1. Glomeromycetes 1 Phylum Glomeromycota Endomycorrhizal fungi
symbionts that form intracellular associations (mycorrhizae) with plant roots
Endomycorrhizal fungi
extend hyphae into root cells

2. Glomeromycetes (Phylum Glomeromycota)
Coenocytic hyphae
reproduce asexually with large, multinucleate blastospores
form mycorrhizae
mutualistic symbiosis with plant roots
Which fungal phylum contain many symbiotic endomycorrhizae
a) Chytrids b) Zygomycetes c) Glomeromycetes d) Ascomycetes e) Basidiomycetes
Arbuscules are tree-like structures associated with
a) basidiomycetes b) ascomycetes c) endomycorrhizae d) ectomycorrhizae
Which of the following is not considered a “fruiting body”
a) basidiocarp b) ascocarp c) blastospore d) zygosporangiophore

3. Glomeromycetes (Phylum Glomeromycota)
Mycorrhizae*
Form associations with roots of trees and herbaceous plants
Specifically, endomycorrhizal
Grow into plant root cells
Called arbuscular mycorrhizae
Form tree-shaped structures
Which fungal phylum contain many symbiotic endomycorrhizae
a) Chytrids b) Zygomycetes c) Glomeromycetes d) Ascomycetes e) Basidiomycetes
Arbuscules are tree-like structures associated with
a) basidiomycetes b) ascomycetes c) endomycorrhizae d) ectomycorrhizae
Which of the following is not considered a “fruiting body”
a) basidiocarp b) ascocarp c) blastospore d) zygosporangiophore
* a description of ecology, not phylogeny

4. Mycorrhizal Associations
Roots supply organic nutrients for fungus
Fungus provides mineral nutrients for plant
Pine w/o mycorrhizae
Pine with mycorrhizae

5. Glomeromycetes 2 Arbuscular mycorrhizae Glomeromycetes
most common endomycorrhizae
hyphae inside root cells form branched, tree-shaped structures (arbuscules)
Glomeromycetes
have coenocytic hyphae
reproduce asexually with large, multinucleate spores (blastospores)

6. Arbuscular Mycorrhizae

7. Ascomycota – “sac fungi”
Sexual – asci
Asex. – common
Cup fungi, morels, truffles
Important plant parasites & saprobes
Yeast - Saccharomyces
Most lichens
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
A cluster of asci with spores inside

8. Ascomycetes 1 Produce asexual spores (conidia)
Produce sexual spores (ascospores) in asci
Asci line a fruiting body (ascocarp)

9. Conidia
Ascocarp
Asci

10. Ascomycete Life Cycle

11. Ascomycetes 2
Haploid mycelia of opposite mating types produce septate hyphae
Plasmogamy occurs, nuclei exchanged
Dikaryotic n + n stage occurs
hyphae form, produce asci and ascocarp

12. Ascomycetes 3 Karyogamy occurs Recombinant nuclei divide by mitosis
followed by meiosis
Recombinant nuclei divide by mitosis
produce 8 haploid nuclei that develop into ascospores
When ascospores germinate
can form new mycelia

13. Ascomycetes 4 Ascomycetes include Some ascomycetes form mycorrhizae
Fig a, p. 567
Chytrids
Zygomycetes
Glomeromycetes
Ascomycetes
Basidiomycetes
Common flagellate ancestor
Ascomycetes 4
Ascomycetes include
yeasts
cup fungi
morels
truffles
pink, brown, and blue-green molds
Some ascomycetes form mycorrhizae
others form lichens
Figure 26.13: Life cycle of a typical ascomycete.
Sexual reproduction requires haploid mycelia of different mating types. Note the dikaryotic stage and the separation of plasmogamy and karyogamy. Steps ●5 – ●8 take place within an ascus in the ascocarp.

14. ASEXUAL REPRODUCTION (by conidia)10
Germinating conidium
In asexual reproduction, hyphae produce haploid conidia that can develop into new mycelia.
ASEXUAL REPRODUCTION (by conidia)
Haploid (n)
Conidiophore
When released, ascospores germinate and form new haploid mycelia. 9
(+) mating type
Haploid mycelia of opposite mating types both produce coenocytic sexual hyphae. 1
(–) mating type 2
Plasmogamy 8
Plasmogamy occurs as hyphae of the two mating types fuse and nuclei are exchanged.
Nuclei migrate
Each nucleus becomes incorporated into an ascospore.
SEXUAL REPRODUCTION 3
HAPLOID ( n ) STAGE
Dikaryotic hyphae form and produce asci.
Mitosis produces eight haploid nuclei.
DIKARYOTIC STAGE
(n + n) 7
Mature ascus has eight haploid ascospores
Hyphae form an ascocarp.
First meiotic division 4
DIPLOID (2n) STAGE
Figure 26.13: Life cycle of a typical ascomycete.
Sexual reproduction requires haploid mycelia of different mating types. Note the dikaryotic stage and the separation of plasmogamy and karyogamy. Steps ●5 – ●8 take place within an ascus in the ascocarp.
Developing ascus
with
n + n
nuclei
Second meiotic division
Nuclei fuse
Zygote
Meiosis
Ascocarp 6
Meiosis occurs, forming four haploid nuclei.
Karyogamy 5
Mycelium
Karyogamy occurs in each ascus. Two haploid nuclei fuse, forming a diploid zygote nucleus.
Fig b, p. 567

15. Fungal Evolution Chytridiomycetes Zygomycetes Glomeromycetes
Ascomycetes
Basidiomycetes

16. Ascomycetes (Phylum Ascomycota)
Ascomycetes include
yeasts
cup fungi
morels
truffles
pink, brown, and blue-green molds
Yeasts, morels, truffles, cup fungi, and blue-green molds are part of the
a) Chytrids b) Zygomycetes c) Glomeromycetes d) Ascomycetes e) Basidiomycetes

17. Ascocarp - “fruiting body”
Ascomycetes
Have septate hyphae
Produce coenocytic sexual hyphae
Following plasmogamy, dikaryotic (n + n) hyphae form in an ascocarp* (fruiting body)
Ascocarp - “fruiting body”
*made of monokaryotic hyphae

18. Ascomycetes Karyogamy occurs at tips of hyphae (asci)
followed by meiosis and mitosis
produces 8 haploid nuclei that develop into ascospores
Asci - form sexual spores in groups of 8
Sexual spores that are formed in groups of eight are associated with the
a) Ascomycetes b) Basidomycetes c) Chytrids d) Glomeromycetes e) Zygomycetes

19. Ascomycetes (Phylum Ascomycota)
Asexual reproduction
involves formation of colored spores (conidia) at the tips of specialized hyphae (conidiophores)
Penicillium conidiophores

20. –Johnny Appleseed

21. Fungal Evolution Chytridiomycetes Zygomycetes Glomeromycetes
Ascomycetes
Basidiomycetes

22. Basidiomycetes Phylum Basidiomycota
include the largest and most familiar of the fungi
mushrooms
bracket fungi
puffballs
rusts
smuts
A “toadstool” or mushroom is most likely the fruiting body of this group
a) Basidiomycetes b) Zygomycetes c) Ascomycetes d) all these e) none of these
Mushrooms, puffballs, bracket fungi, rusts, and smuts are part of which phylum?
a) Chytrids b) Zygomycetes c) Glomeromycetes d) Ascomycetes e) Basidiomycetes

23. Basidiomycetes Septate hyphae
a secondary mycelium forms after plasmogamy
dikaryotic hyphae
compact buttons grow into mushrooms (fruiting bodies) called basidiocarps
A “toadstool” or mushroom is most likely the fruiting body of this group
a) Basidiomycetes b) Zygomycetes c) Ascomycetes d) all these e) none of these
Sexual spores that are formed in groups of four are associated with the
a) Ascomycetes b) Basidomycetes c) Chytrids d) Glomeromycetes e) Zygomycetes

24. Basidiomycetes (Phylum Basidiomycota)
Karyogamy takes place within young basidia on the gills of the mushroom
each basidium produces 4 basidiospores
A “toadstool” or mushroom is most likely the fruiting body of this group
a) Basidiomycetes b) Zygomycetes c) Ascomycetes d) all these e) none of these
Sexual spores that are formed in groups of four are associated with the
a) Ascomycetes b) Basidomycetes c) Chytrids d) Glomeromycetes e) Zygomycetes

25. Basidiospores released1 2 7
Plasmogamy 3
HAPLOID (n) STAGE
Second meiotic division
DIKARYOTIC STAGE
(n + n)
“Type a quote here.”
First meiotic division 4
DIPLOID (2n) STAGE
Figure 29.17: Life cycle of a typical basidiomycete.
Note the dikaryotic stage and the separation of plasmogamy and karyogamy. Steps 5 and 6 take place within the basidia of the basidiocarp. Asexual reproduction is uncommon in this group.
1 Basidiospores germinate and form primary mycelia.
2 Plasmogamy of primary mycelia occurs with the fusion of two ( n ) hyphae of different mating types.
3 Fast-growing secondary mycelium is produced, composed of dikaryotic ( n + n ) hyphae.
4 Basidiocarps periodically develop from secondary mycelium.
5 Basidia form along gills of basidiocarps. In each basidium karyogamy occurs, producing a zygote nucleus.
6 Meoisis occurs, producing four haploid nuclei that become basidiospores.
7 Basidiospores forming
–Johnny Appleseed 6
Meiosis
Zygote
Karyogamy
Gills
Basidiocarp 5
Secondary mycelium

26. Basidiomycetes
Many basidiomycetes produce “fairy rings” in lawns and forests
The circle widens as the fungi grow outward

27. “Type a quote here.” Cells of root cortex Root epidermis Soil Vesicle
Root hair
“Type a quote here.”
Arbuscule
Spore
Figure 29.11: Arbuscular mycorrhizae.
This mycelium has grown into a plant root. Its hyphae branch between the cells of the root. Hyphae have penetrated through the cell walls of two root cells and have branched extensively to form arbuscules. The tip of one hypha between root cells has enlarged and serves as a vesicle that stores food. The tip of a hypha in the soil has enlarged, forming a spore. The spaces between the root cells have been magnified for clarity.
–Johnny Appleseed
Cortex cell
Hypha of fungus

28. Basidiomycota – “club fungi”
Sex – basidia
Asex – rare
Long-lived dikaryotic mycelia
Rusts & smuts – primitive plant parasites
Mushrooms, polypores, puffballs
Enzymes decompose wood
Mycorrhizas
Asexual spores conidia
Ecologically important on wood as decomposers and parasites
Half the mushrooms form mycorrhizas
SEM of basidia and spores

29. Basidiomycetes 1 Produce sexual spores (basidiospores) Basidia develop
on outside of basidium
Basidia develop
on surface of gills in mushrooms
a type of basidiocarp (fruiting body)
Hyphae in this phylum have septa

30. Basidiomycete Fruiting Bodies

31. Basidiomycetes 2 Plasmogamy occurs Dikaryotic secondary mycelium forms
fusion of 2 hyphae of different mating types
Dikaryotic secondary mycelium forms
Basidiocarp develops
basidia form

32. Basidiomycetes 3 Karyogamy occurs Meiosis produces 4 haploid nuclei
producing diploid zygote nucleus
Meiosis produces 4 haploid nuclei
become basidiospores
When basidiospores germinate
form haploid primary mycelia

33. Plasmogamy of haploid mycelia
mycelium and fruiting body are dikaryotic
Plasmogamy of haploid mycelia
haploid mycelium
Mushroom Life Cycle
N N N+N
Meiosis
Karyogamy in basidium
young basidia - the only diploid cells

35. Basidiospore Basidium 5 µm Fig. 26-16, p. 570
Figure 26.16: SEM of a basidium.
Each basidium produces four basidiospores.
5 µm
Fig , p. 570

36. Basidiomycetes 4 Basidiomycetes include mushrooms puffballs
bracket fungi
rusts
smuts

37. Yeasts Single celled fungi Adapted to liquids Plant saps Water films
Moist animal tissues
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
Candida
Saccharomyces

38. Fungal Ecology Saprobes Parasites Mutualists Decomposers
Mostly of plants, some animals
Parasites
Harm host
Mostly on plants, some animals
Mutualists
Lichens
Mycorrhizas
Others
Saprobic fungi absorb nutrients from nonliving organisms.
Parasitic fungi absorb nutrients from the cells of living hosts.
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

39. Importance of Fungi
Decomposers and nutrient recyclers

40. Importance of Fungi
Mutualists: organisms that are associated with each other to their mutual benefit
Most trees and prairie plants have fungi called mycorrhizae associated with their roots.
help the plants gather nutrients

42. Beatrix Potter - Mycologist

43. Beatrix Potter
Was the first person in Britain to speculate in a scientific paper that lichens are symbiotic life forms
She conducted experiments in her kitchen, and recorded in detail her observations of algal and fungal properties.

44. Lichens Dual organisms Composed of a fungus and an alga
Appear to also have a third yeast partner
Fungus gathers water, minerals, and provides a home for the algae
Algae provides sugars for the fungus

45. Commercial Uses for Fungi
Beer and wine are produced by fermentation using single celled fungi called yeasts
Produce alcohol and carbon dioxide
Carbon dioxide from fermentation by yeast causes bread dough to rise
Foods
Mushrooms, corn smut (a favorite in Mexico)

46. Corn smut
Chanterelles

47. Problem Fungi Some fungi are parasites of plants and animals
Athletes foot
Vaginal yeast infections, thrush
Rust on wheat plants
Ergot grows on rye seeds - produces LSD
May have been the culprit behind the accusations of witchcraft in 1620 Salem
Mildew in your shower (not a disease producer - just gross!)

49. Hyphae are the threadlike fibers that make up the mycelium.
Hyphae are composed of partially separated cells-like compartments
Cellular components can move between cells of hyphae.
Most of the mycelium is hidden in the substrate (the ground, piece of fruit, etc). Reproductive structures are visible above ground
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