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There’s a FUNGUS among us!

There’s a FUNGUS among us!. Mycena lux-coeli. Historically. “true fungi” Oomycetes Slime Molds. Oomycota . include the so-called water molds and downy mildews filamentous protists

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There’s a FUNGUS among us!

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  1. There’s a FUNGUS among us! Mycena lux-coeli

  2. Historically • “true fungi” • Oomycetes • Slime Molds

  3. Oomycota • include the so-called water molds and downy mildews • filamentous protists • "Oomycota" means "egg fungi," and refers to the large round oogonia, or structures containing the female gametes (as shown)

  4. Oomycetes • feed on decaying matter like fungi • parasites on both plants and animals • root rot, blister rusts, downy mildews, lesions on fish, farm animals, & humans • Now placed in the Kingdom Chromista

  5. Oomycetes: Historical Importance • Phytophthora infestans : late blight of Potato – Irish potatofamine • Plasmopara viticola : downy mildew of grapes – nearly wiped out French wine industry – discovery of the first fungicide

  6. Slime Molds (Photographs by Michel Poulain) • life cycle that superficially resembles that of the true fungi • Now placed in the kingdom Protista • Three main groups • Plasmodial • Cellular • Slime nets

  7. Plasmodial Slime Molds • Basically enormous single cells with thousands of nuclei • They are formed when individual flagellated cells swarm together and fuse

  8. Cellular Slime Molds • Spend most of their lives as separate single-celled amoeboid protists • Individual cells aggregate into a great swarm after release of a chemical signal

  9. Labyrinthulomycota • little known about this group • Possess a structure called a net-plasmodium during the vegetative stage • have an organelle called a bothrosome capable of secreting a membrane outside their cells • Cause a disease of sea grasses

  10. What are True FUNGI? • Eukaryotic organisms • Heterotrophic, lacking chlorophyll • Obtain nutrients via enzyme secretion and absorption of resulting byproducts • Cells walls containing chitin and beta glucans • Glycogen as primary food storage

  11. More About Fungi • Can reproduce both sexually and asexually • Heterotrophic – as such can consume almost any carbonaceous substrate including jet fuel and wall paint • Biggest role is in the recycling of dead plant material

  12. Relationships More closely related to animals than to plants Emerged onto dry land about the same time as plants. Myccorhizal relationships likely date from this time as well. Four divisions One form-division

  13. Basidiomycete Life Cycle

  14. Divisions • Chytridiomycota • Zygomycota • Ascomycota • Basidiomycota • Dueteromycota

  15. Chytridiomycota • Aquatic • Flagellated gametes • Basal group in kingdom • Oldest known fungal fossil found in northern Russia – from the Devonian Period (650-543 mya)

  16. Zygomycota • Sexual reproduction via production of a zygospore • Asexual reproduction common • Occur on a wide variety of substrates • May be saprophytic or parasitic

  17. Ascomycota • The “Sac Fungi” • Account for ca. 75% of all described fungi • Spores produced in ASCI (ascus) – typically 8 ascospores produced • Sexual reproduction female gametangia grow toward male gametangia

  18. Ascomycota cont. • True truffles, morels, cup fungi, most lichens • Yeasts (Saccharomyces cerevisiae – used in baking and brewing) • Chestnut Blight (Cryphonectria parasitica), Dutch Elm Disease (ophiostoma ulmi), Pneumonia (Pneumocystis carinii) • Aspergillus flavus – produces aflatoxin (the most powerful known carcinogen and toxin)

  19. Basidiomycota • Gametangia not formed, nuclear material exchanged in various ways • Many have clamp connections • Spores produced on Basidia (basidium) • Mushrooms (toadstools), puffballs, jelly fungi, bird nest fungi, bracket, smuts, rusts, and stinkhorns • Oldest known fossil from New Jersey Amber dating from the Cretaceous age (90-95 mya)

  20. Basidiomycota cont. • Play significant role in the carbon cycle • Form ectomycorrhizal partnerships (principally with forest trees) and symbiotic relationships • Divided into three major groups

  21. Clamp connection

  22. Fossil

  23. Deuteromycota • Form-group, artificial grouping • Sexual reproduction stage unknown (maybe lost) • Members transferred to proper group when sexual stage is observed • Penicillium, Aspergillus

  24. Lichens • Symbiotic relationship between a fungal partner and photosynthetic autotroph (typically an alga or cyanobacterium) • Fungal partners tend to be Ascomycetes • Sensitive to air pollution • Several forms – crustose (flat and crust-like), foliose (leaf-like, loosely attached to the substrate), fruticose (strap shaped to cylindrical, upright or pendulous); intermediate forms common • Typically divided into 1 or more layers internally

  25. Lichens cont. • Identification based on form, layers, color, chemical tests, and substrate • Play a significant role in nitrogen fixation, water absorption and retention, and soil building • Are a major part of the cryptobiotic soils of desert regions • Slow growth rates – age often measured in decades or centuries

  26. Crustose Lichens

  27. Foliose Lichens

  28. Fruticose Lichens

  29. Fungal Ecology • Saprobe decomposer of all terrestrial organic matter (and some aquatic matter) • Pathogen purveyor of plant and animal disease • Mycorrhizae symbiosis of plant and fungus (fungi)

  30. The term mycorrhiza, which literally means fungus-root first applied to fungus-tree associations described in 1885 95% of all plant species Mycorrhizae

  31. Mycorrhizae Cont. • Symbiotic associations that form between the roots of most plant species and fungi • characterized by bi-directional movement of nutrients where carbon flows to the fungus and inorganic nutrients move to the plant

  32. HYPHAE Twinetogether to form large masses called mycelium (Some even glow in the dark, as in this Mycena)

  33. septa hyphae

  34. Ascocarp Basidiocarp Elegant designs for spore dispersal Wind dispersal Water dispersal Animal dispersal Fruiting Bodies

  35. Ascocarp

  36. Basidiocarp

  37. Wind Dispersed

  38. Water Dispersed

  39. Animal Dispersal

  40. Fungal Structure • Pileus • Stipe • Hymenium surface • Ascomycete -vs- Basidiomycete

  41. The Pileus The mycological way of saying a cap Yes, you will need to know the proper name

  42. Pileus Features

  43. Stipe The mycological name for the stem Not always present !!!

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