- Oyster mushroom is scientifically known as Pleurotus ostreatus.
- They are most cultivated edible mushrooms in the world.
- Oyster mushrooms are suited to tropical & temperate conditions.
- Oyster mushroom can be cultivated on Steamed Straws (mostly in Nepal), Saw Dusts, Maize Cobs after removing grains, Rice Bran, Wheat Bran, Wheat Straw, etc.
- Naturally, they are found growing on hardwood trees & conifers too.
- They are rarely found associated to herbaceous plants (Except P. eryngii).
- Oyster mushroom cultivation is done in Early Winter in Nepal condition and spans to a period of two months.
- Marketable production starts from 2nd month.
- A black plastic tunnel house (to avoid sunlight) made of bamboo (being cheap) or a house (cemented/mud cemented) that can be maintained in complete shade.
- Disinfectants like Formaldehyde, Rectified Spirit, Phenyl.
- Rice Straw as substrate cut into small finger size by chaff cutter.
- Mushroom Spawn (Seeds) from NARC, Khumaltar (Recommended).
- Drum (×2) for steaming the cut Rice Straw.
- Drum Size Circular Iron Net tied by two strong sticks.
- Bricks, Jute Strings, A pencil size pointed twig, Black Plastic Film.
- Mushroom plastic bags of size12”×26” or 16”×26”.
- Wooden Stove or Kerosene Stove for heating.
- Buckets, Mugs, Broom, Plastic Sacs as required.
Step 1: Disinfection of Shade House
- Clean the house or place with broom where mushroom is to be cultivated.
- It is most important step on which production is dependent.
- For temporary tunnel houses uproot grasses & other weeds & use agricultural lime by broadcasting them on ground.
- For cemented houses, clean the floor & walls with 10% formaldehyde solution/ 10% Phenyl solution.
- Make sure the room is free from insects.
- After cleaning, leave 4 mugs of formaldehyde solution on each corner for fumigation up to 3-4 days.
Step 2: Collection & Cutting of Straw
- The Rice Straw; preferably straight ones is collected.
- The straight ones can be easily transported & cut.
- They are now cut by a chaff cutter or by a local khukhuri as available.
- Small finger size pieces are preferred.
- Chaff Cutter gives uniform pieces; hence it should be used as far as possible.
Step 3: Steaming the Rice Straw
- Soak the cut rice straw for a minimum of 5 hours in a drum with water.
- On another drum, stack a pile of 3-4 bricks in a triangular fashion.
- Now, on the triangular base, keep the circular iron net tied to a stick and make it movable from beneath by tying 4 long jute strings on four sides of the net.
- Now, put the setup with stability on the stove.
- Fill the drum with water up to the level of bricks.
- Then, pile the soaked straw directly into the drum or by keeping them in a plastic sack & then into drum.
- Cover the top of the drum tightly via plastic film & heat till ½ hour after steam starts coming.
Step 4: Mushroom Packing
- After steaming, the straw are put on a clean, disinfected & even floor for drying as hot straw can kill our spawn.
- To test whether the steamed straw is well dried or not, we hold them in our fist and pressurize them with fingers. It no water comes out of fist, then it is fully dried and ready for packing.
- Now, disinfect hands with rectified spirit before packing.
- Take a mushroom plastic bag and pile some straw tightly in it up to 10cm giving a cylindrical shape.
- Then, put the mushroom spawn on the edges and make a layer of it.
- Follow the later two steps repeatedly till the bag is full and tie its open very tightly with jute strings. The packing be very compact.
- Now, pierce some holes (up to16; randomly) with pencil size pointed twig.
Step 5 : Stacking of Packed Plastic Bags
- The packed bags must be preferably hanged with plastic strings from a rigid support in tetrad shape by four strings & making a stack of 4-5 floors of plastics bags with a tight string tied in between them.
- We can also use bamboo or iron rods 2 in number and held together above ground with bricks beneath them as supports.
- It is essential to keep them above ground for avoiding contacts with rodents, competitive fungus and ground insects.
Step 5 : After Care & Harvest
- The Oyster Mushroom needs solitary environment for its growth and production. Hence, any bags contaminated are culled out immediately.
- The major symptoms of contamination and infection are greenish demarcation and black patches which are mainly due to competitive moulds like Trichiderma, Verticillium, etc.
- Check out for rodents attack as they tear the packed plastic bags for eating the straw.
- Check out for insects attacks if any, find the cause & eliminate them as well.
- After 3-4 weeks the bags are fully covered with hyphal mass and look whitish in color and sometimes even give rise to basidias.
- After this stage the bags are either fully removed or given long cuts at 4 to 5 places. After 1-2 weeks more, they are marketable.
- At this stage, regular mist irrigation at an interval of 2-3 days is given. After they attain palm size growth, they are detached & packed for selling in market.
Bachelor of Science in Agriculture
Agriculture & Forestry University
Central Campus, Rampur, Chitwan