soil.

4. **Function of Cyanobacteria**: Cyanobacteria contribute to the soil by adding organic matter and fixing atmospheric nitrogen, which increases the nutrient availability for plants. This process ultimately leads to improved crop yields.

5. **Examples of Cyanobacteria**: Common examples of cyanobacteria found in paddy fields include Oscillatoria, Anabaena, and Nostoc. These species are known for their effectiveness as biofertilizers.

6. **Conclusion**: Therefore, the microorganisms that serve as important biofertilizers in paddy fields are cyanobacteria, or blue-green algae.

**Final Answer**: Cyanobacteria (blue-green algae) serve as important biofertilizers in paddy fields.

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