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Home , Hypha, Mycelium, Zygospore

Fungi are organisms that we ..whether you encounter in our know it or not! everyday lives..

Very diverse group of organisms

Tremella mesenterica (Witches Butter)

Athlete’s Foot Metatrichia vesparium (Slimemold)

1 Ring Worm Peltiger venosa

Geastrum tripex (Earthstar) Various cultivated

Roquefort or Blue Cheese Camembert or Brie Cheese

2 Leavened and Unleavened Bread Soy Products

Rhizopus stolonifer () Alcoholic Beverages

But

What is a ?

Aseroe rubra (Stinkhorn)

3 A very ..genetically diverse and in group of appearance organisms..

What is a Fungus? 1.Alexopolous (1952) "nucleated, achlorophyllous organisms which typically reproduce sexually What is a and asexually, and whose usually filamentous branched somatic structures are surrounded by fungus? walls" Excluded slime !

What is a Fungus? What is a Fungus? 2.Alexopolous (1962) 3.Currently, in the sense of "nucleated, achlorophyllous organisms most mycologists??? which typically reproduce sexually and organisms that are nucleated, asexually, and whose usually achlorophyllous, typically reproduce filamentous branched somatic sexually and asexually by , and structures are surrounded by cell whose somatic structure is composed walls" of filamentous branched or , composed of or or which are surrounded by cells walls both composed of chitin Included slime molds! Excludes slime molds and others!

4 Characteristics of Fungi Characteristics of Fungi 1.Heterotrophs 2.Fungus body a.Heterotroph categories: a. (pl.=Hyphae) i.Saprobes (pl.=Mycelia) ii.Parasites iii.Facultative saprobes and b.Yeast parasites iv.Symbionts (mutulalistic)

Characteristics of Fungi Characteristics of Fungi

2.Fungus body a.Hypha (pl.=Hyphae) Mycelium (pl.=Mycelia) i.Coenocytic Mycelium forming circular colony ii.Septate from radial growth (left) and mycelium as observed with microscope (right)

Coenocytic Hypha Septate Hypha Ô Septum (pl.=septa) Ô Ñ Mycelium

5 Characteristics of Fungi 2.Fungus body Yeast Ó b.Yeast: unicellular, asexual reproduction, budding or fission. Ñ c.Dimorphic: Having a yeast Mycelium and mycelium phase in the Rhodotorula:Rhodotorula same fungus. Yeast mesenterica: Dimorphic

3.Reproduce by spores a.Variable in size, shape and color. Sexual or asexual.

Budding Yeast

Spores are often borne directly Spores are not always borne on modified hyphae directly on mycelium.

Fruitbodies, e.g. mushrooms notatum colony and formed from mycelium produce conidia and conidiophore (asexual) spores (sexual).

6 Fruiting Bodies can be of Characteristics of Fungi various shapes, sizes and color 4.Presence of : Chitin and infrequently cellulose 5.: Membrane bound organelles, e.g. nuclei, mitochondria, plasma membrane, etc.

All are composed of tightly interwoven mycelium.

Characteristics of Fungi Characteristics of Fungi 6.Mode of nutrition: Absorption 6.Mode of nutrition: Absorption a. Fungi “live” in their food. b. Digestive enzyme(s) released to f. If food is soluble, e.g., act on Insoluble food. composed of simple c. Break-down (digestion) of food. molecules such as sugars and amino acids, digestive d. Fungi “absorb” (=eat) digested enzymes are not necessary. food. g. Soluble food can be directly e. Only sequence of events differ absorbed into cells. from animal ingestion of food.

Sexual vs. Asexual Summary of Absorption Reproduction 1.Sexual Reproduction a. Two parents required. b. Children borne will all be genetically unique. c. Children will inherit characteristics from both parents.

7 Sexual vs. Asexual Reproduction 2.Asexual Reproduction a. Only one parent is involved. Post Scripts b. Children borne will all be genetically identical to parent.

World’s largest fairy rings:

Mushroom gallica reported on April 2,1992

1.Mycelium (rhizomorph)rhizomorph of covered 37 acres is about 25 ft. in 2.Over 1500 years old. diameter

World’s largest fairy rings: World’s largest fairy rings:

Mushroom Armillaria ostoyae Mushroom Armillaria ostoyae. reported on May 18,1992 1.Rhizomorph of mushroom 1.Rhizomorphs of mushroom covered 2,200 acres covered 1500 acres 2.Over 2400 years old. 2.Age???

8 Misconceptions About Fungi Misconceptions About Fungi

1.Temperature: Fungi grow best 2.Water: Fungi need lots of at warm temperatures water. a. Probably most grow better a. Again, mostly true. But… at 70-90°F., But… b. Some can grow in very dry b. Some can thrive at conditions, e.g. contaminate temperatures of 130-150°F. grains and dried fruits. c. Some can thrive at temperatures c. Some can grow underwater. below 32°F (below freezing).

Misconceptions About Fungi Summary of Characteristics 1.Heterotrophs. 3.Light: Fungi grow best in the dark. 2.Body composed of hypha- a. Light is usually not important mycelium or yeast, or both. in growth of fungi 3.Reproduce by spores b. Some species do have a light 4.Cell Wall, usually of chitin, requirement for reproduction, rarely cellulose. but not for growth. 5.Eukaryotes 6.Mode of nutrition, absorption

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