IMPORTANCE of fungi
Act as decomposers.
cause disease in animals and plants.
essential for many industrial processes involving fermentation.
commercial production of many organic acids and certain drugs.
in manufacture of many antibiotics
acts as important research tools in the study of fundamental biological processes
Sunday, September 28, 2008
NUTRITION & METABOLISM
NUTRITION & METABOLISM
They grow best in dark moist habitats, but they are found wherever organic material is found. Most fungi are saprophytes. They release hydrolytic exoenzymes that digest external substrates, they then absorb the soluble products. They are chemo organoheterotrophs and derive carbon, oxygen and electrons from organic source.
They grow best in dark moist habitats, but they are found wherever organic material is found. Most fungi are saprophytes. They release hydrolytic exoenzymes that digest external substrates, they then absorb the soluble products. They are chemo organoheterotrophs and derive carbon, oxygen and electrons from organic source.
FUNGI STRUCTURE
Structure of Fungi
The main body of most fungi is made up of fine, branching, usually colourless threads called hyphae. Each fungus will have vast numbers of these hyphae, all intertwining to make up a tangled web called the mycelium.
The mycelium is generally too fine to be seen by the naked eye, except where the hyphae are very closely packed together. The picture on the left was taken through a microscope. The hyphae are magnified 100 times life size.
.
Some fungi, such as Honey Fungus, which is a parasite of woodland trees, have hyphae collected together into long cables, called rhizomorphs. Because there are so many hyphae packed together, they are easily seen, forming black 'bootlaces'. These can spread through a woodland infecting neighboring trees.
Fungal mycelium is mostly hidden from human view, not only because of its small size, but also as a result of its location. The tangled mycelial mass is usually hidden deep within its food sources, such as rotting matter in the soil, leaf litter, rotting wood, or dead animals. The mycelium remains undetected until it develops one or more fruiting bodies, containing the reproductive spores.
Fruiting bodies (such as mushrooms) are made up of thick collections of hyphae. They vary in size from small and insignificant, to large eye-catching structures.
They are usually produced at the surface of the food source, rather than hidden within it, to allow the spores to be shed and carried away by the wind, or by water, or animals. The fruiting bodies are usually the only indication we have that a fungus is present. Like icebergs, they represent a tiny fraction of the whole fungus, with most of it being hidden from view.
If you are looking for fungi in Britain, the best time to look is in the autumn. The fungal mycelia have then had a long, relatively warm period to grow extensively over the summer. With the coming of wetter weather in the autumn, damp warm conditions are created which are ideal for fungi to fruit. Many fungi have fruiting seasons in late summer to autumn. However, don't ignore the Spring. This is a good time to look for fungi such as Morels and other cup fungi. Little will be found in cold winter months with frosts, although Oyster mushrooms will continue to grow through most of the winter, as will Jew's Ear.
Fairy Rings
Fungal mycelia tend to grow in more or less circular shapes. This is because they grow by spreading out in all directions from a central point. This central point represents the location of the original spore which germinated to start the fungal mycelium. The mycelium will usually produce fruiting bodies on its outer edge. As a result, the fruiting bodies of fungi living hidden in the soil can sometimes be found in rings - the 'fairy rings' of children's stories.
The Clouded Agaric toadstool (right) is a good example of this. The fruiting bodies can often be found in rings, because they are produced on the outer growing edge of the circular, underground mycelium. The Clouded Agaric can be found in the leaf litter of both coniferous and deciduous woodland.
(image courtesy of Jeff Benn)
Another example is the 'Fairy Ring Toadstool' (Its scientific name is Marasmius oreades). This, in contrast to the Clouded Agaric, grows on grassy expanses such as lawns and golf courses. The fungus can be traced by the rings of dark green grass, with the mushrooms fruiting on the outer edge of the ring. The growth of the ring can be traced year on year. If there are no barriers, rings may grow outwards at up to 20 cm per year. This is a fungus which fruits early in the year, in the spring.
Giants of the natural world
Most people, if asked to name the largest organism on earth, come up with examples such as elephants, blue whales or giant trees, such as Redwoods. In fact, the largest living organism on this planet may well be a fungus!
In America, a single individual fungus, similar to the Honey Fungus already mentioned, was found to cover a staggering 2,200 acres of land. (This is 45 times bigger than the Woodland Education Centre in Offwell, for those of you who have visited the Centre before.)
Some of the oldest living organisms?
We tend to think of fungi as being short-lived, because the visible fruiting bodies which we see don't usually last very long. However, for the fungus to have reached this size, it must have been at least 2,400 years old. It would have been a mere youngster of 400 years old, at the time of Christ's birth.
The rings of Fairy Ring Toadstools found closer to home in Britain, possibly on your back lawn, can also grow to hundreds of meters in diameter, when they are likely to be at least a thousand years old.
Some lichens, which are a partnership between a fungus and an alga, have been estimated to be around 9000 years old!
Next time you find several fruiting bodies of one type of fungus growing on the ground, see if you can follow around in a circle and locate any more. The size of the circle will give you some indication of the size of the mycelium hidden beneath your feet. Bear in mind when you do this, that the fungus which is fruiting, will not be the only fungus hidden down there in the soil. In fact the ground beneath your feet will be absolutely seething with the mycelia of different fungi. We remain totally unaware of their presence simply because we can't see them.
The main body of most fungi is made up of fine, branching, usually colourless threads called hyphae. Each fungus will have vast numbers of these hyphae, all intertwining to make up a tangled web called the mycelium.
The mycelium is generally too fine to be seen by the naked eye, except where the hyphae are very closely packed together. The picture on the left was taken through a microscope. The hyphae are magnified 100 times life size.
.
Some fungi, such as Honey Fungus, which is a parasite of woodland trees, have hyphae collected together into long cables, called rhizomorphs. Because there are so many hyphae packed together, they are easily seen, forming black 'bootlaces'. These can spread through a woodland infecting neighboring trees.
Fungal mycelium is mostly hidden from human view, not only because of its small size, but also as a result of its location. The tangled mycelial mass is usually hidden deep within its food sources, such as rotting matter in the soil, leaf litter, rotting wood, or dead animals. The mycelium remains undetected until it develops one or more fruiting bodies, containing the reproductive spores.
Fruiting bodies (such as mushrooms) are made up of thick collections of hyphae. They vary in size from small and insignificant, to large eye-catching structures.
They are usually produced at the surface of the food source, rather than hidden within it, to allow the spores to be shed and carried away by the wind, or by water, or animals. The fruiting bodies are usually the only indication we have that a fungus is present. Like icebergs, they represent a tiny fraction of the whole fungus, with most of it being hidden from view.
If you are looking for fungi in Britain, the best time to look is in the autumn. The fungal mycelia have then had a long, relatively warm period to grow extensively over the summer. With the coming of wetter weather in the autumn, damp warm conditions are created which are ideal for fungi to fruit. Many fungi have fruiting seasons in late summer to autumn. However, don't ignore the Spring. This is a good time to look for fungi such as Morels and other cup fungi. Little will be found in cold winter months with frosts, although Oyster mushrooms will continue to grow through most of the winter, as will Jew's Ear.
Fairy Rings
Fungal mycelia tend to grow in more or less circular shapes. This is because they grow by spreading out in all directions from a central point. This central point represents the location of the original spore which germinated to start the fungal mycelium. The mycelium will usually produce fruiting bodies on its outer edge. As a result, the fruiting bodies of fungi living hidden in the soil can sometimes be found in rings - the 'fairy rings' of children's stories.
The Clouded Agaric toadstool (right) is a good example of this. The fruiting bodies can often be found in rings, because they are produced on the outer growing edge of the circular, underground mycelium. The Clouded Agaric can be found in the leaf litter of both coniferous and deciduous woodland.
(image courtesy of Jeff Benn)
Another example is the 'Fairy Ring Toadstool' (Its scientific name is Marasmius oreades). This, in contrast to the Clouded Agaric, grows on grassy expanses such as lawns and golf courses. The fungus can be traced by the rings of dark green grass, with the mushrooms fruiting on the outer edge of the ring. The growth of the ring can be traced year on year. If there are no barriers, rings may grow outwards at up to 20 cm per year. This is a fungus which fruits early in the year, in the spring.
Giants of the natural world
Most people, if asked to name the largest organism on earth, come up with examples such as elephants, blue whales or giant trees, such as Redwoods. In fact, the largest living organism on this planet may well be a fungus!
In America, a single individual fungus, similar to the Honey Fungus already mentioned, was found to cover a staggering 2,200 acres of land. (This is 45 times bigger than the Woodland Education Centre in Offwell, for those of you who have visited the Centre before.)
Some of the oldest living organisms?
We tend to think of fungi as being short-lived, because the visible fruiting bodies which we see don't usually last very long. However, for the fungus to have reached this size, it must have been at least 2,400 years old. It would have been a mere youngster of 400 years old, at the time of Christ's birth.
The rings of Fairy Ring Toadstools found closer to home in Britain, possibly on your back lawn, can also grow to hundreds of meters in diameter, when they are likely to be at least a thousand years old.
Some lichens, which are a partnership between a fungus and an alga, have been estimated to be around 9000 years old!
Next time you find several fruiting bodies of one type of fungus growing on the ground, see if you can follow around in a circle and locate any more. The size of the circle will give you some indication of the size of the mycelium hidden beneath your feet. Bear in mind when you do this, that the fungus which is fruiting, will not be the only fungus hidden down there in the soil. In fact the ground beneath your feet will be absolutely seething with the mycelia of different fungi. We remain totally unaware of their presence simply because we can't see them.
NEW FORM OF FUNGI
It's that time of year! Everything is coming up green, which means it's time to start planning your outdoor growing projects. Growing mushrooms on logs and stumps with our Mushroom Plug Spawn can be a great standalone project, or as a complement to any garden or landscape!
Our Outdoor Mushroom Patches™ are another great option for mushroom cultivation at home. We offer a wide variety of mushroom species (such as our Garden Giant Mushroom Patch™, pictured at right) for cultivation in beds of wood chips, soil or other material in your yard or garden.
2009 Seminar Dates Announced! We've put together our schedule of 2009 Cultivation and Mycorestorationsm Seminars and have made them available for signup. These classes will fill up fast—2008 is alread booked solid—so don't delay!
Our Outdoor Mushroom Patches™ are another great option for mushroom cultivation at home. We offer a wide variety of mushroom species (such as our Garden Giant Mushroom Patch™, pictured at right) for cultivation in beds of wood chips, soil or other material in your yard or garden.
2009 Seminar Dates Announced! We've put together our schedule of 2009 Cultivation and Mycorestorationsm Seminars and have made them available for signup. These classes will fill up fast—2008 is alread booked solid—so don't delay!
BACTERIA DRIVE AND MULTIPLY
Bacteria are all around us. Given good growing conditions, a bacterium grows slightly in size or length, a new cell wall grows through the center forming two daughter cells, each with the same genetic material as the parent cell. If the environment is optimum, the two daughter cells may divide into four in 20 minutes. Oh my! 1, 2, 4, 8, 16, 32, 64... Then why isn't the earth covered with bacteria?
The primary reason may be that conditions are rarely optimum. Scientists who study bacteria try to create the optimum environment in the lab: culture medium with the necessary energy source, nutrients, pH, and temperature, in which bacteria grow predictably.
LAG PHASE: Growth is slow at first, while the "bugs" acclimate to the food and nutrients in their new habitat.
LOG PHASE: Once the metabolic machinery is running, they start multiplying exponentially, doubling in number every few minutes.
STATIONARY PHASE: As more and more bugs are competing for dwindling food and nutrients, booming growth stops and the number of bacteria stabilizes.
DEATH PHASE: Toxic waste products build up, food is depleted and the bugs begin to die.
View a 520K time-lapse movie to see how two E. coli, given a suitable environment for growth, divide and form a colony of hundreds of bacteria in just a few hours. Or visit the CELLS alive! BioCam to see bacteria colony in "real time". A longer, larger, silent version of growing E. coli may be purchased and downloaded for classroom use.
Some Keywords:
exponential growth, binary fission, asexual reproduction, population dynamics, lag phase, log phase, stationary phase, death phase
The primary reason may be that conditions are rarely optimum. Scientists who study bacteria try to create the optimum environment in the lab: culture medium with the necessary energy source, nutrients, pH, and temperature, in which bacteria grow predictably.
LAG PHASE: Growth is slow at first, while the "bugs" acclimate to the food and nutrients in their new habitat.
LOG PHASE: Once the metabolic machinery is running, they start multiplying exponentially, doubling in number every few minutes.
STATIONARY PHASE: As more and more bugs are competing for dwindling food and nutrients, booming growth stops and the number of bacteria stabilizes.
DEATH PHASE: Toxic waste products build up, food is depleted and the bugs begin to die.
View a 520K time-lapse movie to see how two E. coli, given a suitable environment for growth, divide and form a colony of hundreds of bacteria in just a few hours. Or visit the CELLS alive! BioCam to see bacteria colony in "real time". A longer, larger, silent version of growing E. coli may be purchased and downloaded for classroom use.
Some Keywords:
exponential growth, binary fission, asexual reproduction, population dynamics, lag phase, log phase, stationary phase, death phase
NATURAL FUNGUS KINGDOM
The Fungus Kingdom
(Last modified: 3 Jan 2002)
In addition to the beauty of mushrooms, fungi provide a critical part of nature's continuous rebirth: fungi recycle dead organic matter into useful nutrients. Sometimes the fungus doesn't wait for the biomatter to die, in which case the fungus is called a parasite. Many plants, however, are dependent on the help of a fungus to get their own nutrients, living in a symbiotic relationship called a mycorrhizal association. Plants aren't the only ones, however, to enjoy fungi.
Fungi digest food outside their bodies: they release enzymes into the surrounding environment, breaking down organic matter into a form the fungus can absorb. Mycorrhizal associates benefit from this by absorbing materials digested by the fungi growing among their roots.
Fungi reproduce by releasing spores from a fruiting body. The fruit, called a mushroom, releases spores into the air, and the wind carries the spores off to start the next generation. Around 100,000 species of fungi are divided into five phyla, based largely on the characteristics of their reproductive organs.
Club Fungi (Basidiomycota)
When people think of mushrooms, the fruit of Basidiomycota probably comes to mind. Many mushrooms in this phylum look like umbrellas growing from the ground or like shelves growing on wood, but some, such as the latticed stinkhorn, look quite different.
Among the more famous families in this phylum are Agaricus -- including the supermarket variety of button mushrooms; Amanita -- including species that are deadly, delicious, or even hallucinogenic; Boletus -- best known for the King Bolete (called Porcini in Italy and Cepe in France); and Cantherellus -- known for the delicious and beautiful Chanterelle. These families include but a few of the mushrooms sought by collectors and gourmets from among the 25,000 species in this phylum.
Species in this phylum produce spores on a club-like structure called the basidium. The basidium may grow free or be attached to a surface called the hymenium.
Class: Homobasidiomycetae produce spores on a hymenium.
Subclass: Hymenomycetes
Produce spores on exposed surfaces -- releasing the spores gradually through structures such as pores or gills.
Orders: Agaricales, Aphyllophorales (3 examples)
Subclass: Gasteromycetes
Produce spores on concealed surfaces, releasing spores only after the cover ruptures. Pictured below are a puffball and earthstar of the Order Lycoperdales and two stinkhorns of the Phalales Order.
Class: Heterobasidiomcetae
Produce spores on the ends of inconspicuous threads. Examples include: jelly fungi (pictured), rusts, smuts
Sac Fungi (Ascomycota)
Ascomycota produce their spores in special pods or sac-like structures called asci. Included among the 25,000 species of this phylum are the prized Morel and Truffle mushrooms (class: Euascomycetae).
Other member of this class include Elfin Saddles (above/left), Morels, Cup Fungi, and Flask Fungi (below, left-to-right)
Another class of this phylum, Hemiascomycetae, is valued more for its activity than its beauty. Sacharomyces cerevisiae (Brewers, Bakers, and Nutritional Yeast) help us produce such popular staples as beer and bread.
Other Classes: Loculoascomycetae, Laboulbeniomycetae
Lichens (Mycophycophyta)
Once the beauty of mushrooms has enticed your greater scrutiny of the forest floor, you can't help but notice lichens as well.
Lichens are a symbiotic union between fungus and algae (or sometimes photosynthesizing bacteria). The algae provide nutrients while the fungus protects them from the elements. The result is a new organism distinctly different from its component species.
Though no longer considered a proper phylum, the radically different nature of these symbiots warrants separate treatment in this overview of the fungus kingdom.
Around 25,000 species of Lichens have been identified by scientists.
Conjugation Fungi (Zygomycota)
The best known of this phylum of around 600 species is black bread mold, such as Rhizopus stolonifer.
Imperfect Fungi (Deuteromycota)
Around 25,000 additional fungus species are grouped in this phylum -- these species are the "left-overs" that don't fit well into any of the other groups. Members include Trichophyton (Athlete's foot), Penicillium (Penicillin), and Candida albicans ("Yeast" infections).
Page 7 of 38
--------------------------------------------------------------------------------
Annotated Bibliography
Arora, David, Mushrooms Demystified (2nd edition), Ten Speed Press, Berkeley, 1986
This is the authoritative field guide to mushrooms of the Western United States. The book provides thorough keys for identifying mushrooms, as well as lively anecdotes and related information for the amateur and expert alike.
Alexopoulos, Constantine J., C. W. Mims, M. Blackwell, Introductory Mycology, (4th edition), John Wiley & Sons, New York, 1996
A college-level text on the world of fungi, organized according to the principles of classification.
Margulis, Lynn, Karlene Schwartz, Five Kingdoms: An Illustrated Guide to the Phyla of Life on Earth (2nd edition), W. H. Freeman and Company, New York, 1988
An overview of the highest levels of Taxonomy. I have used the authors' nomenclature where available. Names, however, are constantly changing in the field of Taxonomy, and no doubt many of these names are disputed or have changed since 1988.
Margulis, Lynn, Diversity of Life: The Five Kingdoms, Enslow Publishers, Inc., New Jersey, 1992
Although billed as a children's book, this book is quite appropriate for the adult amateur. Dr. Margulis strikes an excellent balance between detail and brevity in this fact-filled book.
Milani, Jean P., et. al. Biological Science: An Ecological Approach (6th edition), Kendall/Hunt Publishing Company, Iowa, 1987
A high school textbook that devotes several chapters to Taxonomy and the diversity of life on our planet. The Appendix titled A Catalog of Living Things illustrates the phyla as well as many classes and families within the five kingdoms.
(Last modified: 3 Jan 2002)
In addition to the beauty of mushrooms, fungi provide a critical part of nature's continuous rebirth: fungi recycle dead organic matter into useful nutrients. Sometimes the fungus doesn't wait for the biomatter to die, in which case the fungus is called a parasite. Many plants, however, are dependent on the help of a fungus to get their own nutrients, living in a symbiotic relationship called a mycorrhizal association. Plants aren't the only ones, however, to enjoy fungi.
Fungi digest food outside their bodies: they release enzymes into the surrounding environment, breaking down organic matter into a form the fungus can absorb. Mycorrhizal associates benefit from this by absorbing materials digested by the fungi growing among their roots.
Fungi reproduce by releasing spores from a fruiting body. The fruit, called a mushroom, releases spores into the air, and the wind carries the spores off to start the next generation. Around 100,000 species of fungi are divided into five phyla, based largely on the characteristics of their reproductive organs.
Club Fungi (Basidiomycota)
When people think of mushrooms, the fruit of Basidiomycota probably comes to mind. Many mushrooms in this phylum look like umbrellas growing from the ground or like shelves growing on wood, but some, such as the latticed stinkhorn, look quite different.
Among the more famous families in this phylum are Agaricus -- including the supermarket variety of button mushrooms; Amanita -- including species that are deadly, delicious, or even hallucinogenic; Boletus -- best known for the King Bolete (called Porcini in Italy and Cepe in France); and Cantherellus -- known for the delicious and beautiful Chanterelle. These families include but a few of the mushrooms sought by collectors and gourmets from among the 25,000 species in this phylum.
Species in this phylum produce spores on a club-like structure called the basidium. The basidium may grow free or be attached to a surface called the hymenium.
Class: Homobasidiomycetae produce spores on a hymenium.
Subclass: Hymenomycetes
Produce spores on exposed surfaces -- releasing the spores gradually through structures such as pores or gills.
Orders: Agaricales, Aphyllophorales (3 examples)
Subclass: Gasteromycetes
Produce spores on concealed surfaces, releasing spores only after the cover ruptures. Pictured below are a puffball and earthstar of the Order Lycoperdales and two stinkhorns of the Phalales Order.
Class: Heterobasidiomcetae
Produce spores on the ends of inconspicuous threads. Examples include: jelly fungi (pictured), rusts, smuts
Sac Fungi (Ascomycota)
Ascomycota produce their spores in special pods or sac-like structures called asci. Included among the 25,000 species of this phylum are the prized Morel and Truffle mushrooms (class: Euascomycetae).
Other member of this class include Elfin Saddles (above/left), Morels, Cup Fungi, and Flask Fungi (below, left-to-right)
Another class of this phylum, Hemiascomycetae, is valued more for its activity than its beauty. Sacharomyces cerevisiae (Brewers, Bakers, and Nutritional Yeast) help us produce such popular staples as beer and bread.
Other Classes: Loculoascomycetae, Laboulbeniomycetae
Lichens (Mycophycophyta)
Once the beauty of mushrooms has enticed your greater scrutiny of the forest floor, you can't help but notice lichens as well.
Lichens are a symbiotic union between fungus and algae (or sometimes photosynthesizing bacteria). The algae provide nutrients while the fungus protects them from the elements. The result is a new organism distinctly different from its component species.
Though no longer considered a proper phylum, the radically different nature of these symbiots warrants separate treatment in this overview of the fungus kingdom.
Around 25,000 species of Lichens have been identified by scientists.
Conjugation Fungi (Zygomycota)
The best known of this phylum of around 600 species is black bread mold, such as Rhizopus stolonifer.
Imperfect Fungi (Deuteromycota)
Around 25,000 additional fungus species are grouped in this phylum -- these species are the "left-overs" that don't fit well into any of the other groups. Members include Trichophyton (Athlete's foot), Penicillium (Penicillin), and Candida albicans ("Yeast" infections).
Page 7 of 38
--------------------------------------------------------------------------------
Annotated Bibliography
Arora, David, Mushrooms Demystified (2nd edition), Ten Speed Press, Berkeley, 1986
This is the authoritative field guide to mushrooms of the Western United States. The book provides thorough keys for identifying mushrooms, as well as lively anecdotes and related information for the amateur and expert alike.
Alexopoulos, Constantine J., C. W. Mims, M. Blackwell, Introductory Mycology, (4th edition), John Wiley & Sons, New York, 1996
A college-level text on the world of fungi, organized according to the principles of classification.
Margulis, Lynn, Karlene Schwartz, Five Kingdoms: An Illustrated Guide to the Phyla of Life on Earth (2nd edition), W. H. Freeman and Company, New York, 1988
An overview of the highest levels of Taxonomy. I have used the authors' nomenclature where available. Names, however, are constantly changing in the field of Taxonomy, and no doubt many of these names are disputed or have changed since 1988.
Margulis, Lynn, Diversity of Life: The Five Kingdoms, Enslow Publishers, Inc., New Jersey, 1992
Although billed as a children's book, this book is quite appropriate for the adult amateur. Dr. Margulis strikes an excellent balance between detail and brevity in this fact-filled book.
Milani, Jean P., et. al. Biological Science: An Ecological Approach (6th edition), Kendall/Hunt Publishing Company, Iowa, 1987
A high school textbook that devotes several chapters to Taxonomy and the diversity of life on our planet. The Appendix titled A Catalog of Living Things illustrates the phyla as well as many classes and families within the five kingdoms.
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