In which of the following pair the occurrence of dikaryophase of fungus can be observed ?

Options

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

Answer

To solve the question regarding the occurrence of dikaryophase in fungi, we will analyze the options provided step by step.

### Step-by-Step Solution:

1. **Understanding Dikaryophase**:
- The dikaryophase is a stage in the life cycle of certain fungi where two genetically distinct nuclei coexist in the same cell. This phase occurs after plasmogamy (fusion of cytoplasm) and before karyogamy (fusion of nuclei).

2. **Identifying Fungal Groups**:
- The question mentions different groups of fungi: Ascomycetes, Basidiomycetes, and Phycomycetes.
- Ascomycetes and Basidiomycetes are known to have a dikaryophase in their life cycle.

3. **Evaluating the Options**:
- **Option 1: Ascomycetes and Basidiomycetes**:
- This is the correct pair. Both groups exhibit a dikaryophase where the nuclei remain separate for a period.
- **Option 2: Phycomycetes and Ascomycetes**:
- This option is incorrect. Phycomycetes do not have a dikaryophase.
- **Option 3: Phycomycetes and Basidiomycetes**:
- This option is also incorrect for the same reason as above; Phycomycetes do not exhibit a dikaryophase.
- **Option 4: Basidiomycetes and Basidiomycetes**:
- This option is redundant and incorrect as it does not provide a valid pair.

4. **Conclusion**:
- The only valid pair where the occurrence of dikaryophase can be observed is **Ascomycetes and Basidiomycetes**.

### Final Answer:
The correct answer is **Option 1: Ascomycetes and Basidiomycetes**.

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