Lecture 4 Flashcards
What are the two main types of mycorrhizas
Endomycorrhiza
Ectomycorrhiza
What is an Endomycorrhiza
- most common; occurring 80% of all vascular plants
- fungal component is a glomeromycete
specialized structures (vesicles and arbuscules) - structure penetrates cortical cells of the plant root (endo)
- association not very specific (200 species of glomeromycete involved)
What are two examples of Endomycorrhizas
Gigaspora
Glomus
- arbuscules within cortical cells
What is an Ectomycorrhiza
- most formed by basidiomycete
- less often formed with ascomycetes
- formed in temperate regions with certain tree and shrub species (beech & tea tree)
- fungus does not penetrate the root cells but forms a net-like structure (Hartig net) surrounding the root and between the cortical cells
- specific interaction between plant and fungus
What are the characteristics of Ascomycota
- septate hyphae (perforated with pore);or single cells in yeasts
- conidiophores
- conidia
- asci
- naked asci
- hymenium
- ascomata (ascocarp)
What is a conidiophore
- has a soft wall at the tip
- pressure causes the wall to inflate; forming a bud
- crosswall forms at the base of the bud to release the spore
- regenerate the conidiophore inflatable tip
- repetition leads to a chain of spores
- produces conidia at tip
What is the main way of dispersal of ascomycetes
conidia
- asexual reproduction
What are ascospores
sexual spores produced in ascus
What is an ascus
(plural asci)
sacs produced in a hymenium
What is a hymenium
fertile layer of asci found within an ascocarp(singular)
What is an ascocarp/ascoma
ascomata (pl)
sexual fruiting body
How many ascospores are in an ascus
8
What are the three form types of Ascomata
- ) Cleistothecium
- ) Perithecium
- ) Apothecium
What does a Cleistothecium look like
closed
What does a Perithecium look like
flask + pore
What does a Apothecium look like
cup
Where is ascomata usually found
embedded in host tissue or on
What are two examples of ascomyctes
Botrytis cinerea
Venturia inequalis
true or false; Botrytis cinerea is an anamorph classfication
true
What is the teleomorph term for Botrytis cinerea
Botryotinia fuckeliana (rare)
What is the anamorph word of apple scab fungus
Spilocaea pomi
What is the teleomorph word for apple scab fungus
Venturia inequalis
What causes Peach leaf curl fungus
Taphrina deformans
What is formed on the surface of a peach leaf when infected with Peach leaf curl fungus
naked asci forming on hymenium (no ascomata)
What does naked asci mean
formation of asci on hymenium without an ascoma/ascomata
What is Claviceps purpurea or Ergot fungus
- endophyte (mutualistic symbiont)
- produces ergots on rye flowerheads
- causes ergotism = human disease
- can be used to make Ergotamine (migraines)
What are the symptoms of ergotism
gangrene
nervous spasms
psychotic delusions
convulsions (Salem witches)
Why does Claviceps purpurea cause ergotism
the ergots on the rye flowerhead produce ergot alkaloids
What are the characteristics of Ergots
- can withstand winter
- hard
- black structure
What is Awheto
fungus
Cordyceps robertsii
true or false; Awheto is an insect parasite and charcoal pigment for ta moko
true
What are examples of edible ascomycetes
morels
truffles (ectomycorrhizal)
What causes thrush
Candida albicans
- problematic when low immunity
- opportunistic pathogen
What is an example of ascomycete yeast
Saccharomyces cereviseae
What are lichens
- mutualistic symbiotic associations
- ascomycetes and photosynthetic green algae and/or cyanobacteria
- occupy harsh environments
- environmental pollution indicators (lots of lichens means clean air)
What is a lichen comprised of
Algae (or cyanobacterium) + fungus
What is the significance of cyanobacterium in lichens
allows nitrogen fixation
What are industrially important anamorphic fungi (asexual) ; genus
Penicillium and Aspergillus
What are examples of the roles of Peniciullium in the industry
Penicillium roquefortii - blue cheese
Penicillium camemberti - camembert and brie
What are the roles of Aspergillus in the industry
Aspergillus oryzae and A. soyae
- soybean fermentation
A. oryzae
- sake
Aspergillus
- large scale production of citric acid for food industry
Define ascogonium
female gametangium of ascomycetes
Define trichogyne
In red algae and certain ascomycetes and Basidiomycota, a receptive protuberance of the female gametangium for the conveyance of spermatia
Define crozier
A hooked tip formed by the apical cell of an ascogenous hypha that allows paired nuclei to divide simultaneously, one in the hypha and the other in the hook
Define ascogenous hyphae
Hyphae containing paired haploid male and female nuclei; they develop to form an ascogonium and eventually give rise to asci
