D.
S MOYO
EMAIL: videmoh@gmail.com
CALLS: +265881013344/+265998994195
SAKUWA MOYO STUDY NOTES
SECONDARY SCHOOL
AGRICULTURE
MUSHROOM PRODUCTION
Mushroom is a small non-green plant with an umbrella shaped cup.
They are non-green plant because they do not have chlorophyll hence they
lack the ability of manufacturing their own food.
Mushroom are not considered as true plants because they are classified
under the kingdom fungi, whereas plants are classified in the kingdom
Plantae.
So in other way mushroom are the fruiting bodies of fungi.
The practice of cultivating mushroom is called fungiculture.
Mushrooms have an underground part called mycelium and the edible part is
normally above the ground.
They obtain nutrient by digesting dead organic matter
Fig. 1 mushroom
PARTS OF THE MUSHROOM AND THEIR FUNCTIONS
PARTS FUCTIONS
Stalk/stem Used to support the cap and also channels water to the
cap
Gills Fertile spore producing parts of the mushroom.
They are allocated under the cap
Ring A membrane located under the cap and circling the
stem.
It is remnants of a membrane that covered the ruptured
gills as the cap grew.
Cap Differently shaped and colored upper part of a
mushroom that protects the gills.
It usually resembles a head-dress hence its name
Volva These are remnants of a membrane that completely
covered the immature mushroom.
It ruptures as the stem grows.
Scales Some mushrooms have rough patches of tissue on the
surface of the cap and even at volva
They are usually remnant of the veil
Veil This is a thin piece of tissue that connects the cap to the
stem in young mushroom.
As the mushroom grows, the veil tears exposing the
gills so eventually spores are released.
In some mushrooms, the ring is left behind on the stem
or the scale is left behind on the cap.
IMPORTANCE OF MUSHROOM PRODUCTION
Mushroom provide us with valuable nutrients such as vitamins, proteins and
minerals
Create employment opportunities that is other may be employed in
mushroom production farms
Source of foreign exchange i.e. when it is done on a large scale it can be
exported to other countries.
Mushroom production helps in clearing up the environment
Assist in crop diversification
Source of medicine into biomediation of oil spills eg medicine for illness
such as tumours
Mushroom are used to flavour meat or soup or mixed into salads.
Mushroom is used for industrial purposes for instance in the manufacture of
colouring and absorbents.
Mushroom are ideal for diabetes due to their low cholesterol content, little
sugar and no starch.
VARIETIES OF MUSHROOM THAT ARE GROWN IN MALAWI
Two varieties are grown in Malawi
i. Oyster
ii. Button
Note that Oyster does not require mush observation as compared to Button
OYSTER VARIETIES (pleurotus Ostreatus)
Fig.2 Oyster
i. Pluerotus spps
It is relatively easy to grow
The yield does not change depending on the substrate being used
The recommended temperature to grow the oyster mushroom is between
150– 300c.
They can be grown in ligrocellulotic land (forestry wastes.)
Most of the substrate requires pasteurization in order to get economic yields
EXAMPLES OF PLEUROTUS SPPS
a. Pleurotus sajar caja
Highly adaptive and prefer temperature of between 220 to 240c.
b. Pleurotus stratus
Produce very well in temperature between 120 to 260c
BUTTON MUSHROOM
There are two varieties that are recommended to be grown
(i). TNS 1
This requires a cropping temperature of 160 to 260c
It has the potential yield of 15kg per m2
(ii). TNS 2
This requires the cropping temperature of 180 to 220
They are also called white button mushroom ( Agaricus bisporus) because
they have white and scaly in colour.
This type of mushroom is also known as Champignon.
These mushrooms are hardy and produce plenty of “fruits bodies”
They are great addition of salads, soups and everyday meals, and they are common
in supermarkets all over the world.
Other varieties of mushroom grown in the world are as follows:
SHIITAKE, OAK MUSHROOM (Lentinula edodes)
This is largely produced in Japan, China and South Korea.
It has a deep, smoky flavor and their firm texture makes them a good
Substitutes for meat.
It is famous for both its great taste and medicinal properties
PADDY STRAW MUSHROOM (Volvariella volvacea)
Volvariella mushrooms can be grown easily if you have access to rice straw of
dried banana leaves.
It is very popular mushroom in Chinese cusine
CHICKEN OF THE WOODS (Laetiporus sulpureus)
Younger specimens of this species are known to taste similar to chicken.
It is also known to be parasitic
ENOIKITAKE (Flammulina velutipes)
This type of mushroom is easy to cultivate and often used in soups.
BLACK TRUMPET (Craterellus cornucopioides)
This is the best tasting edible mushroom in the world
MAITAKE (Grifola frondosa)
This species of mushroom is edible and also known to have anti-tumor
properties and it looks like brain.
TREE EAR FUNGUS (Auricularia Polytricha)
This species is known as jelly fungi which are commonly used in Chinese
Cuisine.
MORELS (Morchella angusticeps)
These elusive, delicious are very popular with mushroom hunters.
It is quite an edible variety.
FACTORS TO CONSIDER WHEN SELECTING SPECIES FOR
MUSHROOM PRODUCTION
1. Availability if waste materials (substrates) used as growth medium
2. Presence of suitable environmental conditions
3. Availability of expertise in growing mushrooms.
4. Availability of capital
5. Market demand for the species of mushroom you want to grow. Always
check the tastes and preferences of consumers in your area. You should aim
at satisfying the need of the consumers.
HUSBANDRY PRACTICES FOR MUSHROOM PRODUCTION
a) Site for mushroom production
The site for mushroom production must be the following qualities:
1. Availability of waste materials to be used as a growth medium in the area, as
a result of farm waste.
2. Climatic conditions; a warm, rainy and humid environment is deal.
3. Nearness to dense forest, this provide ideal conditions for mushroom
growth because of humidity and availability of wood
4. The area must be pest and disease free.
5. Nearness to the market to enable the produce to get the consumers when
they are fresh because mushroom are highly perishable.
6. Readily available clean water for watering to avoid contamination
7. Availability of transport form both produce and substrate materials so that
they reach their area of feed faster
8. Availability of growing mushroom resources.
CONSTRUCTION OF INCUBATION AND PRODUCTION SHEDS FOR
MUSHROOM PRODUCTION
Mushrooms are normally grown in specially constructed sheds.
Before mass growing they are incubated first in the incubated room for
substrate colonization.
The following are the factors to consider when planning sheds for mushroom
production:
1. Construction cost
2. Machinery space requirement
3. Tray or bed size
4. Stacking design
Building for mushroom do not require windows. They should be rodent-
proof with cement floors that have adequate drainage for ease of cleaning
and hygiene.
5. The roof should have sufficient slope to prevent condensed moisture
from dripping into the bed
6. Use insulation materials, to prevent temperature fluctuation and
increase the efficiency of air conditioning.
7. Ensure good ventilation to supply constant flow of fresh air and
prevent buildup of Carbondioxide.
The requirement for successful mushroom growth are controlled
environment with appropriate light, humidity ventilation air pressure PH and
nutrients.
The growing shed can be made out of locally available materials and must
meet the required conditions to favour successful mushroom growing.
The growing house should include a preparation room, dark room
(incubates) and finally the production room to allow the farmer to have a
continuous supply of the crop.
Use of wood should be minimized to prevent the rotting of wood and also to
discourage growth of other fungi.
b) Substrate for mushroom production
A substrate is any substance onto which mushrooms is grown.
This can be made from the following;
1. Finely chopped dry maize stalks or the straws of rice or banana leaves
with supplementation.
2. Shredded maize cobs with or without supplementation.
3. Sawdust with supplementation
The most used supplement are; rice or wheat bran (15%-20%), calcium
carbonate (1%-2%) and water hyacinth (10%-20%)
PROCESSES INVOLVED DURING SUBSTRATE PREPARATION
1. Shredding: substrates such as straws are cut into small pieces. When using
saw dust it is important to compost it first because it contains some
poisonous substances. To increase nutrient status of the substrate lime and
urea are added.
2. Soaking: the substrate is soaked for about 12 hours. However some
substrates do not need any soaking.
3. Brending: after soaking, the substrate is left to loose water for 1 hour. The
moisture content of the substrate can be checked by squeezing. After
draining the water, the substrate is mixed with 20% bran and 2% lime as a
PH buffer.
4. Bagging: polythene bags are used in bagging the substrate.
5. Sterilisation by steaming: for sterilisation, a metallic drum is used. A
wooden racks which is about 21 cm is placed at the bottom of the drum. A
bout 40 litres of water is put in the drum. The bags containing the substrate
are then arranged in the drum at the top of the platform. The bags are
arranged in such a way that they can allow steam movement. The bags are
steamed for 4-4.5 hours.
After sterilisation the heat is turned off and the drum allowed to cool down
for sometimes before it is opened. The substrate is allowed to cool. It should
be then left in a clean environment for 24 hours.
After the substrate is prepared, it should be treated first before spawning
(seedling).
METHODS USED TO TREAT SUBSTRATE IN THE MUSHROOM
PRODUCTION
1. Steam pasteurisation
Pasteurisation is the heat treatment of perishable food to destroy heat
sensitive vegetative cells followed by immediate cooling to limit growth of
the surviving cells and germination of spores.
In this method, pre-melted straw is packed in wooden trays or boxes and
then kept in a pasteurisation room at 600c to 80 0c for few hours.
The temperature of pasteurisation room is controlled by the help of steam
through a boiler.
After cooling the substrate to the room temperature, it is seeded with spawn.
The entire process take 3-5 days.
2. Immersion in hot water
The substrate after chopping (5-10cm) is soaked in hot water (650c -700c) for
one hour.
After draining excess water, spawn is added.
The leached water contains a lot of soluble sugar and phenolic compounds.
Hot water treatment makes hard substrates, to be soft hence the growth of
mycelia takes place very easily.
However, mushroom is not suitable for large scale mushroom production.
3. Chemical sterilisation technique: this is done to kill competitor moulds or
to suppress them.
4. Sterile technique
The chopped substrate after soaking in cold water is put in heat resistant
polypropylene bags and sterilized in an auto-clave for 1-2 hours followed by
spawning under septic condition.
MUSHROOM SPAWNING/SEEDING
This is the process of germinating mushrooms from the spores.
The spores germinate in the mycelium
In nature, spores germinate and grow very poorly, therefore a better method
of seeding the mushroom substrate is required.
The mushroom mycelium is propagated on the base of the stem-sterilised
cereal grain.
This cereal grain mycelium mixture is called spawn. Most of spawn is made
with mycelium from a stored culture rather than mycelium whose parent was
a spore.
This is because each spore is likely to yield a new strain and its performance
would therefore be unpredictable.
Preparing spawn is highly is highly technical task that is not practical for
most mushroom growers to perform. Therefore it is mostly produced by
specialised companies that supply to growers with pure culture spawn.
An alternative method of seeding mushrooms at home requires the following:
Requirement:
1. Growing trays of 60cm by 90cm and 17cm deep
2. Compost manure
3. Mushroom spawn
4. Peat moss
5. A piece of wood or flat object
6. A water mister
7. Some old newspaper
Procedure
1. Place the well-rotten compost into the growing tray and water
2. Take 1-2 cups of day button mushroom spawn flakes and mix it into the
compost
3. Press the mixture by use of peace of wood into the tray and set it overnight.
4. Keep the temperature between 650f and 700f for 2-3 weeks, misting daily
with a spray bottle.
5. When the white webbing in the surface of the soil are seen, apply 1.5-5cm
layers of moist peat moss and cover with a layer of newspapers. The
newspaper must kept moist.
6. Spray the newspaper twice daily and maintain a temperature of 550f.
7. After 10 days, remove the newspaper and continue to mist twice daily.
Eventually tiny white pin heads will start sprouting. Once the button
mushrooms reach the desired size, they are picked and news mushrooms will
grow in 10-14 days for up to 6 months.
c) Management of mushroom fruiting
Mushrooms must be grown under controlled environmental conditions.
These conditions must be at optimum for high production. Hygienic
practices must be observed to control pests and disease throughout the
growing cycle.
Some of the pests which attack mushrooms include:
1. Mushroom Flies
2. Phorid and scarid flies
3. Rats
4. Termite and mites
5. Beetles
6. Rodent
Some of the disease that affect mushrooms are:
1. Bacterial diseases such as blotch
2. Fungul diseases such as trichodema and verticillium/dry bubble, mat
Sanitation and strict hygiene are the most important preventive methods for
pest and disease control.
The main aim is to exclusion and elimination of pathogens or pest.
However, flies can also be controlled through spraying or use of biological
control method.
OTHER PRACTICES OF PREVENTING PESTS AND DISEASES
1. Always keep door closed and avoid any practices that expose substrate
pathogens or pests during spawning.
2. Keep mushroom flies from entering mushroom houses by installing
screens on windows and doors.
3. Inspect mushroom bags or beds carefully for easy detection of pests and
disease. Keep mushroom bags or bed clean by removing any mushroom
debris or stumps shortly after harvest.
4. Always keep the floors clean
5. Do not dump ant waste that attract mushroom flies near mushroom
houses
6. Disinfect mushroom houses thoroughly before fresh seeding
7. Clean and disinfect equipment used for growing mushrooms frequently.
8. Wear clean clothes and shoes and wash hands before entering a
mushroom house.
d) Mushroom harvesting
The right stage for picking is judged by shape and size of the fruiting body.
In young mushrooms, the edge of the cap is thick and the cap margin is
enrolled.
For matured mushrooms, the cup becomes flat and inward curling starts.
It commences at the first sign of the buttons, often on a 7-10 day cycle and
may last for up to 2 months.
Matured mushrooms are harvested by grasping the mushrooms by the base
and performing a twisting counter clockwise motion by hand.
Avoid pulling the mushroom straight out of the mycelium with too mush
force as this can damage mycelium.
After harvesting, use a small brush to gently brush off any vermiculate or
substrate left on the mushrooms.
The stems are trimmed and the mushrooms are usually graded straight into
boxes for transportation and sale.
Mushroom deterioration can be reduced by cooling.
Mushroom are highly perishable and should be marketed as soon as
possible after harvesting.
Mushroom can be picked at the button, cup or flat stage depending on the
market requirements.
Buttons are small unopened mushrooms.
Cups are older buttons where cup has begun to open.
Flats cups that have fully expanded to expose all gills.
Marketing cost for mushroom includes; packaging, transport, commissions
and taxes.
Reference
Kalande, w. (2018). Excel and succeed, Senior Secondary Agriculture Students
book 3. Nairobi; Kenya. Longhorn publishers limited.
