Which one of the following microbes forms symbiotic association with plants and helps them in their nutrition

Options

A. Azotobacter
B. Aspergillus
C. Glomus
D. Trichoderma

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks which microbe forms a symbiotic association with plants and aids in their nutrition. Symbiotic relationships are beneficial interactions between two different organisms.

2. **Identifying the Options:**
The options provided are:
- Azotobacter
- Aspergillus
- Glomus
- Trichoderma

3. **Analyzing Each Option:**
- **Azotobacter:** This is a free-living nitrogen-fixing bacterium, but it does not form a symbiotic relationship with plants.
- **Aspergillus:** This is a genus of fungi, but it does not typically form a symbiotic relationship with plants for nutrition.
- **Glomus:** This is a genus of fungi that forms mycorrhizal associations with plant roots, which is a well-known symbiotic relationship that aids in nutrient absorption.
- **Trichoderma:** This is a genus of fungi that is beneficial in agriculture but does not form a symbiotic association with plant roots for nutrition.

4. **Identifying the Correct Answer:**
Based on the analysis, **Glomus** is the correct answer as it forms a symbiotic association with plant roots, enhancing nutrient uptake, particularly phosphorus, and improving soil fertility.

5. **Conclusion:**
Therefore, the microbe that forms a symbiotic association with plants and helps them in their nutrition is **Glomus**.

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