1 fungi. 2 how fungi affect other organisms fungi may be harmful (parasites), or helpful, or even...
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Fungi
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How Fungi Affect Other Organisms
Fungi may be harmful (parasites), or helpful, or even necessary to other organisms.
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How Fungi Affect Other Organisms
Fungi and Disease• Cause many serious diseases – both in
plants and animalsIn plants – • Mildew• Dutch Elm Disease• Chestnut Blight• Corn smut and other
crop diseases
https://www.flickr.com/photos/judybaxter/1227037/
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How Fungi Affect Other Organisms
Fungi and Disease• Fungi that grow on
foods can produce chemicals that are toxic (poisonous) when eaten– Ergot of Rye causes ergot
poisoning that can be fatal Claviceps purpurea, the fungus that causes ergot poisoning; fruiting body growing on barleyPublic Domain http://en.wikipedia.org/wiki/File:Claviceps_purpurea.JPG
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How Fungi Affect Other Organisms
Fungi and Disease• Fungi that grow on
foods can produce chemicals that are toxic (poisonous) when eaten– Aflatoxin – cancer causing in
small doses, fatal in large doses, produced by a fungus that grows in stored corn or peanuts
Aspergillus, the fungus that produced aflatoxin, growing on peanuts
Photo by International Institute of Tropical Agriculture
Attribution-NonCommercial License https://www.flickr.com/photos/iita-media-library/4751580303/
FYI: Aflatoxin comes from Aspergillus + flavus + toxin
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How Fungi Affect Other Organisms
Fungi and Disease• Fungi also cause
– Athlete’s Foot– Ringworm– Lung disease in poultry
• Some fungi can be used to help control insect pests, for example Gypsy Moth caterpillars.
RingwormPhoto by Grook Da Oger http://commons.wikimedia.org/wiki/File:Herpes_circin%C3%A9_01.jpg
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How Fungi Affect Other Organisms
Fungus-Root Associations• Occur in ~80% of plants• A mutualistic association• 2 types caused by different
kinds of fungi
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How Fungi Affect Other Organisms
Fungus-Root Associations1. Endomycorrhizae (also
called vesicular-arbuscular mycorrhizae) – part of the fungus grows within
the cells of the roots – found on most flowering
plants, including grasses (Angiosperms)
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How Fungi Affect Other Organisms
Fungus-Root Associations
1. Endomycorrhizae
Public Domain: http://en.wikipedia.org/wiki/File:Arbuscular_mycorrhiza_microscope.jpg
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How Fungi Affect Other Organisms
Fungus-Root Associations2. Ectomycorrhizae
–grows around the root and in-between the outer cells of the root
– does not enter the cell–gives roots a thickened appearance– primarily on woody trees and
shrubs including all pines, willow, oak and beech trees
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How Fungi Affect Other Organisms
Fungus-Root Associations
2. Ectomycorrhizae
Ectomycorrhizae on pine rootsPhoto by Randy Molina, Public Domain, a work of the Forest
Service of the United States Department of Agriculture
http://commons.wikimedia.org/wiki/File:Ectomycorrhizae_001.jpg
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How Fungi Affect Other Organisms
Fungus-Root Associations
Benefits to plants:
1. Increase the solubility of minerals in the soil – particularly phosphorus
2. Improves the uptake of nutrients (N, P, K) for the host
3. Protects against plant pathogens
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How Fungi Affect Other Organisms
Fungus-Root Associations
Benefits to plants:
4. Produces plant growth hormones
5. Moves carbohydrates from one plant to another (vital for non-green plants such as Indian Pipe)
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How Fungi Affect Other Organisms
Fungus-Root Associations
Benefits to Fungi–A source of carbohydrate
(food)
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How Fungi Affect Other Organisms
Lichens:• A mutualistic relationship
between a fungus and an alga
• The alga is autotrophic and produces food.
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How Fungi Affect Other Organisms
Lichens:• The fungus provides water
and minerals for the alga.• Together they can live in
many places neither could survive alone, and where few or no other organisms can live either.
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How Fungi Affect Other Organisms
Lichens:• Release acids that breakdown rock
so are often the first organisms to grow in barren rocky areas
• Are the primary source of food for reindeer and caribou in wintertime
• Are important indicators of air pollution (They do not grow well if air is polluted.)
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Lichens
British SoldiersPhoto by Louise K. Broman, Public Domain:
http://en.wikipedia.org/wiki/File:Cladonia_cristatella_EPA.jpg
Reindeer LichenPhoto by Jason Hollinger
http://commons.wikimedia.org/wiki/File:Shrubby_Reindeer_Lichen_(2451758190).jpg
Wolf LichenPhoto by Jason Hollinger
http://en.wikipedia.org/wiki/File:Letharia_vulpina_JHollinger_crop.jpg
Public Domain: http://en.wikipedia.org/wiki/File:Lichen_reproduction1.jpg
Photo by Roantrum http://en.wikipedia.org/wiki/File:N2_Lichen.jpg
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