AgriMyc

Sac fungi

Introduction

Sack fungi (Ascomycota) or ascomycetes are the largest phylum in the kingdom of fungi (Fungi) and contain about 65,000 described species. These species include i.a. morels, truffles, cap fungi and yeast and mold. The vast majority of fungi, which live in symbiosis with algae and form lichens, also belong to Ascomycota, as well as many veterinarily important fungi.

Sexual reproduction

What characterizes many members of Ascomycota is a microscopic structure for sexual reproduction, called the ascus (meaning sac), where immobile spores (so-called ascospores) are formed. These species are said to be teleomorphic, which refers to the sexual reproduction stage of the fungal life cycle. 

Asexual reproduction

Some species within Ascomycota are asexulla (lack sexual reproduction) and thus do not form ascospores. They are, therefore, called anamorphic species and anamorph is thus an asexual stage of reproduction in the life cycle of the fungi.

Asexual reproduction can take place with the help of so-called conidia (= conidiospores), which is a form of spores, which have been formed asexually by mitosis. Mitosis is the form of cell division that gives rise to two genetically identical daughter cells, with the same number of chromosomes as the original cell.

By holomorph is meant the entire fungus (all life cycles). The terms anamorph, holomorph and teleomorph are used for sac fungi and basidiomycetes. The concepts have given rise to confusion when it comes to naming fungi, because an anamorphic fungus has been given a certain scientific name, but unfortunately another scientific name is given to the teleomorphic fungus of the same species. On the fungus pages of AgriMyc, one can generally find both names. 

Budding

Asexual reproduction can also take place through budding and yeasts are unicellular fungi, which often multiply asexually by budding of small "daughter cells". These can sometimes hang on to the mother cell and then form a short chain, which is called a pseudohypha.

Updated: 2022-03-17.