OYSTER MUSHROOM1.INTRODUCTION
Oyster mushroom (Pleurotus sp.) belonging to ClassBasidiomycetes and Family Agaricaceae is popularly known as ‘dhingri’ in India andgrows naturally in the temperate and tropical forests on dead and decayingwooden logs or sometimes on dying trunks of deciduous or coniferous woods. Itmay also grow on decaying organic matter. The fruit bodies of this mushroom aredistinctly shell or spatula shaped with different shades of white, cream, grey,yellow, pink or light brown depending upon the species.
It is one of the most suitablefungal organisms for producing protein rich food from various agro-wastes orforest wastes without composting.
2.OBJECTIVE
The main objective of the exerciseis to present a small scale viable bankable model production unit using moderntechnology.
3.BACKGROUND
3.1Origin
Cultivation of a sp. of oystermushroom (Pleurotus ostreatus) was initiatedon experimental basis in Germany by Flack during the year 1917 on tree stumpsand wood logs. Growing technology wasperfected in USA by Block, Tsao and Hau.
Cultivation of different varietiesof oyster mushroom was initiated in India in the early sixties. Commercial cultivation began inmid-seventies.
3.2Botanical Description
The oyster mushrooms have threedistinct parts- a fleshy shell or spatula shaped cap (pileus) , a short or long lateral or central stalk called stipe and long ridges and furrowsunderneath the pileus called gills orlamellae. The gills stretch from the edge of the cap down to the stalk andbear the spores. The spores are smooth, cylindrical and germinate very easilyon any kind of mycological media within 48-96 hrs. The mycelium of Pleurotus is pure white in colour.
3.3Production
Oyster mushrooms are the thirdlargest cultivated mushroom. China, the world leader in Oyster production,contributes nearly 85% of the total world production of about a million tonnes.The other countries producing oyster mushrooms include Korea, Japan, Italy,Taiwan, Thailand and Phillipines. The present production of this crop in India isonly around 1500 tonnes due to low domestic demand. Another inhibiting factoris that export demand orders are large and can be met only if a linkage isdeveloped between producer, cooperatives and exporters.
3.4Economic Importance
The economic importance of themushroom lies primarily in its use as food for human consumption. It is rich in Vitamin C and B complex and theprotein content varies between 1.6 to 2.5 percent. It has most of the mineralsalts required by the human body. Theniacin content is about ten times higher than any other vegetables.
The folic acid present in oystermushrooms helps to cure anemia. It is suitable for people with hyper-tension,obesity and diabetes due to its low sodium : potassium ratio, starch, fat andcalorific value. Alkaline ash and high fibre content makes them suitable forconsumption for those having hyperacidity and constipation. A polycyclicaromatic compound pleurotin has been isolated from P. griseus which possess antibiotic properties.
The spent straw can be re-cycled forgrowing oyster mushroom after supplementing with wheat or rice bran @ 10-15 %and also for preparing compost of white button mushroom after suitablesupplementation with nitrogen rich horse or chicken manure (sun-dried beforeuse). The spent straw can be used as cattle feed and also for bio-gasproduction, The slurry can be used as manure.
4.MARKET ANALYSIS AND STRATEGY
4.1Demand and Supply Patterns
This mushroom is not as popular aswhite button mushroom in the domestic market. A few units are cultivating itcommercially for export market. Cultivation of this mushroom on commercialbasis would be more profitable as compared to white button mushroom as capitalcosts are low.
The cultivation of this variety of mushroomis very simple and economical in rural areas where raw materials and facilitiesrequired are easily available.
Marketing of fresh oyster mushroom doesnot pose any problem at present due to very low production. However, asproduction increases linkage of producers with domestic markets and exportoriented processing units will need to be developed to ensure remunerativeprices to the producers.
Generally, export orders are too bigto be met by a single grower and as such co-operatives have to be encouraged topool their produce for trading the crop in a dried powder form in internationalmarkets.
4.2Import / Export Trends
About 11,797 tonnes of freshmushrooms and 4,099 tonnes of preserved mushrooms were exported to foreigncountries viz. U.S.A., France, Ireland, U.A.E., Russia etc. during the period2001-2002. The quantity of oyster mushroom exported is much lower than that ofbutton mushrooms which constitute the major share of exports.
4.3Analysis and Future Strategy
Species of Pleurotus are cheapest and easiest to grow among all the cultivatededible mushrooms. Cultivation does not require complicated substratepreparation technique as in case of button mushroom. The former can be grown onnon-fermented, almost fresh plant residues (agri-wastes containing lignin andcellulose). Substrate preparation does not require controlled environmentalconditions as in case of button mushroom.
The crop has got a number ofvarieties varying in shape, colour, texture and aroma which can be cultivatedthroughout the year under varied agro-climatic conditions. Faster growth rate and early cropping isobserved. About 5 to 6 crops can betaken in a year as the total cropping period is 60 days.
5.PRODUCTION TECHNOLOGY
5.1Agro-climatic Requirements
Oyster mushroom can grow at moderatetemperature ranging from 20 to 300 C and humidity 55-70% for aperiod of 6 to 8 months in a year. It can also be cultivated in summer monthsby providing the extra humidity required for its growth. In hilly areas above900m. (m.s.l.), the best growing season is during March/April to September/October and in the lower regionsfrom September/October to March/April.
5.2Growing and Potential Belts
The major states in India producingthis mushroom are Orissa, Karnataka, Maharashtra, Andhra Pradesh, MadhyaPradesh, West Bengal and most of the North Eastern hill states.
5.3Varieties Cultivated
Among all the cultivated mushrooms Pleurotus has maximum number ofcommercially cultivated species suitable for round the year cultivation. Allthe varieties or species of oyster mushroom are edible except P. olearius and P. nidiformis which are poisonous. Species commercially cultivatedall over the world during summer months includes P. flabelltus, P. sajor cajo, P. sapidus, P.membranaceous,P.citrinopileatus, P.eous etc. and those produced during winter areP.ostreatus, P.florida, P.cornucopiae, P.fossulatus, P.eryngii etc.
5.4Cultivation Technology
The procedure for oyster mushroomcultivation can be divided into following four steps:
(i)Preparationor procurement of spawn
(ii)Substratepreparation
(iii)Spawningof substrate
(iv)Cropmanagement
5.4.1Spawn Preparation
A pure culture of Pleurotus sp. is needed for inoculationon sterilized substrate. It takes 10-15 days for mycelial growth on cereal grains.It has been reported that jowar and bajra grains are superior over wheatgrains.
5.4.2Substrate Preparation
Oyster mushroom can be cultivated on a large number of agro-wastes havingcellulose and lignin which helps in more enzyme production of cellulose that iscorrelated with more yield. These include straw of paddy, wheat and ragi, stalkand leaves of maize, millets and cotton, used citronella leaf, sugarcanebagasse, saw dust, jute and cotton waste, dehulled corncobs, pea nut shells,dried grasses, sunflower stalks, used tea leaf waste, discarded waste paper andsynthetic compost of button mushrooms etc. It can also be cultivated by usingindustrial wastes like paper mill sludges, coffee byproducts, tobacco waste,apple pomace etc.
The popular methods of substratepreparation are:
·SteamPasteurization;
·HotWater Treatment;
·SterileTechnique (Till method);
·Fermentationor Composting; and
·ChemicalSterilization.
5.4.3Spawning of Substrate
Freshly prepared (20-30 days old)grain spawn is best for spawning. Old spawn (3-6 months) stored at roomtemperature (at 20-300 C) forms a very thickmat like structure due to mycelium aggregation and sometimes young pinheads andfruit bodies start developing in the spawn bottle itself. The spawning shouldbe done in a pre-fumigated room (48hrs.with 2% formaldehyde).
5.4.4Crop Management
(A)Incubation
Spawned bags, trays or boxes arearranged in a dark cropping room on raised platforms or shelves for myceliumcolonization of the substrate. Although mycelium can grow from 10 to 330C, but the optimum temperature for spawn running lies between 22 to 260C.
(B)Fruiting
When the mycelium has fullycolonized the substrate, the fungus is ready for fruiting. Contaminated bagswith moulds may be discarded while bags with patchy mycelial growth may be leftfor few more days to complete mycelial growth.
While various species requiredifferent temperature regimes all require high humidity (70-85%) duringfruiting. Frequent spraying of water isrequired in the cropping room depending upon the atmospheric humidity. Fruit body produced under humid conditions(85-90%) is bigger with less dry matter while those developed at 65-70%relative humidity are small with high dry matter.
CO2 concentration during croppingshould be less than 600 ppm. or 0.6%. Sufficientventilation has to be provided during fruiting.
5.5Plant Protection Measures
5.5.1 The crop is suspect to attacks from flies (sciarid, cecid) spring tails and mites. Timely spraying with insect specific insecticides is needed.
5.5.2Thecrop is prone to fungal diseases. Severalcompetitor moulds e.g. Aspergillussp., Cladosporium sp. and Fusarium sp., Rhizopus sp. have been reported to occur in the substrate used forcultivation. Spraying with Bavistin orBenomyl is a recommended control measure.
5.5.3Thecrop is also subject to diseases like yellow blotch, brown spot and bacterialrot, control measures which are needed include:
·Proper management oftemperature and humidity during growing period.
·Regular application ofchlorinated water containing 100 – 150 ppm of freely available chlorine at aninterval of 3 – 5 days
·Application ofoxytetracycline and streptocycline.
5.6Harvesting and Yield
The right shape for picking can bejudged by the shape and size of the fruit body. The fruit bodies should be harvested before spore release, bytwisting so that the stubs are not left on the beds (straw). It is advisable topick all the mushrooms at one time from a cube and the next flush will appearat one time.
More than 500 kg. of fresh mushroomsper ton of dry wheat or straw can be obtained in case of crop produced in 45-60days.
6.POST HARVEST MANAGEMENT
6.1Storage
(A)Short-term Storage
Fresh mushrooms are packed in perforated polythene bags which aredirectly sent to the local market situated nearby. Freshly harvested mushroomscan be stored at low temperature (0-50 C) for 1-2 weeks without lossin quality in case it is to be sent to the distant markets.
(B)Long-term Storage
Dried mushroom with 2-4% moisture,can be stored for 3-4 months in sealed pouches without any change in taste. Thedried produce can be rehydrated in luke warm water (40-500 C) within20-30 mins. giving 80-90% of original weight.
6.2Packing and Transportation
Fresh mushrooms are packed in perforated polythene bags. Poly pouches containing crushed ice andoverwrapped in paper are put in trays/baskets which are then covered with thinpolythene sheet with sufficient perforation for proper aeration. The pre-packedpouches (250 or 500 g.) can be transported by roadways in trucks, busesdepending upon the quantity to be transported.
6.3Marketing
Domestic marketing does not pose aproblem at present because only small quantities are being traded. As production develops, marketing promotionmeasures will need to be undertaken to bolster the demand.
Export potential exists and needs tobe taken advantage of by organizing cooperatives of producers linked tocommercial units for processing fresh mushroom into dehydrated powder forexport.
7.SOURCES OF TECHNOLOGY
(i)NationalCentre for Mushroom, Chambaghat, Solan, Himachal Pradesh-173213, [Tel: (01792) 30451,30767]
(ii)PlantPathology Division, Dr. Yashwant Singh Parmar, University of Horticulture &Forestry, Solan, Nauni – 173230, Himachal Pradesh,
[Tel: (01792) 225 2315,225 2344]
8.ECONOMICS OF A SMALL SCALE MODEL
8.1Highquality commercial cultivation of the crop even on a small scale is a viableproposition as it is in good demand both in domestic and foreign markets. The economics of a small unit with annualproduction of 400 kg is brought out below:
Costs & Returns:
8.2Thecost components of such a model along with the basis for costing are exhibitedin AnnexuresI. A summary is given in thefigure below. Inclusive of 5%contingencies, the project cost works out to around Rs.50 thousand.
(Rs. In thousands)
| Project Cost | Amount |
| Land & Site Development | 21.47 |
| Building | 15.00 |
| Plant & Machinery | 11.90 |
| Contingency | 1.42 |
| Total | 49.79 |
8.3Themajor components of the model are:
·Land Acquisition & Development: (Rs. 21.47 thousand):On an average the cost of land can be put at Rs. 20 thousand in ruralareas/forest areas in States like Uttaranchal, NE Hilly States etc.
·Building (Rs. 15.00 thousand): This is the cost of high density polythenesheet growing room of 300 sq.ft.
·Plant & Machinery (Rs. 11.90 thousand per annum): Thisis the cost of setting up a sprayer room acquiring galvanised tubs, iron racksand thermometers.
8.4Recurring Production Cost (Rs. 6.83 thousand): Recurring production costs are brought outin AnnexureII. The main components are rawmaterial like wheat straw or rice bran, chemicals, cost of power & waterand packaging material etc. Labourcosts have been computed at Rs. 80 per man-day. These can, however, vary from location to location depending uponprevailing wage level or minimum statutory wages fixed. Recurring costs work out to Rs. 6.83thousand per annum.
Returns from the Project:
8.5Theyield from this unit would be 400 kgs. per annum. Valued at Rs. 40 per kg. the gross return would be Rs. 16thousand per annum. Annexure III gives profitabilitycalculations.
Project Financing:
8.6Balance Sheet:The projected balance sheet of the model is given at AnnexureIV. There would be threesources of financing the project as below:
Source Rs.Thousand
Farmer’s share 24.9
Capitalsubsidy 10.0
Termloan 14.9 Total 49.8
8.7Profit & Loss Account: Annexure V presents the cash flow statement and AnnexureVI projects the profit and loss account. Gross profit works out to Rs. 9.2 thousand per annum.
8.8Repayment of Term Loan: The term loan will be repaid in 11equated 6 monthly installments of Rs.1.36 thousand with a moratorium of 12months. (vide Annexure VII).The rate of interest would have to be negotiated with the financingbank. It has been put at 12% in the model.The repayment schedule is given in Annexure VII-A.
8.9Depreciation calculations are given in AnnexureVIII.
8.10IRR/BCR:The viability of the project is assessed in Annexure IX over a period of 10 years. The IRR works out to 17.14 and the BCR to 1.1.
8.11The Debt Service coverage ratio calculations are presented in AnnexureX. The average DSCR works outto 2.42.
8.12Payback Period:On the basis of costs and returns of the model as assessed above, thepay back period is estimated at 6.36 years (vide Annexure XI).
8.13Break-even Point:The break even point will be reached in the 3rd year. At this point fixed cost would work out to 58.1%of gross sales - vide Annexure XII.
