In ectomycorrhiza, the fungus is generally

Options

A. Zygomycete
B. Phycomycete
C. Ascomycete
D. Basidiomycete

Answer

### Step-by-Step Solution:

1. **Understanding Ectomycorrhiza:**
- Ectomycorrhiza refers to a symbiotic association between fungi and the roots of certain plants. In this relationship, the fungus forms a sheath around the root and extends into the soil, aiding in nutrient absorption for the plant.

2. **Identifying the Types of Fungi:**
- The question asks about the type of fungi typically associated with ectomycorrhiza. The options provided are:
- Zygomycetes
- Phycomycetes
- Ascomycetes
- Basidiomycetes

3. **Analyzing Each Option:**
- **Zygomycetes:** These fungi are primarily known for their role as endomycorrhizal fungi, which means they form associations inside the root cells, not outside. Therefore, this option is incorrect.
- **Phycomycetes:** These fungi are generally saprophytic, meaning they feed on dead organic matter. They do not typically form ectomycorrhizal associations, making this option incorrect as well.
- **Ascomycetes:** This group of fungi can form ectomycorrhizal relationships and is often found in various habitats, including marine environments.
- **Basidiomycetes:** Similar to Ascomycetes, Basidiomycetes are also known to form ectomycorrhizal relationships, particularly with trees and other plants.

4. **Conclusion:**
- The correct answers are Ascomycetes and Basidiomycetes, as both types of fungi are known to form ectomycorrhizal associations with plants.

### Final Answer:
In ectomycorrhiza, the fungus is generally **Ascomycetes and Basidiomycetes**.

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