Question

Dikaryon formation occurs in
(a)Phycomycetes and slime molds
(b)Ascomycetes and slime molds
(c)Ascomycetes and Basidiomycetes
(d)Phycomycetes and Basidiomycetes

Answer 1

Hint: They belong to the subkingdom Dikarya that is the group of higher fungi and is the largest phylum and divisions of the kingdom fungi.

Complete answer:
The dikaryon is a feature of the nucleus which is found in fungi unique to various species. It is a primitive character in the subkingdom Dikarya, which includes both the Ascomycetes and Basidiomycetes. The croziers of ascomycetes and the clamp collection of basidiomycetes are responsible for the maintenance of dikaryon.

Additional Information:
 -Dikaryons are present in many fungi except the green algae Derbesia.
-The exception of green algae was challenged after the heterokaryotic hypothesis (multinucleated cells with different nuclei).
-In ascomycetes crozier (structure formed at the base of asci) is required to form dikaryons.
-In basidiomycetes clamp collection (hook-like structure formed by hyphal cells) is required to form dikaryons.
-Ascomycetes are also known as sac fungi. It is the largest phylum of fungi.
-It's characteristic feature is the formation of non-motile spores called ascospores.
-Basidiomycetes are also known as the club fungi, due to the production of the spores that are club-shaped.
-Basidiomycetes are the filamentous fungi with hyphae and form club-shaped cells called basidia for sexual reproduction.
-The basidia contain specialized spores called basidiospores.

So, the correct answer is ‘Ascomycetes and Basidiomycetes’.

Note: The term dikaryon is derived from the Greek word di meaning ‘two’ and karyon meaning ‘nut’. It is in the context of the cell nucleus. The phylum fungi were discovered by an American biologist R. H. Whittaker. He stated that the fungi are different from other eukaryotes in several aspects. So, in his five-kingdom classification, Whittaker added a separate phylum for fungi.