Download Nutritional Status - Missouri State University

• Morphology
• Reproduction
• Ecology
• Dissemination
SEM of an unidentified fungus on the surface of a seed from Setaria faberii, a large grass, commonly called Giant Foxtail
--www.itg.uiuc.edu/ exhibits/iotw/2002-08-29/
• Eukaryotes
• Non-Vascular
• Reproduce by Spores
• Heterotrophs
– Can’t Make Their Own Food
– Digest then Ingest
• Lack of Chlorophyll Profoundly
Affects Lifestyle
– Both Sexual & Asexual Spores
– Alternation of Generations
• Vegetative Body Microscopic Threads Called
Hyphae
• Cell Walls Similar in Structure to Plants
– Differ in Chemical Composition
• Organelles & their Structures Differ from
Plants
• More closely Related to Animals than Plants
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Not Dependent on Light
Can Occupy Dark Habitats
Can Grow in any Direction
Can Invade the Interior of Substrate with
Absorptive Filaments
midamericalandrestore.com
• Mycelium
– Filamentous Body with Many Cells
• Hypha
– Individual Branches of Mycelium
• Size Varies, Growth at Hyphae Tips
• Haustoria
– Feeding Organs
• Sclerotium
– Hard Masses of Mycelium
http://www.earthfoot.org/backyard/fungi.html;
http://www.ent.iastate.edu/imagegal/plantpath/barley/1785.15ergotinbarley.html
midamericalandrestore.com
Nutritional Status
• Saprophytes
– Recyclers in Nature
• Symbionts (Mutualists)
– Mycorrhizae
– Lichens
• Parasites
answers.com
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• Sporangium
Reproduction
– Sac or Container that Holds Spores
• Chlamydospore
• Mainly by Spores
– Analogous to the Seed of Green Plants
• Successful Organisms
• Enormous Numbers of Spores
• Many Produce Asexual & Sexual Spores
– Sexual or Perfect State Referred to as
Teleomorph
– Asexual or Imperfect Termed the Anamorph
• Spores can Remain Dormant Long Time
http://www.wsl.ch/staff/beat.frey/rem_e.html
– Thick-Walled Spore Formed from Hypha Cell
• Resting Structure for Long-Term Survival
• Zoospores: Spores with Flagella that Swim
• Most Fungi Can Reproduce Sexually
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Mating Types
1. Gametes (Cells) Unite
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Produce Zygote
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Zygospore, Ascospore, Basidiospore, Oospore
2. Gametes Fuse
3. Mycelium Unite
Where Do Fungi Live?
Identification
• Some on Plant
Entire Lives
except Spore Stage
• Spores & SporeBearing Structures
• Sometimes Mycelium
Rust spores parasitized by the mycelium of the hyperparasite that grows appressed to the
rust spores, coiling around them & forming numerous appressoria. Apsnet.org
Monilia fructigena Pers. - Brown Fruit Rot, agroatlas.ru
• Soil Fungal Pathogens
• Some Part of Lives
on Plants & Part on
Dead Tissues of
Same Host on
Ground
http://www.scientificamerican.com/gallery_directory.cfm?photo_id=AAE0EFB0-EF07-327E-2BB7A037CC0DDD55
Which Part of the Plant?
– On Plants
– On Dead Tissues of Host
– As Saprophytes on Decaying OM
– Wide Host Range
– Can Survive in Soil many Years
– Need Host occasionally to Increase Populations
• Plant Surface with
Haustoria
• Intercellularly with
Haustoria
• Xylem Vessels
[(a) Courtesy APS; (b) Courtesy Plant Pathology Department,
Washington State University]
www.microbeorganics.com/
apsnetorg
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What Kind of Plant Material
What Kind of Environment
Do They Require?
Do They Require?
• Obligate Fungi Need
Living Cells
• Usually Presence of Water
• Some Nonobligate Fungi
never Contact Living
Plant Cells
• Zoospores Require Free Water
• Spores Broader Ranges of Temp & Moisture
– Production, Movement & Germination
www.plantcell.org/content/vol17/issue7/cover.dtl
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Impacts of Fungi
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Many Harmful to Humans & Animals
Plant Diseases
Rot & Contamination of Foods
Can Destroy almost every Kind of
Manufactured Good
Many Useful to Humans
Yeasts for Baking & Brewing
Antibiotics & other Drugs
Organic Acids Commercially Produced with
Fungi
– Citric Acid
– Steroids & Hormones
– Certain ‘Stinky’ Cheeses
bio.miami.edu
www.eurobloodsubstitutes.com/euroProject.htm
info.asapsupplier.com
How Do Fungi Spread?
In What Form Do They Spread?
• Zoospores can Move
Short Distances
• Usually as Spores
• Hyphae Fragments & Sclerotia by Wind,
Water, etc.
• Most Fungi Rely on
Chance Distribution
– Wind, Water, Birds,
Insects, Animals,
Humans
omafra.gov.on.ca
www.microbeorganics.com/
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Active or Passive Spread?
Fungi Classes
• Major Classes Based on Method of
Producing Sexual Spores
• Almost always
Passive
• Distance Carried
Depends on Wind,
Water, Insect
Movement
• Some Forcibly
Discharge Spores
Puffing from Apothecia of Monilinia fructicola (brown rot of stone fruits). apsnet.org
1. Ascomycetes
• Sac or Cup Fungi, Spores Borne Internally in
a Sac called Ascus
• 75% of all Fungi
– Most Fungi that Join with Algae to Form Lichens,
Baker’s Yeast, Penicillium chrysogenum
www.fungi.com/gifts/lockwood.html
• Sexual Spores Ascospores
– Called Teleomorph or Perfect Stage
• Sexual Fruiting Bodies Saclike
– Cleistothecium
– Perithecium
– Pseudothecium
– Apothecium
• Have Sexual & Asexual Stages
– Conidia Are Asexual Spores
• Called Anamorph or Imperfect Stage
apsnet.org, Courtesy R. Wick
• Sexual Stage Seldom Found in Nature
• Mostly Found as Mycelium, Conidia or Both
• If Water Present, Can Consume Almost Any
Carbon Substrate
– Jet Fuel, Wall Paint
– Biggest Role in Recycling Dead Plant Material
• Symbiotic Association with Algae or Plants
• Symbioses with Arthropods
– Can Line Beetle Galleries
– Beetles Maintain Pure
Culture of the Fungus
Examples of Ascomycetes
• Aspergillus flavus
– Producer of Aflatoxin
Fungal
Both a Toxin & Most Potent
Known Natural Carcinogen
• Cryphonectria parasitica
– Chestnut Blight
• Ophiostoma ulmi
• Candida albicans
http://www.ipm.iastate.edu/ipm/icm/node/194
4
• Taphrina, Peach
Leaf Curl
• Anthracnose Fungi
• Venturia inaequalis,
• Powdery Mildew
Fungi
Apple Scab
• Sooty Molds
• Fusarium
• Black Spot of Roses
• Verticillium
• Botrytis
• Claviceps, Ergot of
Rye
2. Basiomycetes
• Spores Borne Externally on
Club-Shaped Structure Called
Basidium
• Club & Mushroom Fungi
• Usually Fleshy
• Saprophytes, Wood Decay or Pathogenic
including Root & Stem Rots
• Most Evolutionary Advanced Fungi
• Usually no Asexual Spores
botamynus.de
• Ectomycorrhizae
3. Zygomycetes
• Others Form Symbiotic Associations with
• Sexual Spores Thick-Walled Resting
Zygospores
Insects
• Shiitake
• Mostly Live in Soil or on Decaying Material
• Certain Hallucinogen Toxins
• Asexual Zygospores Borne on Stalks
• Smuts
• ‘Sugar Molds’
• Rusts
• Rhizopus ‘Bread Molds’ & Soft Rots
• Snow Mold of Turfgrasses
• Endomycorrhizae
• Heart Rot of Trees
clarku.edu
Fungal Disease Control
4. Oomycetes
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Formerly Classified as Fungi
Cellulose Cell Wall
Water Molds aka Aquatic Fungi
Filamentous
Absorb Food from Surrounding Water or Soil
Most Saprophytes
Some Cause Severe Diseases
– Late Blight of Potato
– Downy Mildew
– Sudden Oak Death Syndrome
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Resistant Plants
Destroy Infected Debris
Destroy Volunteer Plants or Alternate Hosts
Rotate Crops
Chemical Sprays or Dusts
Sterilize Soil
Systemic Fungicides or Hot Water for Seeds
Control Insect Vectors
protist.i.hosei.ac.jp
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