Introduction to the major groups of fungi and fungus-like organisms

Although much of fungal taxonomy is in a state of flux, the major groupings remain fairly constant.  You should become familiar with the following groups by careful observation of the representative forms on demonstration.
Kingdoms Protista or Stramenopila
cell walls lacking or made of cellulose.
Myxomycota

Acellular Slime Molds - Assimilative phase is a plasmodium: cell walls lacking.
Dictyosteliomycota
Acrasiomycota
Cellular slime molds.  assimilative phase is amoebae that aggregate into a pseudoplasmodium and a reproductive structure.
Plasmodiophoromycota
Endoparasitic slime molds. all are internal plant parasites, single celled
Oomycota
water molds.  mostly aquatic, some plant parasites. reproductive cells with two flagella
Kingdom Fungi-
       TRUE FUNGI
Assimilative phase typically filamentous or unicellular, cell walls present.
Chytridiomycota

Chytrids. - Unicellular or filamentous with aseptate vegetative hyphae; tend to be aquatic. reproductive cells with one flagellum, vegetative hyphae lack septa
Glomeromycota
Arbuscular mycorrhizal fungi, AMF, endomycorrhizae.  Reproduction via external mitotic spores.
Zygomycota
bread molds, etc. Sexual reproduction by formation of zygospores from fused gametangia; vegetative hyphae lack septa.
Ascomycota
sac fungi:  cup fungi, yeasts, powdery mildews, morels - Sexual spores borne internally in sacs, asci; septate hyphae
Basidiomycota
club fungi: gilled mushrooms, pore fungi, jelly fungi, puffballs, rusts and smuts - Sexual spores borne externally on club-shaped basidia; septate hyphae.
"deuteromycetes"
deuteromycetes—imperfect fungi. No known sexual stages; septate hyphae.

            By the end of this lab you should be able to identify which of these major groups each of the specimens on display represents.  You should be able to do this by paying particular attention to the essential forms of these major taxonomic groups.  Refer to the list of fungi in "A Classification of Major Groups of Fungi" in the preface to your lab manual.  This initial treatment of taxonomy is necessarily superficial.  By the end of the course you will be able to identify most fungi to Order and many to Species.  Such detail is impossible at this time since you are unfamiliar with most of the different life cycles, sexual and asexual reproductive stages, nutritional modes, vegetative growth forms, physiology, genetics, morphology, and ecology that are necessary for complete taxonomy.  It is important that you quickly gain at least superficial understanding of the taxonomy of fungi, since in the long run, much of your further work will be based on this understanding, and in the short term, you will be encountering random representatives of most of these groups in your field work early in the semester.  In order to ensure this understanding, your instructor will provide a short quiz on this material early in the semester.  As you study each group during the semester, fill in the chart on the following pages.








Vegetative forms

Septa
Wall constituents
Asexual reproduction
Dictyosteliomycota
           





Myxomycota





Plasmodiophoromycota





Oomycota




Glomeromycota






Chytridiomycota





Zygomycota





Ascomycota





            Hemiascomycetes






            Plectomycetes





            Pyrenomycetes






            Discomycetes





            Loculoascomycetes






Basidiomycota





                        Hymenomycetes




                        Gasteromycetes





            Urediniomycetes




           
           Ustilaginomycetes





“deuteromycetes”









Sexual Reproduction


Structures for plasmogamy
Site of karyogamy
Structures for sexual spores
Life
Cycles
Major representatives

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