Question

Dikaryon formation occurs in

• A. Phycomycetes and slime moulds
• B. Ascomycetes and Basidiomycetes
• C. Phycomycetes and Basidiomycetes
• D. Ascomycetes and slime moulds

Answer 1

The correct option is B

Ascomycetes and Basidiomycetes

The correct option is B.
Explanation for correct option:

1. Dikaryon is an inbetweeen stage and mode of reproduction is sexual in fungi especially in basidiomycetes and ascomycetes.
2. In this condition a cell has two nucleus.
3. Mating results in a dikaryon phase which is intervening between plasmogamy and Karyogamy stage.

Explanation for incorrect options:
Option A

1. In phycomycetes and slime moulds, no dikaryon formation occurs.
2. In phycomycetes, a sexual reproduction takes place by zoospores or by aplanospores. Zygospore is formed by the fusion of two gametes. That's why it is an incorrect option.

Option C

1. In phycomycetes, zoospore formation takes place by the fusion of a motile and a non-motile spore.
2. No dikaryon stage occurs. That's why it is an incorrect option.

Option D

1. Slime moulds produces spores.They are saprophytic in nature and feed on dead and decaying matter.
2. They are kept under protista Kingdom. That's why it is an incorrect option.

Final answer: Dikaryon formation occurs in Ascomycetes and basidiomycetes.