Cyanobacteria are useful biofertilisers in the fields of

Options

A. Wheat
B. Maize
C. Rice
D. Sugarcane

Answer

**Step-by-Step Solution:**

1. **Understanding Cyanobacteria**: Cyanobacteria are photosynthetic microorganisms that can fix atmospheric nitrogen into a form usable by plants. They play a crucial role in enhancing soil fertility.

2. **Role as Biofertilizers**: Unlike chemical fertilizers, biofertilizers like cyanobacteria improve soil fertility through biological processes. They contribute to the nitrogen content of the soil, which is essential for plant growth.

3. **Nitrogen Fixation**: Cyanobacteria convert atmospheric nitrogen (N₂) into ammonia (NH₃) through the process of nitrogen fixation. This process enriches the soil with nitrogen, which is a vital nutrient for plants.

4. **Specific Crops**: Cyanobacteria are particularly effective as biofertilizers in certain crops. They are known to be beneficial in the fields of rice (paddy fields), beet, maize, and sugarcane.

5. **Example of Cyanobacteria**: One well-known example of cyanobacteria is Anabaena. Anabaena often forms a symbiotic relationship with the aquatic fern Azolla, enhancing nitrogen fixation in rice fields.

6. **Impact on Crop Yield**: The incorporation of cyanobacteria into agricultural practices not only improves soil fertility but also increases the yield of crops, particularly rice.

**Final Answer**: Cyanobacteria are useful biofertilizers in the fields of rice, maize, beet, and sugarcane.

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