Mycorrhiza is used in

Options

A. Obtaining nutrients from soil
B. Synthesis of food
C. Increasing soil fertility
D. Providing resistance against different regulators.

Answer

**Step-by-Step Solution:**

1. **Understanding Mycorrhiza**: Mycorrhiza refers to a symbiotic association between fungi and plant roots. It is important to recognize that mycorrhizae are not just any fungi; they specifically form a beneficial relationship with plants.

2. **Nature of the Relationship**: This association is mutualistic, meaning both the fungi and the plants benefit from it. The fungi help the plants absorb nutrients and water from the soil, while the plants provide carbohydrates and other organic substances to the fungi.

3. **Role in Plant Nutrition**: Mycorrhizae play a crucial role in enhancing plant nutrition. They increase the surface area for absorption, allowing plants to access more nutrients (like phosphorus and nitrogen) and water from the soil than they would be able to on their own.

4. **Conclusion**: Based on the above points, we can conclude that mycorrhizae are primarily used to help plants obtain nutrients and water from the soil effectively.

5. **Final Answer**: Therefore, the correct answer to the question "Mycorrhiza is used in" is that it helps in obtaining nutrients from the soil.

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