Farmers have reported over `50%` higher yield of rice by using which of the following biofertilizer?

Options

A. Mycorrhiza
B. Anabaena azollae
C. Lichen
D. Legume-rhizome symbiosis

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which biofertilizer has led to a reported increase of over 50% in rice yield by farmers.

2. **Analyzing the Options**: The options provided are:
- A) Mycorrhizae
- B) Anabena and Azolla
- C) Lichen
- D) Legume-Rhizobium Symbiosis

3. **Identifying the Correct Biofertilizer**:
- **Mycorrhizae**: This is a symbiotic association between fungi and plant roots, which helps in nutrient absorption but is not specifically known for increasing rice yield by 50%.
- **Anabena and Azolla**: Azolla is a free-floating water fern that can fix atmospheric nitrogen in association with Anabena, a nitrogen-fixing blue-green algae. This combination is known to significantly enhance rice yields by providing an alternative nitrogen source.
- **Lichen**: This is a symbiotic relationship between fungi and algae, but it is not specifically related to rice yield enhancement.
- **Legume-Rhizobium Symbiosis**: While this is an important nitrogen-fixing relationship, it is not directly related to rice cultivation.

4. **Conclusion**: Based on the analysis, the correct answer is **Option B: Anabena and Azolla**. This combination is known to contribute to a significant increase in rice yield due to its ability to fix nitrogen.

5. **Final Answer**: Farmers have reported over 50% higher yield of rice by using **Anabena and Azolla**.

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