Review from lecture 2 - University of Saskatchewan

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Transcript Review from lecture 2 - University of Saskatchewan

Ecological roles of fungi include
• saprobic species for
– Plant resources
– Processed plant resources
• pathogenic species for hosts
Importance of fungi to soil biomass
Dung successions
• Recycle nutrients from major nutrient
resource
• Basis of a food web: fungi  invertebrates
• Succession of fungal groups: zygomycete
 ascomycete  basidiomycete
• Time to sporulation  even spore
distribution
Coprophilous fungi
• Spore dispersal mechanisms – some fungi
are dependent on being eaten for their
dispersal
• ~ 175 species of ascomycetes are largely or
exclusively found on dung
• Herbivore NOT carnivore … why?
• Some fungi are dependent on dung for
growth factors, e. g. Pilobolus (cap thrower)
Pilobolus crystallinus
• Orienting mechanism
• Positive prototropism
• Sporangium release and
attachment
• Nutritional requirements
The humungous fungus
• A. bulbosa, 15 ha in
northern Michigan
• A. ostoyae, 900 ha in
Oregon
• A single individual?
Proving the size of a single very
large subterranean fungus
• Bait soil with wooden sticks
• Collect fruiting bodies
• Grow mycelium and mate in Petri
dishes
• DNA fingerprinting
Rhizomorphs contribute to the
success of Armillaria species
• some of the largest
individuals on earth
• Rhizomorphs:
rootlike mycelial
strands
• Support spread
between localized
nutrient sources
Alan Rayner, A century of mycology
Armillaria species are tree root
pathogens
www.fungi.net/fungipics/rhizomorph.jpg
www.apsnet.org/education/IllustratedGl
ossary/PhotosN-R/rhizomorph.htm
mycorrhiza.ag.utk.edu/hawkins_rhizom1.jpg
Armillaria basidiocarps
Successions on conifer needles
Thysanophora
Lophodermium pinastri – can colonize living needles as an
endophyte; fruits after needlefall
 Fusicoccum pycnidia
attack centre of needle
Thysanophora sclerotia 
Serpula lacrymans causes “dry rot”
www.hussvamp-lab.dk/
nyhedsbreve/oktober2000.htm
www.dgfm-ev.de/www/
eng/projekte/print/pdj2004.htm
Serpula rhizomorphs and “dry rot”
‘brown rot’ fungi degrade cellulose, but not lignin
www.geo-lab.de/ schimmel.htm
www.diydoctor.org.uk/projects/
images/dryrot2.jpg
Dry rot
• Rhizomorphs transport water from damp
to dry areas
• Causes invaded wood to dry and crack
• Can penetrate but not feed on masonry
• Sensitive to warm dry environments
www.diydoctor.org.uk/projects/images/dryrot2.jpg