Sexual reproduction is via conjugation , in which hyphae from different mating types fuse. The life cycle of Neurospora , which has been studied extensively, illustrates this phenomenon. Mating types are genetically dissimilar but can form either male or female structures- hence, they are not different sexes. Note that there are no sperm with motile flagella in any of the fungal life cycles. Diversity of Fungi There are about 100,000 spp. of fungi within three major taxa.
Classification is based on the sexual structures exhibited.
In the life cycle, sexual union between two haploid mating strains produces a resistant structure called a zygospore within which haploid nuclei fuse to form a diploid zygote and meiosis ensues. Subsequently, haploid spores are released. These spores germinate to form new mycelia which produce their own sporangia and spores to continue the asexual cycle. Interestingly, it is known that air borne pheromones participate in sexual reproduction. The reproductive structure formed in this group is the ascus .