Dikaryon formation is characteristic of

Options

A. Ascomycetes and Basidiomycetes
B. Phycomycetes and Ascomycetes
C. Basidiomycetes and Zygomycetes
D. Phycomycetes and Deuteromycetes

Answer

To solve the question regarding the characteristic formation of dikaryons, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Dikaryon Formation**:
- A dikaryon is a fungal cell that contains two genetically distinct nuclei. This condition is significant in the life cycle of certain fungi.

2. **Identifying the Fungal Groups**:
- Dikaryon formation is primarily associated with two major groups of fungi: Ascomycetes and Basidiomycetes.

3. **Process of Dikaryon Formation**:
- In fungi, sexual reproduction involves two key processes: plasmogamy and karyogamy.
- Plasmogamy is the fusion of the cytoplasm of two parent cells, which leads to the formation of a dikaryotic stage where two nuclei coexist in a single cell.
- Karyogamy is the subsequent fusion of these two nuclei, resulting in a diploid cell.

4. **Conclusion**:
- Since dikaryon formation is characteristic of both Ascomycetes and Basidiomycetes, we conclude that the correct answer to the question is that dikaryon formation is characteristic of these two groups of fungi.

### Final Answer:
Dikaryon formation is characteristic of **Ascomycetes and Basidiomycetes**.

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