In which of the following , asexual spores are generally not seen, but there is the development of dikaryophase stage ?

Options

A. Albugo
B. Claviceps
C. Alternaria
D. Agaricus

Answer

To solve the question, we need to identify which of the given options does not produce asexual spores but does exhibit a dikaryophase stage. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Terms
- **Dikaryophase Stage**: This is a stage in the life cycle of certain fungi where two nuclei coexist in a single cell, represented as n + n. This stage is typically found in homothallic species of fungi.
- **Asexual Spores**: These are spores that are produced without sexual reproduction.

### Step 2: Analyze the Options
1. **Albugo**: This is a type of fungus that belongs to the group of Phycomycetes. It is known to produce asexual spores. Therefore, this option is incorrect.

2. **Claviceps**: This fungus belongs to the Ascomycetes group. It is known to produce sexual spores but does not exhibit a dikaryophase stage because it is heterothallic (the two gametes are genetically dissimilar). Thus, this option is also incorrect.

3. **Alternaria**: This is another fungus belonging to the Ascomycetes group. Similar to Claviceps, it produces asexual spores and does not exhibit a dikaryophase stage. Hence, this option is incorrect as well.

4. **Agaricus**: This fungus belongs to the Basidiomycetes group. It is known to exhibit a dikaryophase stage and is typically homothallic, meaning it can have two genetically similar gametes. Importantly, Agaricus does not primarily produce asexual spores. Therefore, this option is correct.

### Conclusion
Based on the analysis, the correct answer is **Agaricus**, as it does not produce asexual spores but does exhibit a dikaryophase stage.

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