Doenças causadas por fungos em plantas

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Plant diseases caused by fungi, which (almost) changed the world ....
 Phytophthora infestans, potato - Irland
 Bipolaris oryzae (Helminthosporium), rice – India
 Hemileia vastatrix, Coffee leaf rust – Sri Lanka
 Fusarium oxysporum f. sp. cubense, Banana, “Panama disease”
 Pseudocercospora ulei, rubber tree, “South American leaf blight”
 Phakopsora pachyrhizi, Soy bean, “asian leaf rust”
 Mycosphaerella fijiensis (Cercospora), banana, “black sigatoka”
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
< PFP 520 Myc General Introduction 2022 M_1 >
1 Fungi that cause disease in the field
2 Fungi related to quality and safety of food and feed
3 The good guys – beneficial fungi, or used in biotechnological
processes
Fungi of interest in Agriculture – a link to plant pathology
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
1 Fungi that cause disease in the field
i. Aerial part, foliar diseases:
Alternaria, Pyricularia, Cercospora, Bipolaris etc.
ii. Soil borne fungi:
Sclerotinia. Rhizoctonia e Sclerotium. Pythium
iii. Fungi that colonize the vascular system :
Fusarium, Verticillium, Moniliophthora ( Crinipellis )
Relevant, associated issues:
 Pathogen is saprotrophic, biotrophic, hemibiotrophic ?
 How works propagation and transmission ?
 How do it survive and where is the inicial inoculum ?
 Management and control of diseases ?
Fungi of interest in Agriculture – a link to plant pathology
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
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2 Fungi related to quality and safety of food and feed
i. Post harvest diseases : main issue are fruits !
ii. Producers of mycotoxins : Aspergillus, Penicillium, Fusarium
iii. Fungi transmitted by seeds
iv. Quarentenary pathogens or diseases
3 The good guys – beneficial fungi, biotechnological processes
i. Biological control agents - mycoparasites:
Trichoderma, Clonostachys etc.
ii. Biological control agents – parasites of arthropodes:
Metarhizium, Beauveria, Cordyceps etc.
iii. Growth promoters; fungi that form mycorrhiza
iv. Fungi used in other biotechnological processes
Fungi of interest in Agriculture – a link to plant pathology
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
“fungi” are ...
Eucarionts – like plants and animals
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
Produce as constitutive parts of its cell wall
chitin  Kingdom FUNGI
cellulose  Kingdom CHROMISTA !!? 
fungi are ... 
PFP 520 - Micologia 2022
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Form septate and aseptate hyphae with apical growth !!
Mycelium. “filamentous fungi” 
Unicellular fungi: yeasts
fungi are ...
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
Produce spores in a sexual and an asexual stage of the life cycle
fungi are ...
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
The most important decomposer organisms of
organic matter in nature
fungi are ...
PFP 520 – Micologia 2022
Prof. Ludwig - DFP
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“A non-monophyletic group of eucariotic organisms, 
which share morphological and nutritional characters”
Definition by Berry, 1988
“ fungi “ are ...
Prof. Ludwig - DFP
PFP 520 – Micologia 2022
 Characterization
 Classification
 Identification
PFP 520 – Micologia 2022
Basic Concepts -1
Working with fungi.
Prof. Ludwig - DFP
Characterization – how it works
1. Comparative Morphology
2. Biology
3. Biochemistry
4. Ultrastruture
5. Molecular Biology Techniques
PFP 520 – Micologia 2022
Working with fungi.
Prof. Ludwig - DFP
5
Characterization – how it works -1
1. Comparative Morphology
2. Biology – de Bary 1884
 Life cycle - Ontogeny
 Reproductive structures
 Ecological adaptations: environment, habitat, substrate, host 
 vegetative compatibility – VCG; or AG’s
 sexual compatibility – mating populations, biological species
PFP 520 – Micologia 2022
Working with fungi.
Prof. Ludwig - DFP
3. Biochemistry
Chemistry of the cell wall
Lysine biosysnthesis
Fatty acid profiles
Metabolite and protein profiling, MALDI-TOF
4. Ultrastructure
Septal pore, nuclear division
Mitochondrial christae, flagelar apparatus, haustoria etc.
PFP 520 – Micologia 2022
Characterization – how it works -2
Working with fungi.
Prof. Ludwig - DFP
5. Molecular Biology Techniques
 Molecular markers - Fingerprinting
AFLP, microssatelites etc. Populational studies
 Sequencing of barcode genes, phylogenetic analyses: 
barcode regions: elongation fator, beta-tubuline, 
histone, actine, calmoduline etc.;
“house-keeping genes”
 rtPCR; Diagnosis and monitoring of plant pathogens
PFP 520 – Micologia 2022
Characterization – how it works -3
Working with fungi.
Prof. Ludwig - DFP
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Classification – grouping
Taxonomy – “ man made “
Nomenclature – rules for taxonomy
Systematics –
assembling of groups (taxa) in a hierarchical system
Prof. Ludwig - DFP
PFP 520 – Micologia 2022
Basic Concepts
Working with fungi.
Classification – taxon, pl. taxa
Different systems ....
Morphology based ...??
a modern paradigm:
“Phylogenetic System of Classification”
PFP 520 – Micologia 2022
Taxa have to be monophyletic !
polyphyletic (or non-monophyletic) or paraphyletic
groups are not allowed
PFP 520 – Micologia 2022
“Phylogenetic System of Classification”
All members within a group, e.g. a Genus or a Family, must 
have a common ancestor
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Nomenclatural hierarchy
International Code of Nomenclature of algae, fungi, and plants ICN
(former: International Code for Botanical Nomenclature ICBN)
Kingdom
Phylum
Class
Order
Family
Genus
Species
Infraspecífic categories : forma specialis, race – somewhat
“old-fashioned” ...
PFP 520 – Micologia 2022
Biology of fungi: 
parasite vs. pathogen; endophyte
What is a species ? What is a name?
Species concepts !!
Ontogeny vc. phylogeny
Prof. Ludwig - DFP
PFP 520 – Micologia 2022
Basic Concepts -2
 Morphology !!
Characterization of field isolates
Common proceedings
Evaluation of morphological characters
In general, the first step in the laboratory
Definition of a morpho-type, or
grouping in morpho-types (if you work with many ....)
Obs. It’s not the same as “identification”, as it is not always possible
to give a name to your field isolate
Prof. Ludwig - DFP
PFP 520 – Micologia 2022
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 Morphology ??
Morphological characters run out before species run out ...
Or in other words:
There are no morphological markers for all different species.
Reflection: How to overcome this challenge ...?
John Leslie
PFP 520 – Micologia 2022
Characterization of field isolates
Common procedure
Classification of “fungi “
 Kingdom FUNGI
 Kingdom CHROMISTA
Phylum Peronosporomycota (Oomycota)
ex. Phytophthora, Saprolegnia
 Kingdom PROTOZOA
“myxomycetes”, a polyphyletic group
There are “fungi” in three distinct Kingdoms.
PFP 520 – Micologia 2022
Kingdom FUNGI
Phylum Chytridiomycota
Phylum Zygomycota
Phylum Glomeromycota
Phylum Basidiomycota
Phylum Ascomycota
Deuteromycetes
Anamorphic Fungi
Mitosporic Fungi
Fungi Imperfecti
Prof. Ludwig - DFP
PFP 520 – Micologia 2022
Classification of “fungi “
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Prof. Ludwig - DFP
PFP 520 – Micologia 2022
Summary
 Relevance of fungi in agriculture and related areas
 Biological characterístics of fungi
 Basic concepts
 Characterization and Classification – elements, approaches
 Phylogenetic System of Classification
 “fungi” – a non-monophyletic group of organisms
Further reading
Webster & Weber 2007, Chap. 1, pp. 1-39, parts
Chap. 8, 226 ff. 
Agrios 2005, Chap. 11, parts
Deacon 2006, Fungal Biology.