Dikaryophase is a specific characteristic of

Options

A. all Fungi
B. phycomycetes and Ascomycetes
C. Basidiomycetes and Deuteromycetes
D. Ascomycetes and Basidiomycetes.

Explanation

To solve the question regarding the dikaryophase, we can break down the information step by step:

### Step-by-Step Solution:

1. **Understanding Dikaryophase**:
- The dikaryophase is a specific stage in the life cycle of certain fungi. It occurs after the process of plasmogamy, where two fungal cells fuse, but before karyogamy, where the nuclei fuse.

2. **Definition of Key Terms**:
- **Plasmogamy**: The fusion of the cytoplasm of two cells.
- **Karyogamy**: The fusion of two nuclei.
- **Dikaryon**: A cell that contains two genetically distinct nuclei (n + n).

3. **Identifying the Organisms**:
- The question provides four options:
1. All fungi
2. Phycomycetes and Ascomycetes
3. Basidiomycetes and Deuteromycetes
4. Ascomycetes and Basidiomycetes

4. **Analyzing the Options**:
- The dikaryophase is particularly characteristic of Ascomycetes and Basidiomycetes, where the dikaryotic stage is a significant part of their life cycle.

5. **Conclusion**:
- Based on the understanding that the dikaryophase occurs specifically in Ascomycetes and Basidiomycetes, the correct answer is option 4: Ascomycetes and Basidiomycetes.

### Final Answer:
The dikaryophase is a specific characteristic of **Ascomycetes and Basidiomycetes** (Option 4).

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