Myco = Fungus
logy = Study
‫إعــــــداد الطــــــــــالب‬
‫أحمــد سمير فتحي‬
‫محمد ماهر محمود‬
‫أحمد محمــد نجيب‬
‫سوزان عبدالحكم‬
‫إيمان ناصرأحمـد‬
‫أسماء عبــــــادة‬
‫محمد إبراهيم المهدي‬
‫تحت إشراف‬
‫الدكتور‪ /‬عبدالدايم أبوالفتوح شريف‬
‫قسم النبات – كلية العلوم – جامعة المنصورة‬
‫)‪(2008 – 2009‬‬
Mycology : is a branch of science which
concentrate on studying fungi.
1. General Characters
2. Nutrition
3. Economic Importance
4. Reproduction
5. Classification
1- General Characters
•Eukaryotic Organisms (i.e true nucleus)
•Non-Vascular Organisms
•Non-motile except few fungi
•Vegetative body may be:
unicellular
Filamentous
Septated
Non-Septated
•Like plants, have alternation of generation
•cell wall similar in structure of plant but
differ in chemical composition
Plant C.W.
Cellulose + lignin
Fungi C.W.
Chitin
•Fungi are Heterotrophic organisms
•Growth by apical elongation of hyphal tip
•Food stored as glycogen but plant as starch
•Cell membrane
in animal cholesterol
in Fungi ergosterol
•Fungi produce exoenzymes to digest food
then ingest it
•Reproductive Structures are differentiated
from somatic structures
•Cytoplasmic ultrastructures similar to
plant cells , but differ in kinds or organelles
•Most fungi have very small nuclei , with little
repetative DNA
•Reproduction
Sexual
Asexual
Vegetative
2- Nutrition in fungi
Saprophytes
Parasites
Symbiotic
•Saprophytes : 1- use non - living organic
materials
2- important in recycling C,N
and essential mineral
nutrients
•Parasites : 1- use organic materials from
living organisms , causing
diseases to them
2- they have a wide range of
hosts as diatoms , fungi ,
plants ,animals , human .
•Symbiotic : 1- fungi that have a beneficial
symbiotic relationship with
other living organisms
Ex :
Mycorrhizae
Lichens
Commensalism
Mycorrhizae
It is associations of fungi with plants roots
•Types of Mycorrhizae :
Ectomycorrhizae
•Fungus form a sheath
around the root with hyphal
grow through the soil which
increase the surface area
•Fungus penetrate between
cells of cortex
•Ex. Basidiomycota and
Ascomycota
Endomycorrhizae
•Fungus doesn’t form
sheath around the roots
•Fungus penetrate the
cells of cortex without
penetrating the cell
membrane
•Ex. Zygomycota
Lichens
•Symbiotic relation between fungus and algae
Most are Ascomycota ,few are Basidiomycota
•Lichens uses
1. Lichens break down rocks into soil
2. Food source for some animals
3. Source for dyes , tweed
Commensalism
•One organism uses another to get better position
•No physiological interaction
•Maybe for photosynthesis or reproductive advantages
3- Economic Importance
Useful
•Yeast to
bread & brew
•Antibiotics
penicillin
•Steroids and Hormons
•Stinky Cheeses
•Source of organic compost
•Source of food
Harmful
•Cause human,animal, plant
disease directly or their toxins
•Cause rot of food
•Can destroy manufactured
good
•Experimental importance as:
•Easily cultured, take little space, multiply rapidly, short life cycle
•Study metabolic pathways
•Study growth, development, differentiation
•Microbial assay of vitamins and amino acids
•Study mechanism of cell division and development
4- Reproduction
•Types of reproduction :
Sexual
Asexual
vegetative
a. Sexual:
- Involve the union of two compatible nuclei with
a subsequent meiotic division
- All sexual fungal life cycles consists of :
plasmogamy
Cell fusion
karyogamy
Nuclear fusion
meiosis
2N
reduced to
1N
Meiosis
•1n
•2n
Haploid number of chromosomes
Diploid number of chromosomes
•The two fusing gametes may be:
1. Morphologically the same, they are called
isogametes and the process of fertilization
is called isogamous
2. Differ in size and structure, they are called
heterogametes and the process of fertilization
is called heterogamous
Anisogamy
The fussing gametes
are morphologically
the same but differ
in size
oogamy
.Differ in everything
.As between antheridium and
oogonium or ascogonium
antheridium
•Methods of plasmogamy:
Gametangial
contact
Gametangial
copulation
•Gametangial contact:
Spermatization
oogonium
antheridium
•The male and female gametangia
come into contact with each other,
and the male nuclei from male
antheridium are transferred into the
egg
female oogonium either; through
a pore at the point of their contact or through a tube
called fertilization tube arise from antheridium to
oogonium, then plasmogamy & karyogamy occur
inside the oogonium.
•Gametangial copulation:
•Fusion occurs between the entire content of the two
gametangia by one of the following ways:
a. Contents of one gametangium is transferred to
the other through a pore at the point of their
contact
suspensor
b. The content of the two
+
gametangia fuse by the
dissolution of their contact
walls, leading to the formation
of a common cell, in which the content of the two
gametangia mix
•Spermatization
spermatia
•Occurs by the transfer of
spermatia (unicellular – non
motile male cells) by wind,
water or insects to a special
receptive hyphae on the
Receptive hyphae
female gametangium
1. The sex organs are called gametangia which may be
differentiated into antheridium & oogonium and
produce different sex gametes
2. Some fungi are: homothalic (single mycelium
reproduce sexually), others are heterothalic (two
mycelia reproduce sexually)
b. Asexual:
•Asexual reproduction takes place by spores
•Fungal spores are variable in:
colour, size,
rough
surface: smooth
spherical
shape:
kidney
spiny
pear
needle
ovoid
spindle
fusiform
number of cells:
unicellular
bicellular
multicellular
arrangement: solitary
chain
cluster
•According to manner by which spores are borne
on the mycelium, there are two types:
Sporangiospores
Conidia
•Sporangiospores: •Asexual spores produced
internally in a sac like structure called sporangium,
borne on specialized hyphae called sporangiophore
•Sporangiospores may be: motile or non motile
Motile
•Called zoospores
•The sporangia called zoosporangia
•They may have one or two flagella similar or
different (tinsel, whiplash)
•They may fixed anteriorly or posteriorly or
ventrally
Non motile
•Called a planospores
•Are disseminated by wind current
•Conidia:
•Asexual non motile spores produced
externally on a special hyphae called conidiophore
•Conidia may formed singly (phytophthora) or in
chain (penicillium)
•Conidiophores may be free from each other or
aggregated to form the following compound
structures
pycnidium
acervulus
sporodocium
C. Vegetative:
1. Fragmentation: The mycelium breaks up into
fragments, each fragment germinate into a new
individual under favorable conditions
2. Oidia: The hyphae break up into small oval or
rounded segments
hyphae
3. Chlamydospore:
thick walled
Certain cells of hyphae become
chlamydospore
4. Fission: In unicellular true fungi (Yeast), the
vegetative cell splits into two equal daughter cells
5. Budding: As in Yeast, the vegetative cell produces
a small out growth (bud) which is finally separated
from the mother cell and form a new cell
6. Sclerotia:
Hardened & resistant
bodies
•Sporangium: Asexual sac like structure, carried on
special hyphae called sporangiophores containing
several sporangiospores
•Sporangiospores: Asexual spores produced internally
in a sac like structure called sporangium, borne on
specialized hyphae called sporangiophore.
•Conidia: Asexual non motile spores produced
externally on a special hyphae called conidiophore
•Conidiosporangium: Asexual spores, which may be
germinate directly as conidium or sporangium (give
several spores which release and germinates)
5- Classification of fungi
•Based on:
Somatic structure
Sexual reproduction
1.Somatic structure:
Plasmodium
Rudimentary
mycelium
Filamentous
Unicellular
(Yeast)
2.Sexual reproduction:
•Fungi are classified as following:
Kingdom: Mycota
Subkingdom: Myxomycota
(Slime moulds)
Subkingdom: Eumycota
(True Moulds)
•The vegetative phase is
plasmodium
•Classified according to
the method of sexual
reproduction
Plasmodium: •Slimy, naked, multinucleate mass of
protoplasm
•Classification of true moulds:
Chytridomycota
Oomycota
Zygomycota
Deuteromycota
Basidiomycota
Ascomycota
Chytridomycota
•Mostly unicellular fungi, occurring in several habitats as
soil, roots, rumen of cows
•Asexual & sexual spores are produced in sporangia
and release as zoospores
zygote
oospore
oosphere
Meiosis
zoosporangium
fertilization
antherozoid
Oomycota
•Reproduce sexually by oogonia eggs
•The mycelium is non septated except under sexual and
asexual organs
•Reproduce asexually by zoospores .
Zygomycota
•Reproduce sexually by zygospore
•The mycelium is non septated except under sexual and
asexual organs
•Reproduce asexually by sporangia or conidia
•Lacking motile spores
Ascomycota
•They have ascospore borne inside ascus
•The mycelium is septated
•Reproduce asexually by conidia
Basidiomycota
•They have basidiospore borne externally on a basidium
•The mycelium is septated with a very characterized
swelling called clamp connection which have a role in
nuclear migration
•Reproduce asexually by conidia
• Lacking motile spores
Deuteromycota
•Called fungi imperfecti
•Don’t have sexual state in their life cycle
•The mycelium is septated