Read the statements carefully
a. Hartig net is the network of intracellular mycellium of Boletus
b. Ectomycorrhiza forms ten percent of total mycorrhiza
c. Fungal partner of endomycorrhiza belongs to zygomycetes or phycomycetes

Options

A. Only a & c are correct
B. Only b & c are correct
C. Only c is correct
D. All are correct

Answer

To solve the question, we need to evaluate each of the three statements provided about mycorrhizae and fungi.

### Step-by-Step Solution:

1. **Evaluate Statement A**:
- The statement claims that the Hartig net is the network of intracellular mycelium of Boletus.
- The Hartig net is actually associated with ectomycorrhizae, which are not found in Boletus. Boletus is a type of mushroom that does not form a Hartig net. Therefore, this statement is **incorrect**.

2. **Evaluate Statement B**:
- This statement asserts that ectomycorrhiza forms ten percent of total mycorrhiza.
- Ectomycorrhizae indeed represent about 10% of all mycorrhizal associations, while endomycorrhizae make up the remaining 90%. Thus, this statement is **correct**.

3. **Evaluate Statement C**:
- The statement claims that the fungal partner of endomycorrhiza belongs to zygomycetes or phycomycetes.
- Endomycorrhizae are primarily associated with fungi from the phylum Glomeromycota, which includes arbuscular mycorrhizal fungi. Zygomycetes and phycomycetes are not the main groups associated with endomycorrhizae. Therefore, this statement is **incorrect**.

### Conclusion:
- The correct statements are only **B**. Therefore, the answer is that only statement B is correct.

### Final Answer:
- Only statement B is correct.

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