Oyster mushroom is the 3rd largest cultivated mushroom in the world and it is being cultivated in about 25
countries. n India, it is being produced in the States like Orissa, Karnataka, Maharashtra, A.P., M.P., West
Bengal, Meghalaya, Manipur, Mizoram, Assam, etc. Many species of Pleurotus grow wild on dead decaying
tree logs, stumps, or dead branches of Oyster mushroomliving trees or on dead decaying organic matter mostly during the rainy season. All these species of oyster mushroom are edible except P. olearius and P. nidiformis.There are thirty eight species reported in this genus, out of which only 25 species are commercially cultivated in the world.Different substrates like wheat and paddy straw, saw dust, maize stalks, dried leaves,
waste from food industries and synthetic compost (used for European mushroom) are used for its cultivation. It can also grow on dried logs of soft wood trees and roots of water hyacinth,paper waste and shelled maize cobs.
Different species need different temperature ranges between 20-30°C for their growth. Hence
they are ideally suited for cultivation at different times of the year in various regions. This
mushroom has better prospects in our country, especially as the technology for its cultivation is
simple and cheap. Further, the produce has a longer shelf life, and it can be dried easily.
Artificial cultivation involves the following steps:
i) Preparation of substrate: This mushroom proliferates equally well on both paddy as well
as wheat straw. It should preferably be fresh or not more than a year old using 3-6 cm cut
pieces.
a) Chemical sterilization of substrate: The straw or any other recommended substrate is
steeped in a solution of Bavistin and formalin (Bavistin 75 ppm and Formaldehyde 500 ppm) for
a period of 18 hours. This can be prepared by mixing 7.5 g of Bavistin (50 % WP) and 125 ml of
Formaldehyde (40 %) in 100 litres of water (approximately 10 buckets) in a 200 lit. Capacity
drum or a tub or a tank. This solution is sufficient to steep 20 kg of dry straw in 2 lots of 10 kg
each. Treated straw is put on a sieve for 30 minutes for removal of extra solution. It is then
spawned.
b) Hot water treatment of substrate: The substrate can also be sterilized by boiling in
water (80°C for 40 minutes). If pasteurization facilities are available, bulk pasteurization can be
carried out after over-night wetting at 60-65°C for 2 hours.
ii) Spawning and Spawn run: As soon as the substrate is free from excess of chemical
solution and has cooled down to 25-30°C, it is filled in polythene bags (size 30 x 40 cm) or other
container after mixing the spawn @ 2-3 % by wet weight of substrate (i.e. 200-300 g in 10 kg).
The moisture content of substrate should be 65-70 %. Fresh grain spawn not more than a
month old should be used. The bags should be perforated at 15cm regular intervals for gaseous
exchange with a nail. These are then arranged on raised platform or shelves in a room or shed.
And 20-25°C temperature and 70-85 % RH is maintained for spawn run.
iii) Removal of bags for production of mushrooms: As soon as the substrate is fully
covered with the mycelium, the polythene bags are removed from the substrate. The spawn run
bags are then arranged on a wooden platform or shelves at a distance of 15-20 cm between the
bags. Watering is done twice a day or as required to ensure 70-80 % RH. Walls and floor of the
room are also sprinkled with water. Fresh air is also given once or twice a day during cropping.
Sufficient amount of diffused light is required for normal fruit body formation. Mushroom
pinheads will appear within 7-10 days which can be harvested after 2-3 days. The right stage of
picking is prior to the up curving of the margin of the pileus, before they over-mature. Younger
fruit bodies have longer shelf life. Three to four flushes appear within a period of 4-5 weeks.
iv) Harvesting and Yield: The fruit bodies may arise singly or in clumps and form tiers on
the substrate. They are variable in size, shape and colour. They should be harvested carefully
to avoid any disturbance to other pinheads as much as possible. The debris from the lower
portion of stalk is removed before marketing. These are then packed in perforated polythene
bags for sale in fresh form. Surplus produce can be sun-dried or dehydrated at 50-55°C and
stored in sealed/closed polythene bags for later use or can be pickled in absence of market. Its
yield per unit substrate and area is good which varies from 2.5-3 kg per 10 kg of wet substrate.
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