1. Basidiomycotina (2) Chromistan Fungi Eumycotan Fungi. Ascomycotina
1. Chytridiomycota
2. Zygomycota
3. Dikaryomycota
Ascomycotina
Basidiomycotina
phyla sub-phyla

2. Basidiomycotina - main features (cf. Ascomycetes)
sexual spores (basidiospores) outside basidium
complex septal pores
extended dikaryophase (most hyphae)
multi-layered cell walls
clamp connections
molecular differences from ascomycetes anamorphs occur but are less important

3. Basidiomycotina Holobasidiomycetes (Mushrooms) B. Basidia subdivided.
A. Basidia not subdivided)
Holobasidiomycetes (Mushrooms)
Hymenomycetes - forcible discharge of spores
Gasteromycetes - not forcible
B. Basidia subdivided.
Phragmobasidiomycetes - jelly fungi (gelatinous fruit bodies)
Teliomycetes
- rust and smut pathogens - no fruit bodies

4. Not all mushrooms have gills.
The ‘Boletes’ have pores instead.

5. Some important Gasteromycetes
Lycoperdales - puffballs, earthstars
Sclerodermatales - earthballs
spores borne in large masses (gleba) often covered with thin skin
Nidulariales - birds-nest fungi
Phallales - stinkhorns
foul smell attracts flies - disperse spores

6. Sclerodermatales
Pisolithus tinctorius,
an important ectomycorrhizal fungus.
gleba

7. Puffballs - can be several feet in diameter
Gleba - masses of spores inside

8. Gleba divided up into several peridioles (‘eggs’)- splashed out of cup by rain - attaches at new site and forms basidia
Nidulariales - Birds’ nest fungi

9. Spore dispersal in Birds Nest Fungi (Cyathus)

10. Phallales - stinkhorns
Mutinus sp.
Phallus sp.

13. Basidiomycotina Phragmobasidiomycetes
Basidia are subdivided
Jelly like fruit bodies, sometimes blobs, sometimes ‘ear-shaped’
some are mycoparasites, none of economic importance

14. Phragmobasidiomycetes - Jelly Fungi
Photo - Dr. Greg Thorn
Phragmobasidiomycetes - Jelly Fungi

15. Basidiomycotina Teliomycetes - Rusts and Smuts
Basidia are subdivided - 4 cells
No fruit bodies - instead basidia formed on overwintering diploid spores (teliospores)
simple septal pores
Many important pathogens of crops and other plants

16. Teliomycetes - Rusts and Smuts
Uredinales - Rust fungi
obligate pathogens with complex cycles - often alternate hosts for anamorph/teleomorph
localized infection
special sex organs (spermatogonia/receptive hyphae)
Ustilaginales - smut and bunt fungi
facultative pathogens - no alternate hosts - have yeast like anamorph
systemic but often form spores just in flowers
no spermatogonia - any two cells can fuse

17. Uredinales - Rust fungi
Some rusts such as Black Stem rust (Puccinia graminis) have:-
1. 5 different spore types (macrocyclic)
2. alternate hosts (heteroecious) cycles between Wheat & Barberry .
3. sub-species & physiologic races which specialize on different grass sp. and varieties.
Others have fewer types of spore (microcyclic) and/or only one host (autoecious)

18. Puccinia graminis - black stem rust.

19. 3 Spermagonia forming
innumerable tiny haploid spermatia which ooze out in a sweet-smelling nectar. Insects are attracted by the nectar, and walk or fly from one spermagonium to another, transferring spermatia of each mating type to receptive hyphae of the other type. This process initiates the dikaryophase. The dikaryotization spreads to the lower surface of the barberry leaf and produces cup-like structures called aecia - two are shown in this section.
Aeciospores (n + n)

20. The flower-like aecia burst through the host epidermis, and liberate dikaryotic aeciospores - but these spores can't infect the barberry - they must infect a wheat plant where they soon form uredinia (n+n)
Uredinia of Puccinia sp. growing on Ribes.
Red pustules give rust fungi their name.

21. The uredinia on wheat produce first masses of urediniospores (n+n) which rapidly spread the infection in wheat - producing more uredinia
Later thick walled overwintering teliospores (2n) are produced - spores which germinate to give basidiospores (n) which infect barberry to begin cycle again.

22. In rusts the teliospore replaces the fruit body - germinates to produce a compartmented basidium which then produces the 4 basidiospores (often forcibly discharged)

23. Some other important rusts
Teliomycetes - Uredinales - telial horns of Gymnosporangium on juniper (Juniperus).
Aecial stage of Cronartium fusiforme - blister rust on Pinus (left).
Uredinia and teliospores on Currant (right)
Hemilaea vastatrix - coffee rust - wiped out coffee in Ceylon - hence now grow tea

24. Ustilaginales - Smut + bunt fungi
Form masses of dark diploid thick-walled spores (teliospores) in flowers or fruit, leaves or stems
Teliospores produce 3-4 celled basidium which buds off basidiospores (not forcibly expelled) - which bud off more sporidia
Can grow saprobically as yeast-like haploid sporidia; fuse in/on host - grow systemically as dikaryotic hyphae.
Several important pathogenic species e.g corn smut (Ustilago maydis); loose smut of barley(Ustilago nuda), bunt of wheat (Tilletia caries) and onion smut (Urocystis cepulae)

25. Ustilago maydis - corn smut. spores often replace entire cob

26. Loose smut, a disease of barley caused by Ustilago nuda
Loose smut, a disease of barley caused by Ustilago nuda. Spores replace grains
Ustilago violacea - anther smut. Systemic infection but forms spores only in anthers (replaces pollen)
causes sex change in plant

28. Sporidia of U. violacea
Fimbriae - very long protein-RNA fibrils on surface of cells (only 7nm wide)

29. Tilletia (Stinking Smut)

30. Follow-up to lecture Chap 5, text, Web and CD.
know main features of Basidiomycetes and how to distinguish from other groups.
Important economic species
key life cycles -
typical mushroom, rust, smut life cycles
review terms -
teliospore, sporidia, 5 spore types of rusts, heteroecious, autoecious, macrocyclic, microcyclic.