Mushroom Educational Trunk

MUSHROOM GROWTH AND CULTIVATION: Lesson 2

This study on the importance of mushrooms in nature will provide students the chance to observe mushrooms in action first hand. Students will come away with the knowledge that mushrooms are the premier recyclers on the planet and that mushrooms will decompose almost anything organic. Students will be amazed as they watch mushrooms utilize agricultural waste products such as straw for food and over a period of a few weeks see beautiful mushrooms form on the once useless product.

TEACHER'S MATERIALS

You will need the following:
1) The Mushroom Kit
2) An Overhead acetate of the Mushroom Cycle
3) Any variety of fresh mushrooms (if available)

METHODS Begin by showing your class some of the fresh mushrooms. Allow the students to handle them by passing them around. Explain that mushrooms are the reproductive structures of fungi, and discuss their life cycle by using the overhead and the narrative which are provided.

Explain to your students what the mushroom growing kit is (mushroom spores that have been put on sterilized grain and straw) and what to expect over the next few weeks. (The threadlike white mushroom mycelia will consume the straw and then mushroom fruiting bodies will appear).

You may instruct them to keep a journal, noting the changes that take place as the mushroom mycelia capture the food source (substrate).

Discuss the importance of eating only mushrooms that are known to be edible or that have purchased from supermarkets or restaurants, and explain that some mushrooms in the wild may be poisonous.

Insure your students learned the basics of mushrooms in nature by having them take the multiple choice test that is provided or by other means if desired.

THE MUSHROOM LIFE CYCLE

TEACHER: the following narrative accompanies the enclosed overhead transparency. You may also wish to draw it on the chalkboard or photocopy for handouts. Important terms are highlighted.

NARRATIVE
Mushrooms are the fleshy members of the Kingdom Fungi. Unlike green plants that are grown from seeds, mushrooms originate from spores (1). A spore is so small that it can only be seen under a microscope. Millions of spores grouped together look like dust. Spores are produced in the gills on the underside of the mushroom cap. Once spores are produced they are dropped, and when conditions are right they germinate (2) to form mycelium or hypha . These hypha divide and over time form into hundreds of threads or hyphae or mycelia (3) The hyphae forms the feeding body or mycelium of the mushroom. The feeding body or mycelium often goes unnoticed, as it is usually under the ground or inside a decaying organic object such as a tree. Mushroom mycelium can andwill feed on many agricultural waste products such as straw (the food source or substrate for the mushroom kit). Mycelium will also feed on such things as banana peels, corn cobs, coffee grounds or almost anything organic. As the mycelium begins to consume its food source it begins to take on a whitish appearance. When it has consumed sufficient quantities and climatic conditions are right, (which is usually a drop in temperature and an increase in precipitation) the mycelium is triggered to begin primordia formation (4). The formation of primordia is the beginning of the final stage in the life cycle of the mushroom. Only a few days to a few weeks are required for primordia development (5). Before long a mature mushroom begins to release billions of spores, which will later germinate, guaranteeing that the cycle can continue.

ABOUT THE MUSHROOM GROWING KIT

The mushroom growing kit is composed of a wheat-straw medium that has been selectively inoculated with the oyster mushroom( Pleurotus ostreatus).By following the simple instructions inside the care card the kit will produce mushrooms in approximately 3 to 4 weeks.

The kit will continue to produce for another 1 to 3 months depending upon how well the instructions are followed. The kit will yield somewhere in the range of 1 to 3 pounds of delicious gourmet mushrooms that are perfect in many dishes (recipes included).

When the kit first arrives small areas of white growth are noticeable. This is the mycelium (hyphae) beginning to consume the wheat-straw. Over the next few weeks the mycelium will spread throughout the straw and the entire kit will takeon a whitish appearance. This period of growth parallels that of mushroom myceliumracing through substrate in the summer or warmer months of the year.

After approximately 2 to 3 weeks the kit will have consumed sufficient nutrients to begin primordia formation. By placing the kit inside a refrigeratorfor approximately 5 hours at 45 degrees the mushroom mycelium will by tricked into thinking the fall months have arrived and that it is time to fruit.

Mushrooms will begin to form around the small holes that are spread throughout the surface of the kit. In about 7 to 14 days mushrooms of harvestable size can be seen. The kit will produce successive flushes every 10 to 14 days given the right climatic conditions.

GLOSSARY

Gills-The spore-producing blades on the underside of a mushroom cap.

Hypha-A threadlike fungal cell, the basic structural unit of a mushroom.

Hyphae-The plural form of hypha.

Mycelium-A complex network of hyphae; the vegetative portion of a fungus

Primordia-The mushroom at the earliest stage of growth.

Spores-The reproductive unit of a fungus, usually a single cell.

Mushroom Growth and Cultivation Worksheet
Name:
Class:

Read each question carefully, then write the best choice on the line next to the question.

1. Mushrooms are members of which of the following Kingdoms?
A) Plant
B) Fungi
C) Animal
D) none of the above.

2. Mushrooms originate from:
A) seeds
B) spores
C) both A & B
D) none of the above

3. Mycelium is made up of:
A) hypha
B) hyphae
C) both A & B
D) none of the above

4. Mushroom mycelium can and will feed on:
A) corn Cobs
B) straw
C) almost anything organic
D) all of the above

5. Climatic changes required for primordia formation include:
A) a drop in temperature & an increase in precipitation
B) an increase in temperature & an increase in precipitation
C) a drop in temperature & a decrease in precipitation
D) none of the above

6. Spores are produced in:
A) the stem of a mushroom
B) the gills of a mushroom
C) both A & B
D) none of the above

7. Millions of spores grouped together look like:
A) ink
B) water
C) dust
D) mud

8. Which part of the mushroom often goes unnoticed?
A) gills
B) hypae
C) mycelium
D) both B & C

9. What is the food source inside the mushroom kit?
A) oats
B) straw
C) corn cobs
D) none of the above

10. The whitish growth that can be seen inside the mushroom growing kit can be described as:
A) spores
B) mycelium
C) hyphae
D) both B & C

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