The organisms which are used to enrich the nutrient quality of the soil are called

Options

A. mycorrhiza
B. biofertilizers
C. Yeast
D. methanogens

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the organisms that are used to enrich the nutrient quality of the soil. This involves identifying specific types of organisms that contribute to soil fertility.

2. **Identifying Key Organisms**:
- **Mycorrhizae**: These are symbiotic associations between fungi and plant roots. They enhance nutrient absorption, particularly phosphorus, and improve soil structure.
- **Bio-fertilizers**: These are composed of living microorganisms, including bacteria and algae, that promote plant growth by increasing the availability of nutrients in the soil.
- **Yeast**: This unicellular fungus can also contribute to soil health by breaking down organic matter and enhancing nutrient availability.
- **Methanogenesis**: This refers to a group of anaerobic bacteria that produce methane. While they are primarily known for their role in anaerobic digestion, they also contribute to nutrient cycling in the soil.

3. **Conclusion**: The organisms that enrich the nutrient quality of the soil include mycorrhizae, bio-fertilizers (which consist of bacteria and algae), yeast, and methanogenic bacteria.

**Final Answer**: The organisms which are used to enrich the nutrient quality of the soil are called **bio-fertilizers**, **mycorrhizae**, **yeast**, and **methanogenic bacteria**.

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