In some fungi, the fusion of two haploid cells does not immediately result in a diploid cell (2n). Instead, an intervening dikaryotic stage (n + n) occurs before the nuclei fuse. Which of the following pairs of fungal classes distinctly exhibits this prolonged dikaryophase?

Step-by-step solution

In certain fungi, the fusion of two haploid cells immediately results in diploid cells (2n), which is characteristic of lower fungi like Phycomycetes. However, according to NCERT, in Ascomycetes and Basidiomycetes, plasmogamy is not immediately followed by karyogamy. This creates an intervening dikaryotic stage (n + n, i.e., two nuclei per cell) known as a dikaryon, and the phase is called the dikaryophase. Deuteromycetes are known as imperfect fungi because only their asexual or vegetative phases are known, and a