1. Kingdom Fungi

2. The Characteristics of Fungi
Fungi are NOT plants
Nonphotosynthetic
Eukaryotes
Nonmotile
Most are saprobes (live on dead organisms)
Absorptive heterotrophs
Release digestive enzymes to break down organic material

3. The Characteristics of Fungi
Important decomposers & recyclers of nutrients in the environment
Most are multicellular, except unicellular yeast
Lack true roots, stems or leaves
Cell walls are made of chitin (complex polysaccharide)
Body is called the Thallus
Grow as microscopic tubes or filaments called hyphae
UNICELLULAR YEAST
MULTICELLULAR MUSHROOM

4. The Characteristics of Fungi
Some fungi are internal or external parasites
A few fungi act like predators & capture prey like roundworms
Some are edible, while others are poisonous
EDIBLE
Predaceous Fungi feeding on a Nematode (roundworm)
POISONOUS

5. The Characteristics of Fungi
Produce both sexual and asexual spores
Classified by their sexual reproductive structures
Spores come in various shapes

6. The Characteristics of Fungi
Grow best in warm, moist environments
Mycology is the study of fungi
Mycologists study fungi
A fungicide is a chemical used to kill fungi
Fungicide kills leaf fungus

7. The Characteristics of Fungi
Fungi include puffballs, yeasts, mushrooms, toadstools, rusts, smuts, ringworm, and molds
The antibiotic penicillin is made by the Penicillium mold
Penicillium mold
Puffball

8. Hyphae Tubular shape ONE continuous cell
Filled with cytoplasm & nuclei
Multinucleate
Hard cell wall of chitin also in insect exoskeletons

9. Hyphae
Stolons – horizontal hyphae that connect groups of hyphae to each other
Rhizoids – rootlike parts of hyphae that anchor the fungus
STOLON
RHIZOIDS

10. Hyphae Cross-walls called SEPTA may form compartments
Septa have pores for movement of cytoplasm
Form network called mycelia that run through the thallus (body)

11. Absorptive Heterotroph
Fungi get carbon from organic sources
Tips of Hyphae release enzymes
Enzymatic breakdown of substrate
Products diffuse back into hyphae
Nucleus “directs” the digestive process
Enzymatic breakdown
Most enzyme release (and absorption) at tips
Proteins and other materials synthesized by the entire mycelium are channeled by cytoplasmic streaming to the tips of the extending hyphae.
Enzymes
Digested material is then used by the hypha

12. Modifications of hyphae
Fungi may be classified based on cell division (with or without cytokinesis)
Aseptate or coenocytic (without septa)
Septate (with septa)
NO CROSS WALLS
CROSS WALLS

13. Modifications of hyphae
HAUSTORIA – parasitic hyphae on plants & animals
Septate Hyphae
Coenocytic Hyphae

14. Hyphal growth Hyphae grow from their tips
Mycelium is an extensive, feeding web of hyphae
Mycelia are the ecologically active bodies of fungi
This wall is rigid
Only the tip wall is plastic and stretches

15. REPRODUCTION Most fungi reproduce Asexually and Sexually by spores
ASEXUAL reproduction is most common method & produces genetically identical organisms
Fungi reproduce SEXUALLY when conditions are poor & nutrients scarce

16. (Spores) SEXUAL REPRODUCTION
Used when environmental conditions are poor (lack of nutrients, space, moisture…)
No male or female fungi
Spores are an adaptation to land life
Ensure that the species will disperse to new locations
Each spore contains a reproductive cell that forms a new organism
Nonmotile
Dispersed by wind
Some fungi show dimorphism
May grow as MYCELIA or a YEAST –LIKE state (Filament at 25oC & Round at 37oC)
Dimorphic Fungi

17. - + SEXUAL REPRODUCTION
Haploid 1n hyphae from 2 mating types (+ and -) FUSE (Fertilization)
Forms a hyphae with 2 nuclei that becomes a ZYGOTE
The zygote divides to make a SPORE - +
SPORE FORMS

18. Three types of Asexual Reproduction
Fragmentation – part of the mycelium becomes separated & begins a life of its own
Budding – a small cell forms & gets pinched off as it grows to full size
Used by yeasts
Asexual spores – production of spores by a single mycelium

19. Reproduce by spores Spores may be Formed: Directly on hyphae
Inside sporangia
On Fruiting bodies
Penicillium hyphae
Fungi reproduce by releasing spores that are produced either sexually or asexually.
The output of spores from one reproductive structure is enormous, with the number reaching into the trillions.
Dispersed widely by wind or water, spores germinate to produce mycelia if they land in a moist place where there is food.
Pilobolus sporangia
Amanita fruiting body

20. ASEXUAL REPRODUCTION
Fruiting Bodies are modified hyphae that make asexual spores
An upright stalk called the Sporangiosphore supports the spore case or Sporangium

21. Types of Fruiting Bodies: Basidia Sporangia Ascus
ASEXUAL REPRODUCTION
Types of Fruiting Bodies:
Basidia
Sporangia
Ascus
Sporangia
Basidia

22. Both are composed of hyphae
Fruiting Bodies
Both are composed of hyphae
mycelium

23. Hyphal growth from spore
Germinating spore
Fungal mycelia can be huge, but they usually escape notice because they are subterranean.
One giant individual of Armillaria ostoyae in Oregon is 3.4 miles in diameter and covers 2,200 acres of forest,
It is at least 2,400 years old, and weighs hundreds of tons.
(Actually noone has seen this of this extent – but cultures have been taken from soil over that area and all isolates have been found to be the same individual)
Ten cubic centimeters of rich organic soil may have fungal hyphae with a surface area of over 300 cm2
mycelium
Mycelia have a huge surface area
More surface area aids digestion & absorption of food

24. Cladogram
Which of the following is most closely related to a mushroom (fungus)?
WHY?
Recent DNA-based studies show that fungi are more similar to animals than to plants

25. Molecular studies indicate that animals, not plants, are the closest relatives of fungi.
Both Animals and Fungi are related most closely to a group of Protists known as the choanoflagellates (collar flagellates)
Kingdom began in ocean during Precambrian (Late Proterozoic era)
More than 100,000 species of fungi are known and mycologists estimate that there are actually about 1.5 million species worldwide.
Evolution of the Fungi

26. It’s All About the Spores!
Fungi are classified by their REPRODUCTIVE STRUCTURES and SPORES
The reproductive structures are:
BASIDIA - BASIDIOMYCOTA
SPORANGIA - ZYGOSPORANGIA
ASCUS - ASCOMYCOTA

27. It’s All About the Spores!
Spores are made of:
Dehydrated cytoplasm
Protective coat
Haploid cell
Wind, animals, water, & insects spread spores
Spores germinates when they land on a moist surface (new hyphae form)

28. Classification & Phylogeny
asci
basidia
The phyla of fungi are determined by
1. motility of spores
2. nature of sexual stage
Fungi moved onto land with the plants in the Early Paleozoic
Much of the evolution of fungi was in conjunction with the evolution of plants and plant parts
For example, when roots evolved, fungi were there and helped (mycorrhizas)
When wood evolved, fungi evolved to take advantage of it
Other evolutionary changes related to animals
zygosporangia
Classification & Phylogeny
motile spores

29. Major Groups of Fungi
Within the past few years, several groups have been re-classified into the protists
Two of these groups are the slime molds and water molds

30. Classification by Nutrition
Saprobes
Decomposers
Molds, mushrooms, etc.
Parasites
Harm host
Rusts and smuts (attack plants)
Mutualists
Both benefit
Lichens
Mycorrhizas
fungi absorb nutrients from nonliving organisms.
Parasitic fungi absorb nutrients from the cells of living hosts. Saprobic
Some parasitic fungi, including some that infect humans and plants, are pathogenic.
Mutualistic fungi also absorb nutrients from a host organism, but they reciprocate with functions that benefit their partner in some way

31. Major Groups of Fungi Basidiomycota – Club Fungi
Zygomycota – Bread Molds
Chytridiomycota – Chytrids
AM Fungi - Mycorrhizas
Ascomycota – Sac Fungi
Lichens – Symbiosis (algae & Fungi)

32. ZYGOmycota

33. Rhizopus on strawberries
Zygomycota
Rhizopus on strawberries
Called the sporangium fungi
Commonly called molds
Also includes blights
Hyphae have no cross walls (aseptate)
Grow rapidly
Includes bread mold Rhizopus stolonifer
Tomato Blight
Most of the 600 zygomycote, or zygote fungi, are terrestrial, living in soil or on decaying plant and animal material.
Asexual reproduction in sporangia
One zygomycote group form mycorrhizas, mutualistic associations with the roots of plants.

34. Zygomycota
Asexual reproductive structure called sporangium atop sporangiospores make spores
Rhizoids anchor the mold & release digestive enzymes & absorb food
Stolons connect the fruiting bodies
Most of the 600 zygomycote, or zygote fungi, are terrestrial, living in soil or on decaying plant and animal material.
Asexual reproduction in sporangia
One zygomycote group form mycorrhizas, mutualistic associations with the roots of plants.

35. Zygomycota
Sexual spores are produced by conjugation when (+) hyphae and (-) hyphae fuse
Sexual spores are called ZYGOSPORES
Zygospores can endure harsh environments until conditions improve
Most of the 600 zygomycote, or zygote fungi, are terrestrial, living in soil or on decaying plant and animal material.
Asexual reproduction in sporangia
One zygomycote group form mycorrhizas, mutualistic associations with the roots of plants.
zygospore

36. Basidiomycota

37. Basidiomycota Called Club fungi Includes: Mushrooms Toadstools
Bracket & Shelf fungi
Puffballs
Stinkhorns
Rusts and smuts
Asexual spores conidia
Ecologically important on wood as decomposers and parasites
Half the mushrooms form mycorrhizas

38. USES For Basidiomycota
Some are used as food (mushrooms)
Others damage crops (rusts & smuts)
Portobello Mushrooms
Soybean Rust
Corn Smut

39. Characteristics of Club Fungi
Seldom reproduce asexually
The visible mushroom is a fruiting body
Basidiocarp (fruiting body) is made of a stalk called the stipe and a flattened cap with gills called Basidia underneath
Basidiospores are found on basidia
Annulus is a skirt-like ring around some stipes
Vegetative structures found below ground

40. Mushroom Life Cycle Hyphal fusion of haploid mycelia
mycelium and fruiting body are dikaryotic
haploid mycelium
Mushroom Life Cycle
N N N+N
Meiosis
Nuclear fusion in basidium
young basidia - the only diploid cells
Fig 31.12

41. Ascomycota

42. Characteristics Called Sac fungi
Includes Cup fungi, morels, truffles, yeasts, and mildew
May be plant parasites (Dutch elm disease and Chestnut blight)
Reproduce sexually & asexually
Ascus - sac that makes ascospores in sexual reproduction
Specialized hyphae known as Ascocarps contain the asci
Mycologists have described over 60,000 species of ascomycetes, or sac fungi.
Ascomycota tend to grow from spore to spore in one year and relate well to living plant tissues
There is diverse form in the growth and fruiting structures – yeasts to morels, many intermediate (and small)
Asexual reproduction by conidia (externally produced, not in sporangia)
Half of the Ascomycota form lichens (evolved 8 or more times in different orders) but not all lichens are Ascomycotes

43. Characteristics
Yeasts reproduce asexually by budding (buds break off to make more yeast cells)
Asexual spores called conidia form on the tips of special hyphae called conidiophores
Mycologists have described over 60,000 species of ascomycetes, or sac fungi.
Ascomycota tend to grow from spore to spore in one year and relate well to living plant tissues
There is diverse form in the growth and fruiting structures – yeasts to morels, many intermediate (and small)
Asexual reproduction by conidia (externally produced, not in sporangia)
Half of the Ascomycota form lichens (evolved 8 or more times in different orders) but not all lichens are Ascomycotes
CONIDIA

44. Conidia Formation

45. Yeasts Budding Saccharomyces
Bread and wine yeast, the budding yeast, Saccharomyces
Easily cultured. For a time, this was the most important organism for studying the molecular genetics of eukaryotes
Thus, Saccharomyces is arguably the most important organism known to humans
Candida causes diseases of humans, usually experiencing chemical imbalance or immune problems
Saccharomyces

46. Uses of Ascomycetes
Truffles and morels are good examples of edible ascomycetes
Penicillium mold makes the antibiotic penicillin.
Some ascomycetes also gives flavor to certain cheeses.
Saccharomyces cerevesiae (yeast) is used to make bread rise and to ferment beer & wine.

47. CHYTRIDIOMYCOTA

48. Chytridiomycota Called chytrids Produce motile spores
Mostly saprobes and parasites in aquatic habitats
Biodegrade and recycle nutrients
Classified in CMR as true fungi (because of their molecular relationships)
Remainder of the phyla are almost exclusively terrestrial (a few molds on wet plant material)
Chytrid that attacks Potatoes

49. MYCORRHIZA

50. Mycorrhizas Fungus associated with plant roots Mutualism between:
Fungus (nutrient & water uptake for plant)
Plant (carbohydrate for fungus)
Several kinds:
Zygomycota – hyphae invade root cells
Ascomycota & Basidiomycota – hyphae invade root but don’t penetrate cells
Extremely important ecologically
Half of the mushroom-forming fungi (basidiomycota) form mycorrhizas with trees
Some people think that the spongy tissue in roots evolved as a place where fungi could invade to form early links with plants that helped them survive the harsh life on early earth

51. Lichens

52. Lichens Mutualism between: Form a thallus (body) Fungus (structure)
Algae or cyanobacteria (provides food)
Form a thallus (body)
Foliose
Fruticose
Crustose
Thallus is a plant-like body that doesn’t have roots, stems or leaves
Thallus doesn’t look like either partner
Dual nature of thalli was not fully understood until early 1900’s
Fungus gives the name to the lichen (by agreement)
Fungus usually, but not always, an Ascomycote (in 8+ independent orders)
Algae green. If bluegreen bacteria present, lichens fix nitrogen (turn atmospheric nitrogen into amino acid nitrogen in proteins)

53. Lichen structure
The nature of lichen symbiosis is may also be described as mutual exploitation instead of mutual benefit.
Lichens live in environments where neither fungi nor algae could live alone.
While the fungi do not grow alone in the wild, some (but not all) lichen algae occur as free-living organisms.
If cultured separately, the fungi do not produce lichen compounds and the algae do not “leak” carbohydrate from their cells.
In some lichens, the fungus invades algal cells with haustoria and kills some of them, but not as fast as the algae replenish its numbers by reproduction.
Lobaria oregana prefers old-growth conifer canopies in forests with clean air.

54. Lichens as biomonitors
Thalli act like sponges
Some species more sensitive than others to pollutants
Which species are present can indicate air quality
Most resistant species can also be analyzed for pollutants
Analysis for sulfur and heavy metals in resistant species shows levels relative to levels in the environment