FUNGIFUNGI
Dr. Dr. LeenaLeena S. S. BarhateBarhate
Department of MicrobiologyDepartment of Microbiology
M.J.CollegeM.J.College,,
JalgaonJalgaon..
Fungi In The Scheme Of LifeFungi In The Scheme Of Life
PlantaeFungi
Monera
Animalia
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... .. ..
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Protista
Kingdom
Kingdom
Photosynthetic
Nutrient
uptake by
absorption
Nutrient uptake
by ingestion
Whittaker’s Five –
Kingdom Concept
MycologyMycology
Gr. Gr. MykesMykes = mushroom or fungus= mushroom or fungus
LogusLogus = discourse= discourse
AlexopoulousAlexopoulous and and MimsmMimsm, the Italian , the Italian
botanist Pier ‘ Antonia botanist Pier ‘ Antonia MicheliMicheli called called
founder of mycologyfounder of mycology
What are fungi?What are fungi?
Fungi (fungus, Mushroom) are Fungi (fungus, Mushroom) are
achlorophyllusachlorophyllus, chemoorganotrophic, chemoorganotrophic
heterotrophic (Saprophytic, parasitic, heterotrophic (Saprophytic, parasitic,
symbiotic or symbiotic or hyperparasitichyperparasitic), eukaryotic and ), eukaryotic and
sporespore--bearing organisms bearing organisms
surrounded by a well defined cell wall made surrounded by a well defined cell wall made
up of chitin with or without fungal cellulose, up of chitin with or without fungal cellulose,
along with many other complex organic along with many other complex organic
molecules.molecules.
Distribution and HabitatDistribution and Habitat
The fungi are cosmopolitan in distribution The fungi are cosmopolitan in distribution
Diverse habitatDiverse habitat
Majority Majority –– terrestrialterrestrial
Few Few –– aquaticaquatic
Most are saprophyticMost are saprophytic
ParasiticallyParasitically
FungiFungi--3. large diverse group3. large diverse group
rustsrusts aquatic fungiaquatic fungi mushroomsmushrooms
Yeast Characteristics
solitary, unicellular
reproduction via budding
rounded shape
moist & mucoid colonies
Mould Characteristics
filamentous hyphae
hyphal formation
tips may be rounded
(conidia/spores)
Figure 1. Typical Yeast
Figure 2. Typical mould
Dimorphic fungiDimorphic fungi
Exist in two formsExist in two forms
Mostly pathogenicMostly pathogenic
Have unicellular and Have unicellular and yeastlikeyeastlike form in host form in host
but but saprophyticallysaprophytically in soil or laboratoryin soil or laboratory
mediummedium
Opposite dimorphic phenomenon occurs in Opposite dimorphic phenomenon occurs in
some plant pathogens. (some plant pathogens. (TaphrinaTaphrina or in or in
Smuts)Smuts)
Fungal CharacteristicsFungal Characteristics EukaryoticEukaryotic
MulticellularMulticellular
HeterotrophicHeterotrophic
Absorb nutrients Absorb nutrients -- may be saprobes (absorb may be saprobes (absorb from dead material), parasites, or mutualistic from dead material), parasites, or mutualistic symbionts (with algae make lichen).symbionts (with algae make lichen).
Secrete powerful hydrolytic enzymesSecrete powerful hydrolytic enzymes
Cell walls contain chitin, an amino sugar Cell walls contain chitin, an amino sugar polysaccharide also found in arthropod polysaccharide also found in arthropod exoskeletonsexoskeletons
Lack flagellaLack flagella
Vegetative body consists of Vegetative body consists of
mycelia mycelia made up of networks of made up of networks of
hyphaehyphae
Hyphae Hyphae -- Long treads of cells Long treads of cells
designed to maximize surface area designed to maximize surface area
and also transport nutrientsand also transport nutrients
FungusFungus--like like protistsprotists::
––Lack this body structureLack this body structure
––Lack cell walls of chitinLack cell walls of chitin
The Body Plan of FungiThe Body Plan of Fungi
HyphaeHyphae Hyphae are designed to increase the surface Hyphae are designed to increase the surface
area of fungi and thus facilitate absorptionarea of fungi and thus facilitate absorption
May grow fast, up to 1 km per day, as they May grow fast, up to 1 km per day, as they
spread throughout a food sourcespread throughout a food source
Modifications of hyphae into Modifications of hyphae into specialisedspecialised
structuresstructures RhizoidsRhizoids
–– RhizopusRhizopus
AppresoriaAppresoria
–– Produced by parasites Produced by parasites
–– EgEg. Rusts and powdery mildews. Rusts and powdery mildews
HaustoriaHaustoria ((HausterHauster = drinker)= drinker)
HyphalHyphal traps traps egeg. . DactylellaDactylella, , ArthrobotryaArthrobotrya
PlectenchymaPlectenchyma
–– ProsenchymaProsenchyma
–– pseudoparenchymapseudoparenchyma
HaustoriaHaustoria -- Specialized structures budding Specialized structures budding
off hyphae of parasitic fungi which penetrate off hyphae of parasitic fungi which penetrate
host cells to absorb nutrientshost cells to absorb nutrients
Some fungiSome fungi
–– Have hyphae divided into cells by septa, with Have hyphae divided into cells by septa, with
pores allowing cellpores allowing cell--toto--cell movement of cell movement of
materialsmaterials
Coenocytic fungiCoenocytic fungi
–– Lack septaLack septaNuclei
Cell wall
Septu
m
Pore
(a) Septate hypha (b) Coenocytic hypha
Cell wall
Nuclei
Type of Septum
in fungi
Type of septa in fungiType of septa in fungi
SieveSieve-- like septum:like septum:
–– Uniform distributed pores throughout the area of Uniform distributed pores throughout the area of
septumseptum
–– EgEg GeotrichumGeotrichum
Simple pore septum:Simple pore septum:
–– Found in Found in ascomyceteascomycete fungi.fungi.
–– Single, simple central pore.Single, simple central pore.
DoliporeDolipore septum:septum:
–– Cell wall abutting the pore expandsCell wall abutting the pore expands
–– Central pore is plugged by the membrane of ER Central pore is plugged by the membrane of ER
called called parenthosomeparenthosome
–– Found in Found in basidiomycetousbasidiomycetous fungifungi
Bordered pit typeBordered pit type--septum:septum:
–– Pore is surrounded by an over arching Pore is surrounded by an over arching
bifurcation of the bifurcation of the septalseptal margin.margin.
–– Look like a bordered pit of a tracheid of Look like a bordered pit of a tracheid of pinuspinus
–– Found in Found in mucoralesmucorales and and trichomycetestrichomycetes..
• reproduction mainly by spores (both sexual and asexual)
• spores somewhat resistant to harsh environmental conditions
• spore germination mainly upon exposure to water
• sexual spore (perfect stage)terms vary
• asexual spores = conidia, formed on conidiophores
• Asexual- (imperfect stage)
• spores formed by mitosis
• some fungi exhibit only asexual reproduction (imperfect fungi)
Nutrition and Growth Nutrition and Growth
requirementsrequirements
Devoid of chlorophyllDevoid of chlorophyll
HeterotrophicHeterotrophic
Type based on nutrientType based on nutrient
Obligated saprophytes Obligated saprophytes egeg. . AgaricusAgaricus
Facultative saprophytes or parasites Facultative saprophytes or parasites egeg. .
AlternariaAlternaria , , PythiumPythium
Obligate parasites Obligate parasites egeg. . AlbugoAlbugo, , PucciniaPuccinia
SymbiontsSymbionts (Lichens and (Lichens and mycorrhizaemycorrhizae))