Which of the following microbes serve as an important biofertiliser in paddy fields ?

Options

A. Glomus
B. Azotobacter
C. Anabaena
D. Rhizobium

Answer

To determine which microbe serves as an important biofertilizer in paddy fields, we can analyze the options provided:

1. **Glomus**: This is a genus of fungi that forms arbuscular mycorrhizal associations with plants. While beneficial for plant growth, it is not specifically known for use in paddy fields as a biofertilizer.

2. **Azotovector**: This is a genus of bacteria that can fix nitrogen, but it is not commonly recognized as a significant biofertilizer in paddy fields.

3. **Anabina**: This is a genus of cyanobacteria (also known as blue-green algae) that is known for its ability to fix atmospheric nitrogen. Anabina can be found in association with the water fern Azolla, which is often used in rice cultivation. It plays a crucial role in enhancing soil fertility by fixing nitrogen, making it an important biofertilizer in paddy fields.

4. **Rhizobium**: This is a genus of bacteria that forms symbiotic relationships with legumes, fixing nitrogen in root nodules. While it is an important biofertilizer, it is not specifically used in paddy fields.

Based on this analysis, the correct answer is **Anabina**, as it is a significant biofertilizer in paddy fields due to its nitrogen-fixing capabilities.

### Final Answer:
The microbe that serves as an important biofertilizer in paddy fields is **Anabina**.