Cover Image
close this book Bioconversion of Organic Residues for Rural Communities (1979)
close this folder Mushroom production technology for rural development
View the document (introductory text)
View the document Materials and methods for growing mushrooms under natural or field conditions
View the document Growing mushrooms under semicontrolled conditions
View the document Results and discussion
View the document References
View the document Discussion summary

Materials and methods for growing mushrooms under natural or field conditions

Materials and methods for growing mushrooms under natural or field conditions

The Mushroom Bed Foundation The foundation for bedding material can be soil, concrete, or a wooden bench. A soil foundation is made by raising the soil in the same manner used to build a garden plot to a height of about 12 cm above ground level. It is surrounded by a canal 30 cm wide and 15 cm deep. The earth excavated from the canal is used to elevate the foundation The width of the foundation should be 45 cm, and the length 1 m or more. Sandy soil will not make a strong enough foundation, but this can be remedied by cementing the sides or by constructing a wooden bench 30 cm high with the rest of the dimensions the same.

Rice Straw as Bedding Material

Thoroughly dried, long rice straw is preferable. Properly prepared straw produces a better yield of mushrooms compared to the yield when care is not taken to provide a strong base.

The straws are bundled to a size of about 8 cm in diameter, tied at the middle with abaca twine or any good substitute, cut to a uniform length of 45 cm and soaked in water for three hours. The soaked straw bundles are laid crosswise side by side on top of the bed foundation until the whole length of it is covered. All the butt ends are placed on one side in a layer, alternating between layers. If the butt ends of the first layer are on the left side, the butt ends of the second layer must be on the right side. This manner of arrangement is continued until four to six layers are made. About 240 bundles are needed for a six-layer, 4-metre-long bed. Each layer must be pressed firmly to make the surface level, and should be watered.

Simultaneously with the bed preparation, several crumpled newspapers are soaked in a container with 3 9 of urea per gallon of water. This "fertilized" paper is planted along with the mushroom spawn or seed. The mushroom spawn and soaked paper are first distributed on top of the layer in thumb-sized pieces. The plantings are 5 - 8 cm from the edge of the straw and 5 cm apart. For every six-layer bed 4 m long, three bottles (16 fl. oz.) of spawn are used. One-half bottle of spawn is apportioned to plant one layer. The spawn is buried with the paper 4 cm deep in the layer. The same procedure is repeated on the remaining layers. Any left-over straw is mounded on top to a thickness of about 10 cm at the centre.

The straw bed is protected by an elevated, transparent plastic sheet immediately after the planting. The cover is attached to a bamboo frame to prevent the moisture that accumulates on the plastic from spilling onto the straw.

During the dry season, a four-layer bed is recommended because of lower relatively humidity. Beds of six or more layers are possible in the wet season.

Banana Leaves as Bedding Material

Dried banana leaves, still hanging on the plant, are gathered and cut to a uniform length of 45 cm, bundled to a diameter of 8 cm, and soaked in water for three or four hours

The leaf bed is made in a manner much the same as that used for straw; i.e., the bundles are laid side by side crosswise on the bed foundation, watered, pressed, and planted. Four or sixlayer beds are constructed, depending on the season. The leaf bed also requires the elevated plastic sheet on a bamboo frame immediately after planting.

Care of the Bed

For both rice-straw and banana-leaf beds, no water should be given for the first five days after the bed preparation. During the dry season, the bed may be watered gently but generously on the sixth or seventh day after planting, and this should be repeated once a day until the mushroom pin-heads have developed. During the rainy season, the bed may not need further watering, or at least not as much as during the dry months. Water is applied more along the sides of the bed in the rainy season.

When the mushrooms are at the pin-head stage, the bed should not be watered. Water should be applied only when the mushrooms reach the size of corn seeds and the bed has become somewhat dry.

Harvesting

Under normal conditions, the first harvest of mushrooms is taken 10 to 14 days after planting. The harvest usually lasts for three consecutive days. This is the so-called first flush. The average daily production is 1.2 kg. The bed rests for five to seven days, and another crop is harvested over another two- to three-day period. The average production for the second harvest is 0.42 kg. This manner of production may continue for a month or even longer.

During harvest, the mushrooms must be carefully pulled out whole from the bed. Any portion left behind will decay and permit bacterial soft-rot to spread in the succeeding crops, causing a drastic reduction in yield.

Yield

For a standard 4-metre, six-layer bed, a harvest of 7 kg of buttons or 12.6 kg of fully mature mushrooms can be obtained. This quantity represents the total from the entire productive life of the bed.

Advantages and Disadvantages of These Methods

Both rice-straw and banana-leaf beds are highly adaptable and inexpensive for growing mushrooms as a family project in the rural areas, where labour and materials can be obtained free. Sudden changes in weather conditions do not materially affect production.

Both types of bed require a large quantity of bedding material Yields depend on the volume of bedding material used. Either kind of bed may be hard to manage. Because of side exposure, they easily become infested with pests and diseases.