Introduction: (Initial Observation)
Mushroom is a fungus that has many different varieties. Some are edible and some have medicinal properties. Finally some mushrooms are poisonous.
The world market of edible mushrooms has been estimated at 3-6 billion US$.
Species of mushrooms that are edible are fairly rich in vitamin B2 and niacin and also in copper. Raw mushrooms have only 10 calories per half cup and contain some protein.
Although mushroom grows naturally, most mushrooms that we buy for food are produced in a controlled environment by mushroom producers. Like in any other production, mushroom producers constantly try to discover ways of increasing the quality and the amount of their products. To optimize the production of mushroom we need to know the conditions favorable for mushroom production.
Adult supervision is required for the experiments of this project. You must perform at least one of the three proposed experiments or any similar experiment to test your hypothesis.
Information Gathering:
Find out about a mushroom and its reproduction methods. Read books, magazines or ask professionals who might know in order to learn about the best conditions for mushroom growth. Keep track of where you got your information from. The following are a sample of information that you may find.
Mushrooms (fungi) reproduce asexually, needing the spores from only one parent to reproduce
Facts:
-
- Mushrooms are not plants, they are from a different kingdom called fungi.
- A fungus does not have chlorophyll, as plants do.
- Other fungi you may already know are molds, mildews, and yeasts.
- Mushrooms are saprophytes (An organism that lives on dead or decaying material) and, often, parasites (A plant or organism that lives in or on another plant or organism).
- Mushroom-producing fungi are not plants. They have no chlorophyll and can’t make their own food directly from sunlight. They do consume both live and dead plants for food.
- Many fungi live in symbiosis with other organisms, such as algae (lichens), plant roots (mycorrhizae), or insects such as ants.
- Instead of seeds, mushrooms have spores that drop to the ground from their gills (The thin, leaf like radiating plates on the undersurface of a mushroom).
- When the spores land on the ground they sprout mycelia the same way a plant seed sprouts roots.
Gathering Spores Experiment
Materials:
-
- 1 fresh mushroom (either store bought or picked)
- 1 glass cup or bowl large enough to fit over the mushroom
- 1 sheet of plain white paper
- Clear acrylic spray (only if you want to save the experiment design) *optional
Safety Precautions:
Some mushrooms are poisonous! If you picked the mushroom outside, do not eat it.
Procedure:
-
- Get a mushroom, a piece of white paper, and a cup.
- Break off the mushroom stem so that the cap can be laid down fairly flat.
- Lay the mushroom gill-side-down on the piece of paper.
- Carefully cover the mushroom cap with the open end of the glass or bowl.
- Let the mushroom sit for at least an hour, preferably overnight.
- GENTLY lift the glass or bowl from the mushroom and VERY GENTLY lift the mushroom cap from the paper. You should see a beautiful radial design.
- If you want to save the design, spray the paper with clear acrylic.
Vocabulary
ASEXUAL
Showing no sexual differentiation (no male or female forms)
CHLOROPHYLL
The green matter in plants. In the presence of sunlight, it converts carbon dioxide and water into carbohydrates that feed the plant
FUNGI (singular: fungus)
One of the five kingdoms of life (animals, plants, fungi, protists, and monerans). Fungi were once thought to be plants but they have no chlorophyll and cannot make their own food. Instead, they dissolve and then absorb food.
GILLS
The thin, leaflike radiating plates on the undersurface of a mushroom
MYCELIA (singular: mycelium)
The vegetative part of a fungus made up of threadlike tubes
PARASITE
A plant or organism that lives in or on another plant or organism
SAPROPHYTE
An organism that lives on dead or decaying material
SPORE
A small reproductive body, often consisting of a single cell, produced either asexually or sexually. They are highly resistant to environmental damage and are capable of giving rise to a new adult individual, either immediately or after an interval of dormancy.
Mushroom Reproduction
Mushrooms can be reproduced from spores and tissue culture.
Mushroom reproduction by Spores:
To collect the spores, sever the cap from the stem of a fresh, cleaned mushroom. Place the cap, or portion of the cap, gill side down on a piece of white paper or a clean microscope slide. To minimize evaporation and disturbance from air currents, place a beaker or Petri dish over the cap. After several hours, a spore print will be present. If you have made the print on paper, cut it out, fold it in half, seal it in an air-tight container and label the specimen. If the print was made on a microscope slide, place another slide over the spores and seal the edges with tape to prevent contamination. These methods will allow you to store the spore prints until you are ready to culture. A quick way to establish cultures from basidiocarps (reproductive bodies) using spores is to attach a small piece of the cap (with gills) to the inside lid of a Petri dish of agar medium using petroleum jelly. Place the dish on a slant so that the spores are showered down across the agar inside of massed up in a spore print. This makes it easier to transfer spores, and the spores are more likely to germinate than if they are in a mass.
To culture from spores, sterilize an inoculating loop or other transfer tool. Scrape some spores off the spore print and streak across the surface of agar medium (potato sucrose agar, rabbit food agar). When starting a new culture from spores, it is best to inoculate at least three media dishes to improve the chances of getting successful germination.
In general, fresh mushrooms will yield the best spores for germinating. However, if you are using an older mushroom, or an older spore print, it may still be possible to germinate the spores if they are rehydrated first. Spores can be soaked in sterilized water to rehydrate them. Scrape the spores from the spore print and transfer to a sterile test tube filled with sterile distilled water. Seal the tube and let stand for 6-12 hours. Draw up several ml of spore suspension with a sterile pipette and inoculate several plates with one or two drops of suspension.
Not all spores will germinate, and others will have very poor germination. For those that do not germinate readily,
1. A range of media with vegetable or fruit extracts have been useful in inducing spore germination. Chick-pea agar and prune agar are also recommended.
2. Many mushrooms require gut enzymes to induce germination. Treatment of the spores by washing in an aqueous solution of pancreatin has been shown to be useful in inducing germination in some fungi.
Mushroom reproduction by Tissue Culture:
Tissue cultures must be taken from mushrooms within 24-48 hours after collection. If the specimens are too old or too mature, a pure culture will be extremely difficult to isolate.
Since the entire mushroom is composed of compressed mycelia, a culture can be obtained from any part of the mushroom. The cap, the upper region of the stem and the area where the gill plate joins the underside of the cap are the best locations for excising tissue free of contaminants. The stem is often colonized by maggots and other insects, which bring with them their own set of contaminating microorganisms.
It may be possible with some specimens to peel back the ‘skin’ (cuticle) from the upper surface of the cap and obtain clean tissue from the underlying flesh. This is particularly true with specimens of Suillus, Gomphidius, and other mushrooms with slimy cuticles. Wipe the surface of the mushroom with a cotton swab soaked in 70% ethyl alcohol and remove any dirt or damaged tissue. Break the cap or stem, exposing the internal tissue. Working quickly to reduce chances of contamination, remove a small piece of tissue and transfer to the center of an appropriate medium. Do at least five transfers in this manner. If successful, growth should be present in 3-7 days.
Mushroom Production
There are many different types of mushrooms produced in the world, but the most widely produced mushroom is known as white button mushroom with a scientific name of Agaricus bisporus.
Introduction
Successful mushroom growing involves overcoming difficulties such as temperature and humidity control, pest control and compost preparation. The amateur mushroom grower should recognize that most basements do not provide ideal conditions for good growth.
Mushroom production is a difficult task at the best of times. This information is intended to provide useful tips in order to increase the rate of success of growing mushrooms.
Location
For the amateur, mushrooms are usually planted in the fall and the best location is the cellar, basement, or a barn or any tight, light-proof, well ventilated and insulated building. The following conditions should be met:
Air temperatures controlled between 13°C and 21°C.
Relative humidity between 80-95 %.
A corner of the basement can be partitioned off by the use of a polyethylene divider. This will help to maintain proper humidity levels. A plastic hood placed over the growing bed is a second alternative. Do not place beds where direct sunlight will fall on them. Ventilation is useful to remove offensive odors. Where temperatures cannot be maintained, supplementary heat is necessary.
Mushroom beds are usually 120-150 cm wide, 15-20 cm deep and as long as you wish. Boards that form the bottom should not be over 15-20 cm wide, leaving 2 cm to 4 cm cracks between them for ventilation. Several tiers can be made approximately 60 cm apart. Production in plastic bag beds is also used commercially especially in Europe.
Compost Preparation
The growing medium for mushrooms is a compost which traditionally has been made from horse manure, hay, poultry manure, brewer’s grain, gypsum and commercial fertilizers, including ammonium nitrate.
A suggested formula for trial use is as follows:
horse manure (85%) .75m³
hay (10%) .5-1 bale
poultry manure (5%) 18 L
gypsum 4.5 kg
ammonium nitrate .45 kg
This formula will supply sufficient compost to fill a growing bed with the following dimensions: 300 cm long, 120 cm wide and 15 cm deep, or .57m³. A growing bed 20 cm deep is more satisfactory.
To prepare the compost, start with a layer of manure on the bottom and alternate with a layer of hay, poultry manure and fertilizer materials. If possible, the horse manure should be piled under cover and the pile should be square and the top level. Wet the pile thoroughly during layering and throughout the 12-14 day composting period. Turn the pile on the third day, mixing the ingredients thoroughly, add water to run-off and repeat the turning process on the 6th, 9th and 12th days.
If there is enough moisture, oxygen and nitrogen, the temperatures within the pile should rise to 60°C-66°C. At the end of the composting period, the compost should be dark brown, pliable and lumps should break apart easily. The compost is now ready for the beds. Hobby mushrooms growers report some success using straight, fresh horse manure obtained from horse stables with no other additives. The horse manure is then composted for 10-14 days, steam pasteurized for 30 minutes at an estimated 71°C, allowed to aerate sufficiently to remove all traces of ammonia odor and placed into beds. Steam pasteurization is required for the control of insects and diseases that are present in the compost.
Production Steps – Spawning
Allow the compost to remain in the beds until the temperature of the compost drops to 21-27°C before applying the spawn. Ammonia odor in the beds will usually kill the spawn. The compost bed should be mounded up firm, but not packed. Spawn should be broadcast over the surface of the bed and mixed thoroughly into the compost. Apply the spawn at the rate recommended by the supplier. Spawn is available in small packages from seed companies and garden supply centers. Maintain the bed temperature at 21°C-25°C for 1 week then lower the temperature to 15°C-18°C for the remainder of the production period. Spawn will be killed at 35°C. Examine the spawn run in the bed after 2 to 3 week. Casing should be applied when the white cottony growth of the fungus has reached the top of the bed. Remember to keep the compost moist at all times. It is good to cover the bed surface with newspaper or plastic. Keep the newspaper wet. Very little fresh air is required during the spawn run.
Pest control
The two most common pests that are likely to occur are:
_ Fungus gnat (fly) larvae, and
_ Fungal diseases
Fungus gnat larvae may be controlled by hanging insecticide strips. Several insecticides may be used as thermal fogs. For details consult your local mushroom specialist. Fungicides may be used for disease control. Apply only if disease problems have been encountered and only after casing. If necessary, a second application can be made up to the first pinning. Consult label recommendations for days to harvest. Use a small pressurized sprayer or a watering can with a fine nozzle. (Yellow sticky traps can be used to monitor fly levels.)
Casing
A convenient casing material contains equal parts by weight of sphagnum peat moss and calcitic limestone. Prewetting of the casing material is advisable. Commercially prepared casing material to which lime must be added is available in some areas. The moist casing layer is placed over the surface of the compost bed to a depth of 2-4 cm.
Cropping
First mushrooms should appear 3-4 weeks after casing. Regular watering to keep the casing soil moist will encourage mushroom growth and help to keep the humidity high.
Sprinkle frequently with warm water but do not overwater. Good ventilation is important when the pins, (small mushrooms) begin to develop. A mushroom is ready to be picked when the diameter of the cap is equal to the length of the stem and preferably before the veil under the cap stretches and opens. Mushrooms are twisted out rather than pulled. Good commercial yields often reach 1.4 kg per m².
Another Mushroom growing guide:
The process of growing mushrooms can be divided roughly into four steps:
1) Acquiring and maintaining a culture of mushroom tissue (called mycelium) of the mushroom strain you want. (A tissue culture is somewhat like a cutting of a plant. Starting with a tissue culture assures that you have a mushroom strain genetically identical to the one you want. Some growers start with spores, which are more like seeds. Spores may or may not give you a mushroom strain with the fruiting properties of the parent. Since spores cannot be grown in the presence of hydrogen peroxide, I always work with a tissue culture of mycelium. Tissue cultures–also called agar cultures or test tube cultures–of various species of mushroom can be purchased from commercial suppliers or they can be started from fresh mushrooms).
2) Using a bit of the tissue culture to begin some spawn (a kind of mushroom starter), which is usually grown on a small quantity of sterilized grain or sawdust.
3) Using the spawn to introduce mushroom mycelium into an organic material (substrate) chosen to support the formation of mushrooms.
4) Getting the actual mushrooms to form and grow once the substrate has been completely colonized by mushroom mycelium.
Starting with a kit
If you buy a mushroom kit, you are generally starting at step four. The commercial mushroom grower has already completed the earlier steps for you, and provided you with the mushroom culture ready to form mushrooms. You provide a proper environment, usually cool and moist. Getting mushrooms to form can be easy or hard, depending on the mushroom strain you are growing. Oyster-style mushrooms of the Pleurotus and Hypsizygus families are among the easiest to fruit. Lions Mane (Hericium erinaceus) is also quite easy. Maitake (Grifola frondosa) and Morels (Morachella species) are among the most difficult to get to form mushrooms. Shiitake (Lentinula edodes) falls somewhere in the middle. Button mushrooms are easy if you can keep the temperature steady around 65 degrees F.
Starting with purchased spawn
It is also possible to start at step three, by purchasing the “starter” (spawn) from a supplier and using that to introduce the growing fungus into an organic material that you have prepared yourself. There are a variety of possible substrates: straw, compost, logs, wood chips, and sawdust are common ones, but people have also used things like newspaper, cardboard, sterilized grain, coffee grounds, etc. depending on the mushroom species they want to grow.
Kinds of mushrooms and the substrates they prefer
In general, there are two broad classes of cultivated mushrooms: those that prefer to grow on compost, and those that prefer to grow on woody material. The common button mushroom and other Agaricus species fall into the first class, growing readily on compost, but they will also grow on straw. Oyster mushrooms, shiitake, reishi, maitake, and Lions Mane, all prefer woody materials such as sawdust, wood chips, or sometimes straw.
Compost
Each organic material requires a different procedure to render it free of competing organisms. Compost is the most time-consuming material to prepare, requiring a couple of weeks to mature. It needs to be allowed to heat to a temperature that neutralizes harmful species, without letting it get so hot that it kills beneficial microbes. The compost is not allowed to go completely through its natural cycle. Instead it is harvested somewhat early, when it is full of white actinomycetes bacteria that provide the nutrients that mushrooms love. The grower cools the compost, adds some gypsum (calcium sulfate) and mixes in the mushroom spawn.
Woody materials
Woody materials and straw can be prepared much more quickly than compost. Traditionally, these materials required a heat treatment, such as pressure sterilization, steam pasteurization, or hot water steeping, to eliminate competing organisms. The peroxide method has now added ways to prepare some substrates without heating. It can also prevent later contamination by airborne molds and bacteria, so using a material that is compatible with hydrogen peroxide addition can save a lot of trouble. For wood-decomposing mushrooms, wood pellet fuel, which disintegrates into sawdust when treated with boiling water, works very well in this regard, and so does wheat straw.
Getting Mushrooms to Form
The compost-loving species require a different procedure from the wood-loving mushrooms when it comes time to get the mushrooms to form. The compost-lovers usually need to have a soil-like layer called “casing,” applied to the top of the culture, once the mushroom tissue has fully colonized the compost. The soil-like layer provides a reservoir of moisture, and it creates a low-nutrient zone (compared to the compost), signaling the mushroom tissue to start forming the fruiting bodies. The tiny mushroom buttons then begin to form in the casing layer. The grower keeps the casing moist by lightly watering it as the mushrooms enlarge.
With wood-loving species, the procedure for getting mushrooms to form varies a bit from one species to another, but it usually involves a shift in environmental conditions such as a drop in temperature, an increase in air circulation, and/or an increase in light levels.
The whole nine yards?
Once you have tried growing mushrooms from a kit and from spawn you’ve purchased, you will have a better idea whether you want to get involved in keeping agar cultures and growing your own spawn. These procedures require somewhat more commitment and attention to detail. Before the invention of the peroxide technique, it was generally only possible to keep agar cultures and grow spawn if you constructed a sterile work space, such as a glove box at the very least. With peroxide, it becomes possible to perform these steps in an ordinary kitchen, and grow the cultures just about anywhere that an appropriate temperature and light level can be provided. You still need to learn some basic “sterile technique”–simple procedures for handling cultures to keep them pure. But you won’t need a sterile facility or a spotless house.
Personal Observation:
Most mushroom growth instructions suggest a low light or dark room for mushroom growth; however, I have personally observed mushrooms growing on grass and under direct daylight.
Bromophenol Blue Plates
The bromophenol blue plates are petri plates which contain potato dextrose agar (PDA), a microbial growth medium. The agar causes the media to gel and the potato dextrose (sugar) provides a nutrient source for the fungal mycelia. The plates also contain some antibiotics to suppress bacteria and a fungicide which inhibits the growth of some, but not all, of the possible contaminant fungi. The bromophenol blue gives the plates a blue to violet color.
The most important component of the plates for visualizing the pathogen is the bromphenol blue, which indicates a change in the pH of the agar. When the agar is a basic pH, it remains blue, but when the agar is exposed to something acidic, it changes to yellow. This enhances the ability to distinguish the white mold (S. sclerotiorum) mycelial colonies (which produce an acid) from other fungi that may be growing on the plates after field sampling.
When the plates are placed in a field, the white mold pathogen spores land on the plates and germinate after about 24 hours.
The mycelium (fungal threads), which originates from the spores, begins to grow on the plates. The mycelium excretes oxalic acid, which lowers the pH of the agar surrounding it. This will cause the blue agar to turn yellow. Only a few other fungi will cause this reaction; however, most are not usually found in Nebraska fields. If they are present, they will produce a type of colony on the potato dextrose agar that can be distinguished from that of the white mold pathogen.
Methods of obtaining a culture are: tissue culture, spore germination, or purchase of culture from a culture collection.
Tissue cultures are the simplest way to obtain a mycelial culture. A tissue culture is essentially a clone of a mushroom. Clone is defined as an identical duplicate of an organism. The basic procedure is to sterilely remove a piece of the mushroom cap or stem, and place it on an agar plate. After a week to ten days, mycelium grows from the tissue and colonizes the agar. Great care should be taken to select a fruiting body of the highest quality, size, color, shape or any highly desired characteristic.
Mushrooms are multi-cell fungi. If a piece of mushroom is places on a semi-solid surface such as agar petri-dish, it may grow and divide to produce similar cells.
Mushrooms, like many other fungi, produce long filaments called hyphae. These filaments form a network called mycelia.
You may purchase mushroom growing kit from:
Question/ Purpose:
What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.
The purpose of this project is to determine the favorable environmental conditions (temperature, light, moisture and air) for mushroom growth. Specific questions for this research are:
How does the amount of temperature affect the rate of mushroom growth?
How does light affect the growth of mushrooms?
Is air flow required for mushroom growth?
How does moisture affect the rate of mushroom growth?
Each of these questions require a separate experiment and can be the subject of a different science project; however, you may choose to work on more than one question and perform more than one experiment.
The rest of this project is focused on the effect of light on mushroom growth. You may use it as a base to design your other experiments and study other variables such as temperature or moisture.
Identify Variables:
When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.
The independent variable is the amount of light.
The dependent variable is the rate of mushroom growth or production.
Controlled variables are temperature, moisture, air, growth media and experiment procedures.
Hypothesis:
Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis.
A mushroom can grow in dark or low light environment; however, light does not stop the growth of mushrooms. My hypothesis is based on my gathered information about mushroom growth and my personal observation of natural growth of wild mushroom in open spaces.
Experiment Design:
Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”
Experiment 1: Grow Mushroom using a kit
In order to find out how light affects the development and growth of a mushroom, we need to grow two groups of mushrooms. One in the dark and the other in the light. All other conditions such as temperature and moisture must remain the same, so we will know that the light has been the only factor that may have caused the difference in growth rate. A mushroom kit is a good place to start. The following experiment is recommended if you can purchase a mushroom kit.
Procedure:
Get four identical mushroom kits (Or get one kit and break it down to four identical pieces)
Place all four kits in a room, next to a window. Cover all four kits with clear plastic to preserve moisture. (Leave some openings for air to flow). Cover two of the kits with aluminum paper or a carton box (in addition to plastic) to keep them dark.
Inspect the kits every day and spray them with water to keep them moist.
Record your observations every day. In your observation include the number of pins or visible mushrooms and the size of the largest mushroom (diameter of the cap).
After 30 days (or whatever time recommended by mushroom manufacturer) remove all mushrooms of each group and weight them separately. Record your observations in a table like this.
| Date | Dark Kit 1 | Dark Kit 2 | Light Kit 1 | Light Kit 2 | ||||
| Pins | Max cap | Pins | Max cap | Pins | Max cap | Pins | Max cap | |
| April 1 | ||||||||
| April 2 | ||||||||
| April 3 | ||||||||
| …….. | ||||||||
| Final Total Weight | ||||||||
Experiment 2: Find Mushroom in the nature
Like all other organisms, mushrooms grow where the conditions are favorable. This fact can be used to identify the conditions favorable for mushroom growth. If you live close to woods or a natural park where mushrooms grow, this can be a fun experiment.
Procedure:
Visit a place where natural wild mushroom grows.
Search for mushroom. Finding and picking mushroom is a hobby for some people; however, wild mushrooms may be poisonous. Do not pick or taste mushrooms that you find.
Whenever you find a mushroom, record the temperature, light condition, soil moisture and the type of substrate.
Record your data in a table and use it for analysis and reporting. Your data table can look like this:
| Sample # | Date / Time | Light condition | Moisture | Temperature | Substrate |
Notes:
If you have any type of light meter, use that to determine the amount of light; otherwise, simply write a number between 0 and 10. Smallest number is 0 for dark, largest number is 10 for full daylight with no shade.
To determine moisture of the soil, you can use a soil moisture sensor available from garden suppliers and hardware stores. You may also estimate the moisture by touching the soil and write a number such as 0 for dry, 2 for very low moisture, 5 for medium moisture, 7 for high moisture and 10 for wet.
Substrate type can be animal droppings, dead tree, live tree, soil, sand,…
Experiment 3: Mushroom Mycelia growth
Introduction:
Gathered information indicates that entire mushroom is composed of compressed mycelia and a culture can be obtained from any part of the mushroom. In the following experiment you grow mushroom mycelia on a semi-solid medium such as agar using a tissue culture.
Material:
Agar or gelatin plates
mushroom
toothpicks
cotton swab (such as q-tips)
vegetables (such as carrots, green pepper, squash, potato, etc.)
blue cheese
marking pens
Procedure:
-
- Prepare four agar or gelatin plates. Commercial agar plates such as Sabaroud Dextrose agar plates can be used for fungi growth experiments. Homemade gelatin medium will also work as well.
- Label the bottom of two plates “dark” and two other plates “light”
- Wash a mushroom and dry it. Pull it a part to break it and reveal inside of the mushroom fruit. Use a sterile sharp object to remove a small piece of mushroom and place it on each plate.
- keep the plates at room temperature. next to a window. Cover two of the plates with a carton box to keep them in the dark
- observe the plates every day for 7 days and record the growth of mycelia in each plate. (How many millimeters around the mushroom piece)
Prepare homemade gelatin plates as follows:
pour into sterile disposable petri dishes or muffin cup liners and store in plastic sandwich bags.
For homemade medium you will need:
Plain gelatin
water
sugar
beef bouillon granules
foil muffin cups
muffin pans
measuring spoons
In a saucepan, mix 4 envelops of plain gelatin with 4 cups cold water, 8 tsp. sugar and 4 tsp. bouillon granules (or 4 bouillon cubes).
Bring slowly to a boil, stirring constantly.
Cool slightly and fill either sterile disposable petri dishes or foil muffin cup liners in muffin pans for support, about 1/3 full with the hot gelatin solution.
Cool until the gelatin is solid. Remove foil muffin cup liners from muffin pan and store in plastic zip-lock bags in the refrigerator. Do not touch the surface of the gelatin. Makes 25-30 cups.
Important:
-
- A nutrient agar or gelatin plate that you use in this experiment is good for the growth of many different organisms including bacteria. It is very important to use a sterile tool to transfer a piece of mushroom to prevent cross contamination and growth of other bacteria.
- If you use a knife to cut the mushroom, the knife blade transfers surface bacteria to the inside flesh of mushroom. That is why you pull it apart and break it to access the inner flesh.
- The size of the mushroom sample that you use, can be as small as a dot.
- To sterile a sharp tool, keep it on the flame for a few seconds or insert it in methyl alcohol for a few seconds.
Materials and Equipment:
List of material can be extracted from the experiment section.
Results of Experiment (Observation):
Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.
Calculations:
No calculation is required for this project.
Summary of Results:
Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.
It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.
Conclusion:
Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.
Related Questions & Answers:
What you have learned may allow you to answer other questions. Many questions are related. Several new questions may have occurred to you while doing experiments. You may now be able to understand or verify things that you discovered when gathering information for the project. Questions lead to more questions, which lead to additional hypothesis that need to be tested.
Possible Errors:
If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.
If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.
References:
List of References:
Major Edible Mushroom Species
Myko Web
Mushroom Kits for home growing
I grow Mushrooms
Small Scale Mushroom Production
Mushroom Production Figures
Irish Mushroom Production
The Future of Mushroom Production in the United States
International Society for Mushroom Science
Mushroom cultivation and Marketing in rural areas of USA
http://www.nomi-and-tim.org/mushrooms/
hypha: (pl. hyphae; adj. hyphal)
single, tubular filament of a fungal thallus or mycelium; the basic structural unit of a fungus
(a single Basidiomycete fungal hypha with a septum and clamp connection)
mycelium: (pl. mycelia, adj. mycelial)
mass of hyphae constituting the body (thallus) of a fungus
(mycelium and sclerotia of Sclerotium rolfsii)
