Características e Classificação dos Fungos Ascomicetos

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 Eucaryotes
 Cell wall constituents are chitin or cellulose
 Spores are formed in a sexual and asexual stage
 Heterotrophs, nutrition by absorption, after release of
exoenzimes
 Hyphae are septate or aseptate, forming a mycelium
 Unicellular forms: yeasts or yeast-like stages
 Most important decomposers of organic matter in nature.
“fungi” are ...
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Structures, Life Cycle M_2
Three key characters of fungi ...!
i. Heterotrophy
ii. Hyphae, with apical growth
iii. Production of spores in a sexual and asexual stage
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A non-monophyletic group of eucaryotic organisms, 
which share morphological and nutritional characters
“ fungi are ...“
Classification of “fungi “
 Kingdom FUNGI
 Kingdom CHROMISTA
Phylum Peronosporomycota (Oomycota)
ex. Phytophthora, Saprolegnia. Mildews.
 Kingdom PROTOZOA
“myxomycetes”, a polyphyletic group
There are “fungi” in three distinct Kingdoms :
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Kingdom FUNGI
Phylum Chytridiomycota
Phylum Zygomycota
Phylum Glomeromycota
Phylum Basidiomycota
Phylum Ascomycota
Deuteromycetes
Anamorphic Fungi
Mitosporic Fungi
Fungi Imperfecti
Prof. Ludwig - DFP
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Classification of “fungi “
Phylum Ascomycota
Kingdom FUNGI
 Life cycle
 Sexual morph or sexual phase (teleomorph)
 Typology of the ascus and the ascocarp
 Asexual morph or assexual phase (anamorph)
 Structures of the asexual phase
 Some terminology
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Asexual stage
Anamorph
Deuteromycetes
Mitosporic Fungi
Imperfect Fungi
Ascomycota
Sexual stage
Teleomorph
Mitoses 
Mitospore, conidium
Plasmogamy, Caryogamy, Meiosis
Meiospore, ascospore
Propagation,
Epidemy in the field !!
Generates genetic variability
Structures of resistence and survival
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Ascomycota : sexual and asexual reproduction
Asexual
Stage
two phenotypes
But it is the same genotype !!
Fusarium 
graminearum
Gibberella zeae
Sexual 
Stage
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Asexual stage
Anamorph
Fusarium
Ascomycota
Sexual stage
Teleomorph
Gibberella
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1- One fungus – One name
Amsterdam Declaration on fungal nomenclature
April 2011
1
Recognizes the need for 
1. an orderly transition to a single-name nomenclatural 
system for all fungi, and
2. to provide mechanisms to protect names that otherwise 
then become endangered.
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18th International Botanical Congress in Melbourne,
Australia July 2011
Changes will take effect on 1 January 2012. 
 International Code of Nomenclature of algae, fungi, and plants ICN
(former: International Code for Botanical Nomenclature ICBN) 
 Code will allow for the electronic publication of names of new taxa.
 Either English or Latin is allowed for essential components of the 
publication of a new name. 
 Names of new fungi will require the citation of a unique identifier 
issued by a recognized repository that will register the name, e.g. 
MycoBank (CBS)
 Adoption of the principle of “one fungus, one name”.
Hawksworth DL (2011) 
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2- One fungus – Which name ? April 2012
3- One fungus – Which gene ? April 2013
CBS Spring Symposium, http://www.cbs.knaw.nl
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Asexual stage
Anamorph
Fusarium
Colletotrichum
Clonostachys
Pyricularia
Cercospora
Phyllosticta
Oidium
Penicillium
Aspergillus
Ascomycota
Sexual stage
Teleomorph
Gibberella
Glomerella
Bionectria
Magnaporthe
Mycosphaerella
Guignardia
Erysiphe
Eupenicillium
Eurotium
fusariosis, gibberella
anthracnosis
biological control
brusone
sigatoka, cercosporiose
mancha preta do Citrus MPC
powdery mildews, oídios
mycotoxins
mycotoxins
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Fase
 assexuada
micélio vegetativo
"n"
"n"
"n"
"n"
"n"
"n" + "n"
dicárion
asco
Ascósporos
(meiósporos)
"n"
Conídios
(mitósporos)
 "n"
2 "n"
P !
C ! M !
Fase sexuada
Life cycle of an
ascomycete
Prof. Ludwig - DFP
asexual
sexual
Sphaerotheca pannosa
Agrios 2005, p. 451
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Conidium, spore
Conidiogenous cell
Conidiophore
Hypha - mycelium
Production of asexual spores - conidia
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Production of sexual spores, ascospores
Perithecium
Fruiting body or ascocarp
Ascus
Ascospores
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Ascomycota : structures of the sexual stage -1
1- ascospores formed in asci
It is a sporangium, where spores are formed, as a product of meiosis
2- Typology of the ascus
Prototunicate
Not differenciated
Unitunicate
Differenciated apical structure
Spores are set free actively
Bitunicate
Spores are set free actively
“jack-in-the-box”
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Cleistothecium
Apothecium
Perithecium:
free, superficial
Typology of the fruiting body, ascocarp or ascoma
Ascostroma, has a different ontogeny
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Ascomycota : structures of the sexual stage -2
immersed
Phylum Ascomycota
Asexual stage – conidiogenesis
1 Thallic
2 Blastic a holoblastic
b enteroblastic
i. enteroblastic - tretic
ii. enteroblastic - phialidic
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Historically, there are not natural groupings, according to characters of
the spores
Ellis 1971. Dematiaceous Hyphomycetes.
asexual stage, “anamorphs” – big groups
“hyphomycetes” – conidophore is simple and free
pigmented – “dematiales”
hyaline – ”moniliales”
synemium, sporodochium
“coelomycetes” - produce pycnidia or acervuli
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Historically, there are not natural groupings, according to characters of
the mycelium and reproductive structures (sporulation)
Phylum Ascomycota
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“moniliales” 
hyaline hyphomycetes, with a simple conidiophore
Penicillium citrinum
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sporodochium
Fusarium
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“dematiales”
pigmented hyphomycetes, with a simple conidiophore
Bipolaris
Complex : 
Helminthosporium-
like
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Helminthosporiosis
Host: Maize
25
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Bipolaris
Complex : 
Helminthosporium-
like fungi
Leaf spot disease, “mancha alvo”
Hosts: soybean, coffee tree etc. 
26
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Corynespora cassiicola
Complex : Helminthosporium-like
Leaf spot disease, Helminthosporiosis
Hosts: grasses 27
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Curvularia
Complex : Helminthosporium-like
10
Hosts: soybean, coffee tree, banana etc.
Cercospora - Mycosphaerella
28
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Doença: Mancha Angular
Host: common bean
Pseudocercospora griseola
29
Phaeoisariopsis griseola
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synemium
Acervulus
“coelomycetes” - produce pycnidia or acervuli
Pycnidium
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Colletotrichum gloeosporioides – is a species complex !
C. graminicola - maize
C. falcatum - sugarcane
C. truncatum - soybean
Anthracnosis, Post-harvest diseases
Hosts: several
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Phoma tarda
Phoma leaf spot of the coffee tree
Pycnidium
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“coelomycetes” - produce pycnidia or acervuli
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Sexual stage : Didymella
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Phoma tarda
Phoma leaf spot of the coffee tree
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Lasiodiplodia
Stem die-back
Post-harvest disease
Hosts: mango tree, Coco nuts
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Further Reading
Agrios 2005.
Chapter 11: Plant diseases caused by Fungi. Parts of.
Webster & Weber 2007.
Chapter 1: Introduction
Ellis 1971. Dematiaceous Hyphomycetes.
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Prof. Ludwig
Summary
 Life cycle of ascomycetes, phenotype and genotype
 One fungus, one name
 Structures of the sexual and the asexual stage
 Some terminology