Dikaryotic cells are formed in

Options

A. Phycomycetes
B. Ascomycetes
C. Basidiomycetes
D. Both B and C.

Answer

### Step-by-Step Solution:

1. **Understanding Dikaryotic Cells**:
- Dikaryotic cells are characterized by having two distinct haploid nuclei within a single cell. This condition arises during the sexual reproduction of certain fungi.

2. **Identifying Fungal Groups**:
- The question asks where dikaryotic cells are formed. The relevant groups of fungi are:
- Phycomycetes
- Ascomycetes (Escomycetes)
- Basidiomycetes

3. **Analyzing Phycomycetes**:
- In Phycomycetes, the process of sexual reproduction involves the fusion of both the cytoplasm and the nuclei of two hyphae. This results in a diploid nucleus rather than a dikaryotic condition. Therefore, dikaryotic cells are **not formed** in Phycomycetes.

4. **Analyzing Ascomycetes and Basidiomycetes**:
- In both Ascomycetes and Basidiomycetes, the process of plasmogamy occurs. Plasmogamy is the fusion of the cytoplasmic contents of two hyphae, but the nuclei remain separate initially. This results in dikaryotic hyphae, where each cell contains two haploid nuclei, one from each parent.

5. **Conclusion**:
- Since dikaryotic cells are formed in both Ascomycetes and Basidiomycetes, the correct answer to the question is **both B and C**.

### Final Answer:
Dikaryotic cells are formed in **Ascomycetes and Basidiomycetes** (both B and C).

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