Small Scale Mushroom Cultivation 2

In developing countries mushroom cultivation is gaining more attention as a possibility to use agricultural wastes, and to help alleviate poverty and food insecurity.
Certain mushroom species are rather easy to grow while others demand more specific cultivation methods and temperature. In general, the life cycle of a crop is rather short (varying from some weeks to a few months). Once the cropping cycle is completed the spent mushroom substrate/compost (SMS) can be used as a soil conditioner, or in some cases as animal feed.

Agrodok 40 describes the simplest procedure; i.e. mushroom cultivation on substrates that only need heat treatment.
Certain mushroom species however, like the Rice Straw Mushroom (Volvariella spp.) and the Button Mushroom (Agaricus spp.) can only be cultivated on fermented substrate or compost.
Cultivation of Rice Straw Mushroom is prevailing in the warmer climates of the tropical regions, whereas growing Button Mushrooms predominantly takes place in more moderate temperature climates.
However, the process of composting for mushroom cultivation is a more complex process than the preparation of temperature-treated substrates. Therefore, this second Agrodok on mushroom cultivation (Agrodok 41) covers the lack of information on this specific subject by describing the complete process of composting of agricultural wastes as well as the specific cultivation methods of each of the appropriate species mentioned above.
In a special chapter the process of obtaining good quality spawn and spawn production (propagation material) is treated in detail.  Furthermore, special emphasis has been put on the minimum requirements for growing conditions, mushroom houses and equipment.

Additionally, attention has been given to harvesting and post harvest handling. Since there is a high demand for processed (mostly canned) mushrooms in suburban and urbanized regions, the basics of mushroom processing have been covered in a separate chapter. Finally it seems appropriate to add a chapter on marketing in which the importance and possibilities of the local and regional market(s) are pointed out.
Christaens Group, CNC, Gicom, Hoving Holland, Lensen Vul- en Sluittechniek, Mycelia and Scelta have all supported this Agrodok 41.

Agromisa was established in 1934, and is linked to Wageningen University and Research Centre. Its aim is to exchange knowledge information on small-scale sustainable agriculture and related topics. The target group is the underprivileged population in rural areas. Agromisa's main objective is to strengthen the self-reliance of the target group and to improve their livelihood by sharing experience and knowledge.

Learn How To Grow Mushrooms

Many gardeners wonder if it is possible to grow mushrooms at home. These curious, but tasty, fungi are typically grown indoors rather than in the garden, but beyond this, it is certainly possible to grow mushrooms at home. You can purchase mushroom growing kits, but it is also possible to set up your own area for growing mushrooms. Let’s learn a little about how to grow mushrooms.

Choosing a Mushroom to Grow

Mushroom growing at home starts with choosing the kind of mushroom you will be growing. Some popular choices when growing mushrooms at home are:

shiitake mushrooms (Lentinula edodes)
oyster mushrooms (Pleurotus ostreatus)
white button mushrooms (Agricus bisporus)
You will need to buy spore or spawn of your chosen mushroom from a reputable dealer (many can be found online). For the purposes of mushroom growing at home, you can think of spores as seeds and spawn as seedlings. Spawn is easier to handle and grow mushrooms at home.


Different mushrooms have different growing mediums. Shitake mushrooms are normally grown on hardwoods or hardwood sawdust, oyster mushrooms on straw and white button mushrooms on composted manure.

How to Grow Edible Mushrooms at Home

After you have chosen which mushroom you will be growing and have gotten their preferred growing medium, the basic steps for growing mushrooms is the same. Mushroom growing at home requires a cool, dark, damp place. Typically, this will be in a basement, but an unused cabinet or closet will also work. Anywhere you can create near darkness and control temperature and humidity.

Place the growing medium in a pan and raise the temperature of the area to about 70 F. (a heating pad works well for this). Place the spawn on the growing medium. In about 3 weeks, the spawn will have “rooted”, meaning the filaments will have spread into the growing medium.

Once this occurs, drop the temperature to between 55 F. and 60 F. This is the best temperature for growing mushrooms. Then, cover the spawn with an inch or so of potting soil. Cover the soil and pan with a damp cloth and spray the cloth with water as it dries. Also, spritz the soil with water when it is dry to the touch.

In 3-4 weeks, you should see small mushrooms appear. Mushrooms will be ready for harvesting when their cap has fully opened and has separated from the stem.

Now that you know how to grow mushrooms at home, you can try this fun and worthwhile project for yourself. Many mushroom growers agree that mushroom growing at home produces a better flavored mushroom than what you will ever find at the store.

Mushroom Farming Means Opportunity and Better Nutrition in Tanzania

Delphina Peter Mamiro is mad about mushrooms.

This senior lecturer at Tanzania’s Sokoine University of Agriculture is convinced that local farmers can learn to profitably produce oyster mushrooms in order to improve their household nutrition and generate income for their families. One of 390 African women scientists to win a fellowship from African Women in Agricultural Research and Development, a program supported by Feed the Future and the Bill & Melinda Gates Foundation, Dr. Mamiro is helping advance food security in Tanzania by focusing her research and field work on a nutritious and high-value crop traditionally harvested by women.

“Mushrooms have no cholesterol and are full of nutrients and vitamins,” says Mamiro, who holds a PhD in plant pathology from Pennsylvania State University. “In just 28 days, women can have a crop of oyster mushrooms from which they can make a popular relish.”

During the dry season when vegetables are scarce, women and children collect wild edible mushrooms and preserve them for future use.

“Mushroom gathering can be dangerous due to snake attacks and the risk of collecting poisonous varieties by mistake. Growing them at home is the solution to these hazards,” says Mamiro, who is training groups of local women, men and young people in Tanzania to cultivate and dry oyster mushrooms on their own small plots of land. They use agricultural waste, such as banana leaves, as a base for the mushrooms to grow and environmentally friendly recycled plastic bags for containers.

“Tanzania’s tropical climate is perfect for mushroom production and they can be grown all year round, creating employment, health and wealth,” says Mamiro. She reports that production is, well, mushrooming in popularity, albeit slowly.

“Some households now prefer mushrooms because awareness about their nutritional benefits is growing,” she says. Several farmers in her test groups are selling surplus mushrooms and using the profits for school fees and medicine.

One constraint to expanding mushroom production is that good quality spawn (i.e. the vegetative part of a fungus that allows mushrooms to grow) is not widely available in Tanzania, and smallholder farmers need more training in the full spectrum of mushroom cultivation for the industry to gain traction and become sustainable.

“Untrained farmers are under-producing or incurring high costs for unnecessary inputs, such as industrial fertilizer,” explains Mamiro, who hopes to help them solve these problems.

Despite the challenges, Mamiro is encouraged by the farmers’ progress. “I’m happiest when I see a woman with a basket of mushrooms and children in the household out playing because their stomachs are full of food,” she says.

3 Health Benefits Of Mushrooms

Mushrooms are popping up all over, including in your local produce aisle. You don’t have to be a top chef to prize the lush, earthy flavour of exotic mushrooms. But whether you pick smoky morels or the familiar buttons, you’ll get some newly discovered health benefits.

Safeguard Against Cancer

Mushrooms are rich in disease-fighting phytochemicals, and eating them regularly has been linked to a lower risk of breast cancer in studies of Chinese and Korean women. Mushrooms also prevent prostate cancer cells from multiplying in mice—and might do the same in men.

Supply Hard-to-Get Nutrients

One medium Portobello mushroom supplies 21 percent of the recommended daily intake of selenium and one-third your need of copper; it also has as much potassium as a medium-size banana. Other varieties are just as rich in minerals, a recent analysis found. What’s more, mushrooms retain their nutrients when stir-fried, grilled or microwaved.

Help You Cut Calories

When ground beef was swapped out for mushrooms in lasagna, sloppy joes and chili, adults consumed 400 fewer calories per day, according to a Johns Hopkins Bloomberg School of Public Health study. Researchers estimate that if you substitute mushrooms for ground meat in one meal every week, you can lose five pounds in a year. Just don’t sabotage this fringe benefit by preparing mushrooms with loads of butter. Instead, toss them into a nonstick pan that’s been lightly sprayed with oil, then sauté on low heat until they soften.


Read more at http://www.readersdigest.ca/food/diet-nutrition/3-health-benefits-mushrooms

Health benefits of mushrooms

A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source.

Button Mushrooms are popular in India and are easily available at any gourmet store's vegetable aisle. Listed below are the benefits of mushrooms that we never knew.
Mushrooms are a good source of B vitamins which also play an important role in the nervous system.
Mushrooms are also a source of important minerals. Potassium is an important mineral found in mushrooms. It aids in the maintenance of normal fluid and mineral balance, which helps control blood pressure.
They help to strengthen the immune system as well. Mushrooms provide ergothioneine (which is a naturally occurring amino acid) a naturally occurring antioxidant that may help protect the body's cells.

Mushrooms are the only source of vitamin D in the produce aisle and one of the few non-fortified food sources often grouped with vegetables, mushrooms provide many of the nutritional attributes of produce, as well as attributes more commonly found in meat, beans or grains.
Mushrooms are low in calories, fat-free, cholesterol-free and very low in sodium, yet they provide several nutrients that are typically found in animal foods or grains.

Cultivating King Oyster Mushrooms

Cultivation of the King Oyster Mushroom has expanded rapidly in South East Asia over the past decade. From 1993, growing numbers of companies in China, Taiwan and Japan have begun commercially producing this tasty oyster mushroom. The King Oyster Mushroom is sold fresh on local markets and exported dried or in jars. This mushroom can be found in dried form in Chinese specialty stores. This article reports on ten years of research into this variety in Taiwan and China, and the cultivation techniques.

The King Oyster Mushroom fully justifies its name: it is by far the most flavoursome of the oyster mushrooms. The thick, firm stems have a pleasant texture and a slightly sweet taste. Another plus point is its long storage life compared to other oyster mushroom varieties. This variety can easily be transported over long distances. It has also recently become known that this variety, just like the shii-take, lowers cholesterol levels. An excellent selling point in cultures where cardio-vascular diseases are major killers.
The refined flavour has lead to a considerable price difference with the fungi usually cultivated in the Far East, the shii-take. The price of Pleurotus eryngii is about double that of shii-take in China; little surprise that cultivation is becoming more widespread.

Rare in nature
The King Oyster Mushroom's official name is Pleurotus eryngii:. The name eryngii indicates where the mushroom can be found in the wild: on the roots of umbelliferous plants, particularly Eryngium and Heracleum. It grows as a parasite on these plants - a big difference with the winter oyster mushroom, for example, which grows well on dead hardwood. This variety is extremely rare but it has been identified growing wild in various parts of the world- in North Africa, Central Asia and in the southern regions of the former USSR.

Low yields on straw
The usual methods of cultivating oyster mushrooms on straw give a low yield with King Oyster Mushrooms: from 8 to 12% of the substrate weight. In addition, infections repeatedly occur on pasteurised substrate. The reason is that King Oyster Mushrooms have a different metabolism to other oyster mushrooms. They are less able to decompose lignin so give a higher yield with more easily decomposable forms. But mixing this with pasteurised substrate increases the risk of competitor moulds. This variety is a far slower grower than the winter oyster mushroom or the pink oyster mushroom. This also increases the risk of infection, as it takes longer to fully colonise the substrate. Hygienic working practice is even more essential with this variety.

Growing on sterile substrate
Wood-loving strains that are difficult to cultivate on pasteurised substrate can be grown well on sterilised substrate. This applies to both the Velvet Foot or Enokitake and the King Oyster Mushroom. The substrate should be placed in a container resistant to high temperatures; the mycelium must have enough space to breathe at a later stage. The most commonly used containers are plastic bags (in China) and bottles (in Taiwan and Japan).
Depending on labour costs, the process is more or less automated. Special machinery is available which mixes the substrate, adds water, fills the bottles, makes a hole in the substrate and inserts a plug that allows air though. A 1100 millilitre bottle usually contains about 650 grams of substrate. The bottles are sterilised in man-high autoclaves. A special machine then automatically inoculates the bottles with spawn. The stacked crates then spend about 6 weeks in an incubation room.

Scratching
The next phase can be compared to ruffling casing soil in white cap mushroom cultivation. The mycelium at the top of the bottle is not all the same age; older spawn can cause abnormalities, so a machine 'scratches' away a small part of the upper substrate layer after incubation.
Research carried out in 2002 at the famous Pudong Mushroom Institute in Shanghai confirmed the importance of scratching. Although this treatment slightly reduces the number of fruit bodies (from on average 7.1 to 6.3), the scratched bottles have a better yield and quality.
Harvesting takes place three weeks later.

The cultivation stages
Day 1. Mix sawdust with 40 % (volume) rice bran, moisten, fill in bottles with lid, sterilise within 6 hours, allow to cool to maximum 30 degrees Celsius.

Day 2.   Inoculate with spawn in sterile area.

Day 3 – 40.  Incubate at a temperature of 18.5 – 20.5 degrees Celsius.

Day 41.  Scratch.

Day 42 – 52.  Primordia formation, 8 hours per day 250 lux, RH: 85-95 %.

Day 61 – 65. Harvest, grading, packing, cooling and distribution to auction or wholesaler.

Number of perforations per bag
The number of holes or perforations in the container growing King Oyster Mushrooms has a big influence on the yield. An experiment by dr. Peng, TARI* in 1996 showed that with plastic bags containing 1.2 kilos of substrate, closed by a plug, too few holes gave a lower yield. Bags where only the plug was removed, gave an average yield of 8.4%. Bags slit open at the bottom, then laid horizontally, gave an average yield of 12.8%.

New strains
Around 15 years ago I exchanged a large number of strains between China, Taiwan and a Belgian spawn producer. These strains included a Pleurotus eryngii strain, used in Taiwan for classic selection to develop commercially interesting strains. Unlike common mushrooms, the King Oyster Mushroom  is tetrapolar: this means there are four spores per basidium, that can be used as the base for one spore culture.
A report written by dr. Peng and others in 2001 describes how they combined the required characteristics from two strains (Holland 150 and ATCC 36047). Holland 150, a strain from the former Mycoblanc (taken over in the meantime by Mycelia), gave the highest yield, but a shorter storage life and relatively thin cap. This variety also quickly developed black blotches at high relative humidity. ATCC 36047 had attractive mushrooms with a firm stem and long storage potential.
Peng managed to develop four hybrid strains that reacted differently to changes to the substrate. The optimal substrate composition therefore depends on the strain. One of these strains will shortly be patented.
In China, strain selection is often accomplished by radiating the mycelium. This damages the DNA, which can create mutants. The majority of these mutants have worse traits than the original strain, but the law of averages rules here too. A small number of mutants have excellent production traits and are eventually introduced onto the market as commercial strains.

Optimal substrate composition
Peng and others have done various research studies into the optimal substrate composition. In trials, Holland 150 appeared to give the highest yield with 38 % rice bran, while the yield decreased at 48% rice bran.
Strain ATCC 36047, in contrast, produced more mushrooms as the percentage of rice bran rose.
Other studies aimed at discovering which supplement (in a 50% ratio) gave the highest yield with strain ATCC 36047: rice bran, wheat bran or maize flour. Wheat bran scored highest here for mushroom quality, but maize flour produced the highest yield.
The percentage of supplement is high compared to other exotic fungi, which can be explained by he parasitic nature of this variety. Anyone wanting to attempt cultivating this mushroom, first has to determine the optimal substrate mix for the chosen variety.

Prospects for Europe
In the Netherlands there are only a very small number of King Oyster Mushroom growers. Production of some significance is found in Spain (Micelios Fungisem) and Germany (Pilzfarm Helvesiek), while in the Netherlands Bert Rademakers of Fungi 2000 produces suitable substrate on a small-scale. The superb taste and long storage life give the King Oyster Mushroom a head start. To achieve greater market volumes, the price will have to drop a little. This can only happen if the yields rise and become more stabilised.

* TARI: Taiwan Agricultural Research Institute.

The Indian Mushroom Industry

Introduction - Historical
Mushroom cultivation in India was initiated for the first time at Solan in mid sixties when Dr. E. F. K. Mental from Germany started the work as the FAO consultant at Solan. He started the work on a small scale at the Dept. of Agriculture, H. P. Govt., Solan and successfully grew button mushrooms for the first time in India. Also associated with the project at Solan were the late Dr. P.K. Seth from the Dept. of Agriculture and Dr. S. Kumar. Simultaneously button mushroom cultivation was begun as a pilot project at Srinagar (Kmr) by Mr Stewart (a Britisher settled at Srinagar) along with a team of workers from the Dept. of Agriculture at Lalmandi, Srinagar. At both places the activity grew in size and mushroom growers started growing mushrooms in their houses as a cottage industry. Solan developed more rapidly as the effort at the Dept. of Agriculture (later Himachal Pradesh Agricultural University) was pursued vigorously and the first commercial unit of white button mushrooms in the seventies was put up at Kasauli (near Solan) by Mr. Saigal with the help from the C.O.A., Solan.

Then came, his Highness, the Maharaja of Patiala who started growing mushrooms in the seventies at Dochi and Chail, near Solan on a much larger scale. He monopolised the button mushroom market in India for sometime and mushrooms from his farm would travel, in fresh condition, as far away as Bombay. Meanwhile mushroom growing took the shape of a cottage industry in Kashmir in the seventies where people started growing button mushrooms on a large scale in villages on composts prepared by the long method.

The mushrooms produced in Kashmir were purchased by local canners and marketed in other parts of the country. The growers were producing button mushrooms against greater odds with little know-how available, especially for producing quality mushrooms. The mushroom activity spread to other hilly regions of India like the hills of UP and Tamil Nadu. Growers in the North Western plains started button mushroom growing (as a winter crop) to take advantage of the winter season in this region. Farmers in the NW plains in and around Delhi started growing a winter crop of button mushrooms successfully and marketing the produce in nearby Delhi.

In the mid-seventies Dr. W. A. Hayes was appointed as FAO expert on mushrooms in India and worked at Solan for some time to establish and standardize the facility for the short method of composting at the College of Agriculture, Solan. This resulted in the establishment of an air conditioned cropping house at Solan with a facility for peak heating of mushroom compost. With the contribution of the College of Agriculture at Solan, many students pursued a mushroom programme for obtaining their MS and Ph.D. degrees under the guidance of Prof. R. L. Munjar, Prof. and Head of Dept. of Plant Pathology and Head of Mushroom Research Laboratory, Solan. This was shortly followed by the establishment of a mother composting unit at Solan in the early eighties under UNDP assistance where James Tunney from the UK worked for several years commissioning the mother composting facility at Solan.

The seeded compost at the mother unit was provided to growers in and around the Solan hills to initiate mushroom cultivation. The mushrooms thus produced were purchased by canners and sold in the market. But the consumption of mushrooms was confined to the richer sections of society. The National Research Centre for Mushrooms was set up by the Indian Council of Agricultural Research at Solan in 1983 (June) and I was given the responsibility of starting the Centre at the old/vacated campus of the College of Agriculture, HP Agriculture University, Solan. The Centre took several years to develop the facility at Solan and today we have 15 scientists working at the Centre in 4 different disciplines such as Mushroom Production and Improvement, Mushroom Protection, Mushroom Nutrition and Crop Utilization and Extension.

Today this Centre has attained national and international recognition for the contribution made in mushroom R & D in India and the World. We have most modern laboratories with the latest equipment and instruments for conducting research on various aspects of mushrooms. The biotechnology laboratory for DNA fingerprinting and use of DNA markers in breeding is working full-time on a mushroom breeding programme. The climate-controlled cropping rooms (13) are ready to be commissioned for use in experimentation within a month. The mushroom industry in the eighties increased in size by way of expansion of mushroom growing activities all over the country. Button mushrooms were grown in cooler regions and oyster/straw mushrooms in hotter regions. Meanwhile Pleurotus sajor-caju cultivation became more and more popular all over the country with its minimal requirement of infrastructures. Simple hot water treatment or chemical treatment (Bavistin/formalin) of the substrate was found good enough to protect the substrate from competitor moulds during cropping. In late eighties and early nineties some modern air conditioned mushroom farms were built near cities like Pune, Bombay, Delhi, Chandigarh, Hyderabad and Madras.

With the introduction of spawn of improved/hybrid strains in the nineties by some leading spawn companies from the US and Europe, the industry got a further boost. By the early nineties production of all types of cultivated mushrooms was 5-7 thousand tonnes, and a minor part of it was exported. Besides that, mushrooms harvested from nature like Morels/Kabul Dhingri were exported in greater quantities to Europe and America in the dried form. The mushroom industry saw its biggest expansion in the mid-nineties with production going up to 40,000 tonnes and exports increasing dramatically. About 70-80% of this production was exported to the US and Europe. The exports became more organised in the nineties but the mushroom industry saw a downturn in the late nineties with China causing a fall in international prices by dumping mushrooms produced cheaply in their country, in the more competitive markets.

The prices dropped in the international market from US$ 28-30 to 18-20 and subsequently to 12-14 per case. This could not compensate even for the production costs and the industry in India suffered a set back, and people stopped investing in this area. Today the prices are better around US$ 18-20 per case, with little antidumping duty enforced on Indian exports by the US Govt. The Industry was expected to reach a production figure of 100000 tonnes by the turn of the century, but could reach the half way mark only by 2001. Today, there are limited enquiries on mushroom industry investment when raw materials, labour and technology are available readily at a comparatively lower costs.

We have mushroom growing activity spread over the length and breadth of the country, with local spawn laboratories proliferating in areas of greater demand. The per capita consumption is 15-20g only and by increaszing the per capita consumption to 100g, we should be able to market 100000 tonnes of mushrooms within the country. There are positive signs emanating from the consumer in India, and today cultivated mushrooms are available in all common vegetable shops, grocery stores and departmental stores in small and big towns in India. Mushrooms are more relevant to predominantly vegetarian India.

Mushroom Spawn
Mushroom spawn was initially available from only one centre in India, that was College of Agriculture, Solan and that was the situation until the end of the sixties. Then spawn laboratories were established at Srinagar by Dept. of Agriculture and Regional Research Laboratory with the production of reasonable quantities of pure culture spawn. Some spawn was also produced by Teg's Mushrooms at Chail. The College of Agriculture, Solan became the chief source of supply of spawn in the country. In the eighties some laboratories in agricultural universities started providing pure culture mushroom spawn to the mushroom growers and spawn was also available from the Indian Institute of Horticultural Research, ICAR, Bangalore. With the setting up of the National Research Centre for Mushrooms at Solan, spawn was made available from the Centre to small and marginal farmers and by the late eighties many commercial spawn laboratories were set up in and around Delhi.

About this time Sylvan, USA, started operations in India marketing spawn produced at their European centres. But unfortunately, they did not find the market big enough to set up their own production unit. We do not have large spawn companies operating in India with a R&D back-up facility, the spawn companies that are operating just multiply the spawn and sell it. The availability of strains is limited to S-11, 310, 791, 76 (all non-hybrid strains of A.bisporus) and U-3 (Hybrid). These strains were officially procured in earlier times by different spawn producing centres in the Government sector. A dozen species of Pleurotus are also available in India for cultivation in different agro-climatic zones of India. Also NRCM released 3 new strains of A.bisporus (NCS-100, NCS-101 and NCH-102) in 1997 and 2 strains of A.bitorquis (NCB-6 and NCB-13) in 2000. The cultures of all these strains are available from the culture bank maintained at the centre at NRCM, Solan. Today our centre is the chief source of mushroom cultures in the country. We maintain cultures in our culture bank in a refrigerator (frequent sub-culturing), in liquid paraffin and liquid nitrogen (cryopreservation).

Spawn is prepared and supplied in 500g and 1kg polypropylene packs and one kg of mushroom spawn costs about Rs.50.00 (approx. one US$). Some big spawn companies are supplying spawn to commercial growers in India at almost 3 times the price of that available locally. The quality of the spawn produced by Indian companies is comparable to the best in the world except that it is in small packs of 1kg and the choice of strains is limited. The big companies from US and Europe can make it big in India if they cater to the markets from surrounding areas like China, Indonesia, Thailand and other countries. The biggest advantage India offers is the lower cost of production of spawn with low cost of inputs. Presently Indian market demand is about 8000-10000 tones of spawn. Spawn in India is mostly produced on wheat grain and bajra grain (lesser millet). The spawning rate in button mushroom is 0.5-0.7% and in Pleurotus is about 2% of the wet weight of substrate.

Compost Technology
White button mushroom is still the most commonly cultivated mushroom grown and accepted by the consumer in India. Today we have the most modern compost producing technology in use in the country. There are principally two sets of mushroom growers in India, first those who grow mushrooms seasonally and they produce the compost by a long method in a single phase outdoors in 20-25 days without phase-II, mainly depending upon the selectivity of the substrate for obtaining a single crop of mushrooms. Second is the commercial grower who takes 4-5 crops in a year in environmentally controlled modern cropping houses. These units have facilities for phase-I and phase-II of composting with use of modern machines for turning, filling and emptying. Some of the units have built indoor phase-I bunkers and are using these facilities with good productivity.

Composting by this method is accomplished in 18-20 days (6-7 days in pre-wet, 6-7 days in phase-I, 6-7 days in phase-II). On most of the mushroom farms wheat/paddy straw are used as chief base materials and poultry manure along with N-fertilizer and organic N-sources are used as supplements for composting to bring base materials to desired C:N ratio at the start. Most of the commercial units have excelled in the art of composting with measurement of compost parameters at every stage. A nitrogen percentage of around 2.3% is acceptable after completion of Phase-II as a good measure with moisture content of about 67-68% at spawning, with bulk density of 100-110kg per m2.

As short sized/finely chopped wheat straw is used for composting in India as against 10"-12" long wheat straw used in Europe. This results in our composts becoming denser as a greater quantity fits into a smaller space. The wheat straw is principally available finely chopped, basically prepared as animal feed, as the mushroom industry in India is not so big as yet to attract the attention of the wheat straw handler. Sugarcane bagasse is also used as a base material in some areas for composting in combination with paddy straw, but the composting takes longer by 5-7 days. Farm Yard Manure and Mushroom Spent Compost are commonly used for casing after steam/formalin treatment, as peat is not available in our country. Coir pith after composting is also used in combination with FYM with good results. Casing material is a major bottleneck in button mushroom cultivation in India. Importing Irish peat is expensive for the grower.

Growers
There are two main types of mushroom growers in India, seasonal growers and round the year growers. Both grow white button mushroom for the domestic market and export. The seasonal button mushroom growers are confined to temperate areas such as Himachal Pradesh, Jammu and Kashmir, hilly regions of Uttar Pradesh, hilly regions of Tamil Nadu and North Eastern hilly regions where growers take 2-3 crops of button mushrooms in a year. Also included in the seasonal growers are the growers from North Western plains of India who grow one winter crop of button mushrooms and sell it fresh. The all-season growers are scattered all over the country. The large/export oriented units (EOU) are located in Punjab (near Chandigarh), Dehradun (Near Massoorie hills), Gurgaon (near Delhi), Hyderabad (South India), Madras (South India), Ooty hills (South India), Pune (near Bombay), Paonta Sahib/Nalagarh (HP) and at Goa (Western India). These large units have the growing capacity in the range of 200 to 5000 tonnes per annum. M/s Agro Dutch located in Punjab (near Chandigarh) is the largest EOU with installed capacity of about 5000 tonnes. Some of these units were built with the assistance from foreign machinery sellers/consultants; but entire air handling/cooling machines are now manufactured and commissioned in India.

Waste Recycling
Spent compost has been found to possess good qualities for soil application in place of chemical fertilizers at NRCM, Solan. It was found possible to fertilize the soil with spent compost for the cultivation of soybean/maize with very good results. It can also be used as manure for flower and vegetable cultivation under tropical/temperate climate.

One way of recycling Agaricus spent compost is as its use for casing, after suitable decomposition and water leaching. Many mushroom farms are using decomposed spent compost in combination with FYM or other materials with good results.

Marketing and exports
Marketing of fresh mushrooms is always done in the nearby city, especially Delhi, Bombay, Madras, Chandigarh and others. Most of the produce from big commercial farms is canned in brine and exported to destinations outside India, especially USA. The quality of the mushrooms exported is excellent as most of the big commercial farms are growing hybrid strains of A.bisporus made available to them by multinational spawn companies like Sylvan, Amycel and others. The mushrooms are blanched and preserved in brine in large containers for shipment to distant destinations in containers, and are repacked at the final destination to suit local markets. A quantity is freeze-dried by the producer and exported at a good price. The mushrooms for freeze drying require to be picked as smaller buttons, hence reduced yields.

The retail price of fresh mushrooms in Indian ranges from Rs.50/- to Rs.100/- per kg, depending upon the season. In summer months the prices are higher than in winter months due to the high cost of electricity for cooling. Prices are lower in winter due to arrival of mushrooms into the market from seasonal growers. Prices of mushrooms in the marriage season go as high as Rs.150.00 per kg for a short period due to greater demand.

India being a tropical country, fresh marketing is at a premium, except for a brief winter period. The commonly used packaging is the polythene bag. Most of the mushrooms sold in fresh markets are treated with potassium metabisulphite due to market demand as mushrooms become extra white after the treatment and the casing adhering is also removed.

The export market for India is chiefly the USA, with some quantities going to UAE, Russia, The Netherlands, Germany, UK, Switzerland, Denmark, Israel, Sweden and other countries. There is no quota available from EU for India, and Indian exporters have to sell processed mushrooms in the EU with additional taxes levied as per the laws of the EU, which makes it difficult for the Indian exporters to compete in the EU market.