SPAWN MANIPULATION FOR PLEUROTUS EOUS

The spawn is nothing but the seeds of mushroom. Its making has been primary concern in mushroom industry which is achieved by developing mushroom mycelia on supporting medium under controlled environmental conditions. In almost all cases the supporting matrix is sterilized grain which is preferred due to its bio-chemical properties and practical performance over others. Traditionally, wheat grains are used as spawn substrate. Unfortunately, the ever increasing demand of this grains for human consumption leaves little scope for its use in spawn making. A number of less popular grains can be used to prepare mushroom spawn. Keeping this in mind, we have screened various cereals viz., Barley (Hordeum vulgare), Maize (Zea mays), Oat (Avena sativa) and millets, viz., Italian millet (Setaria italica), Pearl millet (Pennisetum typhoides), Little millet (Panicum miliare) and Sorghum (Sorghum vulgaris) against traditionally used wheat grain  (Triticum aestivum) for making efficient planting spawn of pink oyster mushroom Pleurotus eous.

                                     Methodology

This work was carried out in Mushroom Research laboratory, K.S.S. P.G. College, Ayodhya, Faizabad (U.P.), India. The mother spawn was purchased from the Mushroom section of Plant Pathology Department, Chandra Shekhar Azad University of Agriculture and Technology, Kanpur (U.P.) India. The planting spawn was developed by the method given below. 

Grains for making spawn

One kilogram of cereals and millets is washed separately and water soaked overnight. On the following day, these were washed again and in water for at least 10-15 minutes until they expanded and not broken. The water was then drained out and boiled grains were allowed to cool. Two per cent gypsum and four per cent calcium carbonate was added to grains thoroughly. The mixture obtained was loosely packed in spawn containers and autoclaved at 15 lbs (121°C) for 1-1½ hour. After autoclaving, the containers were removed from autoclave. Next day these were inoculated with the 10-15gm of mother spawn of fungus within aseptic conditions and incubated at 24-25 °C until mushroom mycelium covered the grain substrate.   

Spawn developed on different grain substrate

 Once spawn was prepared, the pastuerized wheat straw was seeded with it @ 5% w/w on dry wt basis in  multilayered  manner (3). The bags was then incubated in cultivation room at 22-30°C for mycelial growth. Once the mycelia has completely colonized the wheat straw substrate, the polythene covering is turned off and relative humidity is maintained 85-95 per cent with the help of humidifier. The mushrooms are harvested by gently twisting and pulling them from the bags. Completely randomized design (CRD) was employed for this experiment. Yield data was statistically analysed. The critical difference (CD) was worked out at five per cent probability level.
                                         Results
For making of planting spawn, the basal medium (grain) is inoculated with mother spawn of mushroom.  The grains act as a reservoir of carbohydrates which offer sufficient nutrition for mycelial growth and provide vehicle for the eventual even distribution of mushroom inoculant. The major disadvantage of small grains like Italian and little millet is presence of less food material in their endosperm and greater surface area in a given amount as compared to larger grains. Thus, mushroom mycelium  took more time to establish and run over the surface of grains resulting delayed spawn development. (Table) 

Table.  Efficiency of different grain spawn on yield performance of Pleurotus eous

 After seeding the  growing mediums, grain spawn allows a quick spreading of mycelium from a small propagation center because small grains like Italian and little millets provide more point of inoculum per gram of spawn, they covers the substrate sooner and gives early fruiting than larger grains i.e. maize. Medium sized grain also seems better in aforesaid terms. 
The yield variation shows that fruiting of mushroom is greatly influenced by spawn substrate. In our investigation, oat, barley and sorghum grains were found more productive than others. Statistically, they were at par to each other. (See original)

Cite this as: Siddhant, Swapnil Yadav and C.S. Singh (2013). Spawn and Spawning Strategies for the Cultivation of Pleurotus eous (Berkeley) Saccardo. International Journal of Pharmaceutical and chemical sciences. 2(3):1494-1500