AM Fungi mostly increase

Options

A. Phosphate absorption
B. Potassium absorption
C. Nitrogen absorption
D. Both phosphate and nitrogen absorption

Answer

**Step-by-Step Solution:**

1. **Understanding AM Fungi**: AM fungi stands for Arbuscular Mycorrhizal fungi. They form a symbiotic relationship with the roots of plants, helping them absorb nutrients from the soil.

2. **Identifying the Role of AM Fungi**: These fungi are particularly important in nutrient-deficient soils, such as volcanic soils, where they enhance the availability of essential nutrients to plants.

3. **Nutrient Absorption**: The primary function of AM fungi is to increase the absorption of nutrients, particularly phosphate, from the soil. They extend their hyphae into the soil, which increases the surface area for nutrient uptake.

4. **Symbiotic Relationship**: In this symbiotic relationship, the fungi absorb phosphate from the soil and transfer it to the plant roots. In return, the plant provides carbohydrates to the fungi, which they need for energy.

5. **Conclusion**: Based on the information, AM fungi mostly increase phosphate absorption in plants. Therefore, the correct answer to the question is option A: phosphate absorption.

**Final Answer**: AM fungi mostly increase phosphate absorption.

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