The dikaryon in basidiomycetes is indicative of

Options

A. karyogamy
B. plasmogamy
C. isogamy
D. syngamy

Answer

### Step-by-Step Solution:

1. **Understanding Basidiomycetes**: Basidiomycetes are a group of fungi that reproduce sexually. They are characterized by the presence of specialized structures called basidia, where spores are produced.

2. **Reproductive Process**: In sexual reproduction among basidiomycetes, two genetically different mating types come together and undergo a process of fusion.

3. **Stages of Fusion**: The fusion process in fungi occurs in two main stages:
- **Plasmogamy**: This is the first stage where the cytoplasm of two cells fuses, resulting in a single cell with two distinct nuclei.
- **Karyogamy**: This is the second stage where the nuclei of the two cells fuse together. In basidiomycetes, karyogamy is delayed and occurs just before meiosis.

4. **Dikaryon Formation**: After plasmogamy, the cell contains two nuclei that have not yet fused. This condition is referred to as a dikaryon. The dikaryon stage is characterized by having two nuclei in one cell, which is a unique feature of certain fungi, including basidiomycetes.

5. **Conclusion**: Therefore, the presence of a dikaryon in basidiomycetes is indicative of plasmogamy, as it represents the stage where the cytoplasm has fused but the nuclei remain separate.

### Final Answer:
The dikaryon in basidiomycetes is indicative of **plasmogamy**.

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