Transcript Introduction to Mycology - MIKROBIOLOGI FARMASI INDONESIA

Introduction to Mycology
General Mycology Lecture 1
Pl P 421/521
What is a fungus?
• A eukaryotic, heterotrophic organism
devoid of chlorophyll that obtains its
nutrients by absorption, and reproduces
by spores.
• The primary carbohydrate storage product
of fungi is glycogen.
• Most fungi have a thallus composed of
hyphae (sing. hypha) that elongate by tip
growth
Fungal hyphae form a network
called a mycelium (pl. mycelia)
• Carl Linnaeus (1707-1778)
the “Father of Taxonomy”
– “ Minerals exist; plants exist
and live; animals exist, live
and sense.”
– Plants without obvious
sexual organs were
classified in Class
Cryptogamia (lichens, fungi,
mosses, ferns)
• Fungi are primitive plants
under this classification of
organisms.
R. H. Whittaker’s 1969 Classification
Modern Classification
• At least 7 kingdoms are now recognized:
– Eubacteria, Archaebacteria, Animalia,
Plantae, Eumycota, Stramenopila
(Chromista), Protoctista (Protozoa, Protista)
Fungi versus fungi
• “fungus” is used inclusively for a
heterogenous group of organisms that
have traditionally been studied by
mycologists
• “Fungi” refers to the organisms in the
Kingdom Fungi, the true fungi, also
called the “Eumycota”
Kingdom Fungi
Phyla: Chytridiomycota
Zygomycota
Glomeromycota
Ascomycota (inc.Deuteromycetes)
Basidiomycota
Glomeromycota
Kingdom Stramenopila (Chromista)
Phyla: Oomycota
Hyphochytriomycota
Labyrinthulomycota
Protists (Protoctists)
Phyla: Plasmodiophoromycota
Dictyosteliomycota
Acrasiomycota
Myxomycota
Hierarchical Classification
Kingdom Fungi
Phylum Basidiomycota
Class Basidiomycetes
Order Agaricales
Family Agaricaceae
Genus Agaricus
Species:
Agaricus campestris L.
Agaricus campestris L.
• Agaricus is the genus
• campestris is the specific epithet
• The genus + species is the Latin binomial; note
that the genus and species are in italics (or
underlined), the genus is capitalized and the
species epithet is in lower case
• L. stands for Linnaeus, the authority
• Agaricus campestris is the type species of the
genus
Agaricus bisporus (Lange) Imbach
• Lange first described this fungus as Coprinus
bisporus
• Imbach later transferred the species to Agaricus
Nomenclature
• Nomenclature: the “allocation of scientific
names to the units a systematist considers to
merit formal recognition.” (Hawksworth et al.,
1995. The Dictionary of the Fungi).
• The nomenclature of fungi is governed by the
International Code for Botanical Nomenclature,
as adopted by the International Botanical
Congress.
Typological Species Concept
• "Species are as many as were created in the
beginning by the Infinite." (Linnaeus, 1758)
• Each species represented by a type specimen,
designated in the original description and
deposited in a recognized collection (eg.,
herbarium)
• The name is tied to the type specimen
• The type specimen is not necessarily typical of
the entire species!
How are fungi named?
• To determine the correct name for a taxon,
certain steps must be followed, including:
– Effective publication
– Valid publication
• Description or diagnosis in Latin
• Clear indication of rank
• Designated type
How many species of fungi
exist?
80,000 species of fungi described
1,700 new species described
each year
Estimating the number of fungal
species
• Hawksworth, D. L. (1991). The fungal
dimension of biodiversity: magnitude,
significance, and conservation.
Mycological Research 95: 641-655
• Hawksworth, D.L. (2001) The magnitude
of fungal diversity: the 1.5 million species
estimate revisited. Mycological Research
105 (12): 1422-1432.
Fungi are ancient
• Major fungal lineages are ancient, perhaps
emerging one billion years ago
• Fungi were present before the emergence
of animals and vascular plants
Mass extinction at K-T boundary;
fungal ‘spike’
Increasing diversity of angiosperms,
mammals, birds
Gymnosperms dominant, evolution of
angiosperms; first birds
Gymnosperms become dominant, first
dinosaurs, first mammals
Mass extinction of ~95% of all species;
fungal ‘spike’
Origin of insects, ferns, seed plants
Earliest terrestrial vascular plants
marine animals diversify; first
appearance of most animal
phyla; diverse algae
Modified from Blackwell, 2001
Associations
• Fungi form symbiotic
relationships with a
number of organisms:
– Lichens
– Mycorrhizas
– Endophytes
Decomposers
• As saprotrophs,
particularly as
decomposers, fungi
are essential
components of the
carbon cycle and are
among the few
organisms that can
break down lignin
Pathogens
• Fungi are important
as pathogens of
animals and plants.
– Over 70% of all plant
diseases are caused
by fungi