Analysis shows that 53 nitrogen compounds are found in a single strain of Agaricus bisporus. Volvariella volvacea contains 206.27 mg of vitamin C per 100 mg of fresh fruiting body. Mushrooms contain thiamin; riboflavin, niacin, biotin and ascorbic acid, all essential for human health. The most common fats are also available in different mushrooms. The carbohydrate content varies from three to 28 per cent. The mineral content is superior to that of meat and fish and nearly twice as that of the most commonly used vegetables.

Medicinal value: Mixture of mushrooms has been used for healing purposes for thousands of years. The carbohydrate rate in mushrooms is very low, therefore these are mainly recommended to diabetic and anemic patients, owing to their high folic acid content. Some mushrooms have antibiotic properties, while some others are anti-allergic.

Other uses: Some mushrooms are mycorrhizal, used to improve soil fertility, for reclamation and for introduction of exotic plant species, others are used as bio-control agent.

Edible mushrooms: There are thousands of varieties of mushrooms throughout the world, out of them 2,500 species are identified as edible and only 20 of them are popular. The white button mushrooms or crimini or portabella or portobello mushrooms (Agaricus bisporus), have commercial value. The people of Sindh, mostly of the desert and mountain (Thar and Kohistan) areas are familiar with the local desert mushroom, commonly known as Khumbhi. The people of the hilly areas of Kashmir, NWFP and Punjab are familiar with black morels. White umbrella type mushroom locally known as Khamiri is also eaten by people of Balochistan, Sindh and Punjab.

Cultivation: The mushrooms are independent of sun light. The mushrooms absorb oxygen and exhales carbon dioxide. Different artificially cultivated mushrooms need different range of temperature, humidity, light and ventilation. In fact, the mushrooms are one of the most difficult commodities to grow. Intensive labour is required to produce a consistent, high quality crop.

Model mushroom house: The mushrooms can be grown year after year with full commercial excess, if proper growing conditions are provided and adequate facilities are available. Such conditions can be fulfilled in shelf growing, by construction of properly insulated and ventilated mushroom houses. Or otherwise, when nature favours, it can be cultivated in green houses and other suitable places.

Model mushroom house: A model mushroom house must have store room, pasteurisation room, spawn preparation and spawning rooms, spawn running room, cropping room as well as packing and preservation room.

Basic requirement for growth: The heating and cooling system can regulate the temperature as per requirement. Most types of mushrooms grow well within range of 80-95 per cent humidity that could be arranged with the help of desert room cooler and or sprinkling water near mushroom beds.

Most mushrooms do not need regular light and grow well at normal natural light. Indirect sunlight/ fluorescent lighting five to 10 feet away are adequate. But, regular light is necessary in case of oyster mushroom.

Mushroom culture and spawn: The propagating material used for mushroom cultivation is called spawn. It is equivalent to the seedlings developed from seeds of higher plants as in case of vegetables. Actually, the spores (serve as a mean of seed) of the mushrooms are so small and could not be seen with necked eye; therefore, mushroom grower cannot handle them. Technical laboratory person could inoculate sterile cereal grains with the spores or pure mycelial culture of the mushroom and incubate that until a viable product is developed.

Growth medium: Different agricultural and industrial straw wastes can be used for cultivation of mushrooms. Mostly, wheat, paddy, barley, oat and gram straw, banana, sugarcane and maize leaves etc. can be used as substrate (medium) for cultivation.

Harvesting of mushrooms: The mushrooms are harvested by hand picking for six to ten weeks. In case of oyster mushroom, harvesting could be done with the help of sharp knife or blade, at the base of the stipe (stem or stalk), but the stalk should never be cut on the bed. If there are many pinheads around the mushrooms, cut that mushroom very carefully, so that the near by pins do not be disturbed.

Any solid portion of mushroom left in the bed should be removed otherwise it would harbour flies and other insects. Any mature mushroom and any harvested or diseased, should also be removed at each harvesting. All stalks and refuse must be removed from the house and destroyed, to minimise risk of development of diseases and pests. Polyethylene bags, trays or beds should completely empty on the completion of harvesting, and the entire growing area must be pasteurised with steam before a new crop is started.

Yield: The mushrooms yield in cycle and subsequent flushes can be harvested till the conversion of waste in to mushroom or up to contamination or till attack of insect pests or diseases. Approximately, the mushrooms yield equal to 100 per cent of substrate dry weight.

Marketing: Only some types of wild edible mushrooms e.g. black morels, desert mushroom and button mushroom are being collected, gifted, marketed and eaten by rural population. These, as well as other artificially cultivated mushrooms could be marketed in local and foreign markets. The marketing or import and export value of mushrooms could be realised from the reports of the Export Promotion Bureau.

Physiological problems: Premature opening of the pileus (or cap) occurs due to high temperature or high concentration of carbon dioxide of the mushroom growing room (or area). High temperature also favours the development of moulds and bacteria, which soon destroys the spawn or whole crop. If the temperature will be too low, the development of spawn, spawn running and other growth stages will be disturbed due to retardation or arrestation.

The mushrooms are subjected to many insect pests, nematodes, fungal, bacterial and viral diseases; hence a little carelessness in the different steps during mushroom cultivation can play havoc. Some pests and diseases cause damage to the spawn and lead to reduction in yield.

Integrated pest and disease management: All insect pests and diseases can be controlled through adopting the following methods: strict control of physiological or environmental conditions; substrate or compost and casing soil should be free from ammonia and all sources of pests and diseases; disinfecting the substrate or compost, doors, floor, walls, ventilators, all equipment and heating the growing room at 70 degrees C for 12 hours before or after each crop; discarding the contaminated material and using recommended chemicals, after the identification of insect pest or disease; where mushrooms are grown in-door, doorways and other opening should be proofed against entry of insect pests and disease causing organisms.