Biology I Presentation
FUNGI
We will learn
General characteristics of fungi
Structure of fungi
Economic Importance
Pathogenicity
Brief intro of some fungi
THE SIX KINGDOMS
Fungi are placed in a separate kingdom called the kingdom fungi
OF FUNGI
CHARACTERISTICS
The Characteristics of Fungi
Fungi are NOT plants
Nonphotosynthetic
Eukaryotes
Nonmotile
Most are saprobes (live on dead organisms)
The Characteristics of Fungi
Absorptive heterotrophs (digest food first & then absorb it into their bodies
Release digestive enzymes to break down organic material or their host
Store food energy as glycogen
The Characteristics of Fungi
Important decomposers & recyclers of nutrients in the environment
Most are multicellular, except unicellular yeast
Lack true roots, stems or leaves
fungi as a decomposers
The Characteristics of Fungi
Cell walls are made of chitin (complex polysaccharide)
Body is called the Thallus
Grow as microscopic tubes or filaments called hyphae
The Characteristics of Fungi
Some fungi are internal or external parasites
A few fungi act like predators & capture prey like roundworms
The Characteristics of Fungi
Some are edible, while others are poisonous
The Characteristics of Fungi
Produce both sexual and asexual spores
Classified by their sexual reproductive structures
The Characteristics of Fungi
Grow best in warm, moist environments
Mycology is the study of fungi
Mycologists study fungi
A fungicide is a chemical used to kill fungi
The Characteristics of Fungi
Fungi include puffballs, yeasts, mushrooms, toadstools, rusts, smuts, ringworm, and molds
The antibiotic penicillin is made by the Penicillium mold
FUNGI SIZE
NON-REPRODUCTIVE
Vegetative Structures
Hyphae
Tubular shape
ONE continuous cell
Filled with cytoplasm & nuclei
Multinucleate
Hard cell wall of chitin also in insect exoskeletons
Hyphae
Stolons – horizontal hyphae that connect groups of hyphae to each other
Rhizoids – rootlike parts of hyphae that anchor the fungus
Hyphae
Cross-walls called SEPTA may form compartments
Septa have pores for movement of cytoplasm
Form network called mycelia that run through the thallus (body)
Absorptive Heterotroph
Fungi get carbon from organic sources
Tips of Hyphae release enzymes
Enzymatic breakdown of substrate
Products diffuse back into hyphae
Modifications of hyphae
Fungi may be classified based on cell division (with or without cytokinesis)
Aseptate or coenocytic (without septa)
Septate (with septa)
Modifications of hyphae
Hyphal growth
Hyphae grow from their tips
Mycelium is an extensive, feeding web of hyphae
Mycelia are the ecologically active bodies of fungi
ASEXUAL & SEXUAL SPORES
REPRODUCTIVE STRUCTURES
REPRODUCTION
Most fungi reproduce Asexually and Sexually by spores
ASEXUAL reproduction is most common method & produces genetically identical organisms
Fungi reproduce SEXUALLY when conditions are poor & nutrients
6. THE CHARACTERISTICS OF FUNGI
Fungi are NOT plants
Nonphotosynthetic
Eukaryotes
Nonmotile
Most are saprobes
(live on dead
organisms)
6
7. THE CHARACTERISTICS OF FUNGI
Absorptive heterotrophs
(digest food first & then
absorb it into their bodies
Release digestive enzymes to
break down organic material
or their host
Store food energy as
glycogen
7
BREAD MOLD
8. THE CHARACTERISTICS OF FUNGI
Important decomposers
& recyclers of nutrients
in the environment
Most are multicellular,
except unicellular yeast
Lack true roots, stems
or leaves
8
MULTICELLULAR
MUSHROOM
UNICELLULAR YEAST
10. THE CHARACTERISTICS OF FUNGI
Cell walls are made of chitin
(complex polysaccharide)
Body is called the Thallus
Grow as microscopic tubes
or filaments called hyphae
10
11. THE CHARACTERISTICS OF FUNGI
Some fungi are internal or
external parasites
A few fungi act like predators &
capture prey like roundworms
11
Predaceous
Fungi feeding on
a Nematode
(roundworm)
12. THE CHARACTERISTICS OF FUNGI
Some are edible, while others
are poisonous
12
EDIBLE POISONOUS
13. THE CHARACTERISTICS OF FUNGI
Produce both
sexual and
asexual spores
Classified by
their sexual
reproductive
structures
13
Spores come
in various
shapes
14. THE CHARACTERISTICS OF FUNGI
Grow best in warm, moist
environments
Mycology is the study of fungi
Mycologists study fungi
A fungicide is a chemical used to
kill fungi
14
Fungicide kills
leaf fungus
15. THE CHARACTERISTICS OF FUNGI
Fungi include puffballs,
yeasts, mushrooms,
toadstools, rusts,
smuts, ringworm, and
molds
The antibiotic penicillin
is made by the
Penicillium mold
15
Penicillium mold
Puffball
18. HYPHAE
18
Tubular shape
ONE continuous cell
Filled with cytoplasm
& nuclei
Multinucleate
Hard cell wall of
chitin also in insect
exoskeletons
19. HYPHAE
Stolons –
horizontal hyphae
that connect
groups of hyphae
to each other
Rhizoids – rootlike
parts of hyphae
that anchor the
fungus
19
STOLON
RHIZOIDS
20. HYPHAE
Cross-walls called
SEPTA may form
compartments
Septa have pores for
movement of
cytoplasm
Form network called
mycelia that run
through the thallus
(body)
20
21. ABSORPTIVE HETEROTROPH
Fungi get carbon from organic sources
Tips of Hyphae release enzymes
Enzymatic breakdown of substrate
Products diffuse back into hyphae
Digested material is then used by the hypha
Nucleus “directs” the digestive
process
22. MODIFICATIONS OF HYPHAE
Fungi may be classified based on
cell division (with or without cytokinesis)
Aseptate or coenocytic (without septa)
Septate (with septa)
22
NO CROSS
WALLS CROSS
WALLS
24. HYPHAL GROWTH
Hyphae grow from their tips
Mycelium is an extensive, feeding
web of hyphae
Mycelia are the ecologically active
bodies of fungi
24
This wall is rigid Only the tip wall is plastic and stretches
26. REPRODUCTION
Most fungi reproduce Asexually and
Sexually by spores
ASEXUAL reproduction is most
common method & produces
genetically identical organisms
Fungi reproduce SEXUALLY when
conditions are poor & nutrients
scarce
26
27. SPORES
Spores are an adaptation to life on
land
Ensure that the species will
disperse to new locations
Each spore contains a reproductive
cell that forms a new organism
Nonmotile
Dispersed by wind
27
28. HYPHAL GROWTH FROM SPORE
28
Mycelia have a huge surface area
More surface area aids digestion & absorption of food
mycelium
Germinating spore
31. SEXUAL REPRODUCTION
Used when environmental
conditions are poor (lack
of nutrients, space,
moisture…)
No male or female fungi
Some fungi show
dimorphism
May grow as MYCELIA
or a YEAST –LIKE
state (Filament at 25oC
& Round at 37oC)
31
Dimorphic Fungi
32. SEXUAL REPRODUCTION
Haploid 1n hyphae from 2 mating types
(+ and -) FUSE (Fertilization)
Forms a hyphae with 2 nuclei that
becomes a ZYGOTE
The zygote divides to make a SPORE
32
+ -
SPORE FORMS
34. THREE TYPES OF ASEXUAL REPRODUCTION
Fragmentation – part of the mycelium
becomes separated & begins a life of its
own
Budding – a small cell forms & gets
pinched off as it grows to full size
Used by yeasts
Asexual spores – production of spores by
a single mycelium
34
35. REPRODUCE BY SPORES
Spores may be Formed:
Directly on hyphae
Inside sporangia
On Fruiting bodies
Amanita fruiting body
Pilobolus sporangia
Penicillium
hyphae
36. ASEXUAL REPRODUCTION
Fruiting Bodies are modified hyphae
that make asexual spores
An upright stalk called the
Sporangiosphore supports the spore
case or Sporangium
36
38. MAJOR GROUPS OF FUNGI
Within the past
few years, several
groups have been
re-classified into
the protists
Two of these
groups are the
slime molds and
water molds
39. Classification by Nutrition
Saprobes
Decomposers
Molds, mushrooms, etc.
Parasites
Harm host
Rusts and smuts (attack plants)
Mutualists
Both benefit
Lichens
Mycorrhizas
39
40. MAJOR GROUPS OF FUNGI
Basidiomycota – Club Fungi
Zygomycota – Bread Molds
Chytridiomycota – Chytrids
AM Fungi - Mycorrhizas
Ascomycota – Sac Fungi
Lichens – Symbiosis (algae & Fungi)
44. HUMAN-FUNGUS INTERACTIONS
Beneficial Effects of Fungi
Decomposition - nutrient and carbon recycling.
Biosynthetic factories. Can be used to produce
drugs, antibiotics, alcohol, acids, food (e.g.,
fermented products, mushrooms).
Model organisms for biochemical and genetic
studies.
Production of vitamin
Hormone production
Edible fungi
Production of insecticides
45. FUNGI FORM BENEFICIAL PARTNERSHIPS
(SYMBIOSIS) WITH OTHER ORGANISMS SUCH AS
TREES AND FLOWERING PLANTS:
Lichen – symbiotic
relationship between algae
and fungi
Algae
hyphae
46. HUMAN-FUNGUS INTERACTIONS
Harmful Effects of Fungi
Destruction of food, lumber, paper, and cloth.
Plant diseases.
Animal diseases
human diseases, including allergies.
Toxins produced by poisonous mushrooms and
within food (e.g., grain, cheese, etc.).
51. HABIT AND HABITAT
Puccinia are generally known as rust fungi.
700 species
They are parasites on plants(wheat,
coffee, beans etc).
It is an internal obligate parasite.
They are generally heteroecious, i.e
requiring two hosts to complete life
cycle.
52. MORPHOLOGICAL FEATURES
Delicate septate mycellia
. It is intercellular
sending out haustoria in the host cells
penetrating the host cell causes
hypertrophy, distortion and malformation
The mycelium is monokaryotic on
secondary host and dikaryotic on primary
host
55. REPRODUCTION
life cycle on two different hosts.
The diplophase (2n) stage is a parasite on wheat
while
the haplophase (1n) stage on an alternate host
which is Barberry vulgaris.
We’ll take example of Puccin graminisia
56. LIFE CYCLE
Its life cycle spreads over five stages,
which are
a.Uredinial stage:-
b.Telial stage:-
c.Basidial stage:-
d.Spermogonial stage or pycnidial
stage:-
e.Aecial or Aecidial stage:-
58. A.UREDINIAL STAGE:-
first or rust stage.
appear on culms,
The pustule is called a Uredinium,
which on maturity bursts and releases
uredospores.
Each uredospore is a binucleate
Lying together -red-rust like appearance
readily germinate on wheat plant
59. Wheat rust ( Puccinia ) Uredospores are small, roughly
circular, thick-walled reddish
spores found within ruptured
rust...
60. B.TELIAL STAGE:-
dark brown or black pustules
occur in the form of streaks called telia
Containing teliospores or teleutospores
(dark brown )
diploid nucleus
62. C.BASIDIAL STAGE:-
, nuclear fusion
a row of four haploid nucleus.
This four celled structure is called a
promycelium or epibasidium
Tube formation…-basidiospore
Formation of spores
each spore is either of + or – strain
Basidiospore detach… now ready to infect
63. D.SPERMOGONIAL STAGE OR
PYCNIDIAL STAGE:-
basidiospores germinate . to attack barberry
leaves
mycelia spreads ( huastoria)
barberry protoplasm ( their only food )
Monokaryotic mycellium (+ or – strain )
Afterfour days 2 structure formed
1.Pycnia or spermogonia on upper surface
2.Aedia or cluster cups on ventral surface
64. E.AECIAL OR AECIDIAL STAGE:-
Aecia, aecidia or cluster cups are
produced as little yellow cups on ventral
surface of barberry leaf.
65. AECIAL OR AECIDIAL STAGE
Spermatization
Formation of aecidiospores.
These are binucleate and brightly yellow
coloured and they germinate on wheat
blown by wind
having six germ pores
Entering in host through stomata
Life cycle continues
66. ECONOMIC IMPORTANCE:-
Puccinina graminis tritici causes black or
stem rust,
P. recondita causes brown or orange leaf
rust
P.coronata brown rust of wheat
P. sorghi causes leaf rust of corn
69. SYSTEMATIC POSITION
Division Mycota
Sub division Eumycota
Class Basidiomycetes
Order Ustilagonales
Family Ustilaginaceae
70. HABIT AND HABITAT:
400 species
internal parasites of plants
Causing diseases called smuts because
of black coloured spores.
71. VEGETATIVE STRUCTURE:
mycelium may be primary or secondary.
Primary mycelium is uninucleate and is called
monokaryotic mycelium.
Secondary mycelium is septate, dikaryotic and
spreads throughout interior of the host plant
Firstly intracellular and later on becomes
intercellular.
Mycelluim sending huastoria into the host
infection appearance in flowering stage (loose
smut )
, dark brown powder, ( easily blown by wind )
And host destroyed
72. REPRODUCTION:
Chlamydospore formation
mycellium accumulation
Division and redivision
Hyphae swelling
brandspores, smut spores or
chlamydospores, formation ( the black
spores )
beaded appearance to the hyphae.
This rusty mass or group of black spores
is called the smut
74. CHLAMYDOSPORE
rounded or oval in shape
covered by a two layered wall
outer thick layer called exospore
an inner delicate and smoothn layer called
endosperm.
after dispersal fall on soil and lead a
saprophytic life
basisiospore or a sporidium formation
Germination
.after germination basidiospores are
capable of infecting
79. ECONOMIC IMPORTANCE:
2.it causes about 1% damage in the planes
and around 10-20% in foot hills and humid
places of Pakistan.
3. Covered smut of barley is caused by
U.hordei and U.nuda.