The Amazing World Of Mushrooms And Other Fungi
The Amazing Fungi
Did you know that there are over 100,000 described fungi species? Some of them are very poisonous and a small bite will mean death. Some fungi glow in the dark. A few fungi are unicellular. Yeast is a great example of a unicellular fungi. Most fungi, for example mushrooms, are multicellular. Fungi are more related to you and I than they are to plants. Fungi are ecologically important as they are our environment's decomposers. They also form necessary, symbiotic relationships with plants. Lets learn a little more about fungi, what they are, why they are important, and some of the things that make fungi so interesting.
What do fungi eat?
Fungi are heterotrophs or chemoheterotrophs. This means that they do not make their own food. Fungi must get energy from outside sources. Some fungi are saprophytic, meaning that they get their nutrition from dead or decaying sources. Other fungi are decomposers, breaking down what was once intact material. Lastly, a few fungi are parasitic, living off of live hosts, and cause disease.
Fungi Body Structure
Fungi are made out of chitin. This is the same material that rhinoceros horns and fingernails are made out of. It is much different from the structural materials that plants use. This is one of the reasons that fungi are more related to animals than plants.
When you think of a fungi you likely envision a mushroom. The mushroom is only a small part of a fungus known as the fruiting body. The fruiting body has that name because it is similar to a plant's fruit. The fruiting body is a reproductive structure. It contains spores that will become the next generation of fungi. Not all fungi will have a fruiting body. Yeasts are unicellular and do not have this type of structure.
The majority of the fungal body is the part we can't see. It is called mycelium. The mycelium consists of multiple hyphae. (Coenocytic fungi don't have hyphae but other fungi do.) The hyphae resemble tree roots. They are a huge network of webbed branches. The hyphae break down food sources and take in nutrition. This is why scraping mold off of moldy food doesn't work well. The visible portion of the mold, the fruiting body, is only a tiny part of the problem. You are not removing most of the mold's body. The hyphae will remain in the food where you can't see them. They carry with them the same toxins as the full fungi. They also will still cause food to have a bad taste.
If you would like to see some fungi spores, go to the grocery store and buy some mushrooms. Take the stem off of the cap (top) of the mushroom. You will see gills on the bottom side of the mushroom cap. These hold thousands of spores. Get a piece of paper out. Set the mushroom cap on the paper with the gills down. Sit a cup over the mushroom so it isn't disturbed. Check the paper after 24 hours. You should have a spore print. People who gather wild mushrooms will actually use this print to identify mushroom species from each other.
Fungal ancestors are actually single celled, flagellated protists. These eventually developed into the organisms that we are now familiar with. Fungi are actually more closely related to humans than plants!
Fungi may reproduce sexually or asexually. Some fungi reproduce using spores. Spores are useful because they are very hardy. They also can spread genetic material over large distances.
In sexual reproduction the fungus will signal that it is ready to mate using pheromones. The fungi will then join their hyphae. The two sets of hyphae join together and exchange genetic information. After a while the fruiting body will appear and produce spores. These spores will disseminate and plant new fungi.
About 20,000 fungi species use only asexual reproduction. These fungi may bud off (yeasts) or use mitosis.
Part Of The Mushroom Lifecycle
If you would like your garden, trees, or shrubs to have a little boost, buy some mycorrhizae. You can find them at most plant stores. Add them to the hole when you plant or dig a hole near the plant's roots. Your garden will thank you!
Special Relationships With Plants
When you dig up a plant, you will see roots... and fungi! Part of what appears to be a plant's root structure is actually specialized fungal hyphae called haustoria. These hyphae help to convey water and nutrients into the plant. Both woody (trees) and non-woody (flowers) plants have this mutualism with fungi. Different fungal species will pair up with different plants. (This is why you will see certain mushroom types grow only under certain tree species. They have a mychorrizal relationship with the tree.) Almost all vascular plants have mycorrhizae.
Examples Of Fungi
- common in lakes and soils
- amphibian parasite
- killing off thousands of frogs
- bread mold
- sexual and asexual reproduction
- can aim their spores in certain directions
- Lives with 90% of plants
- mycorrhizal relationships with plants
- 65,000 species
- the most common type of fungi
- lichens and most mushrooms are in the group
- important decomposers
- 30,000 species
- second most common fungi
- morel mushrooms and truffles