MUSHROOM

Milky mushroom

The milky mushroom (Calocybe indica) is a potentially new species to the world mushroom growers. It is a robust, fleshy, milky white, umbrella like mushroom, which resembles button mushroom. The species is suitable for hot humid climate and can be cultivated indoor in high temperature and high humidity areas. It grows well at a temperature range of 25-35°C and relative humidity more than 80%. Milky mushrooms can be cultivated throughout the year in the entire plains of India.

The cultivation technology is very simple, involves less cost and no special compost is needed for the cultivation. The cultivation process resembles that of oyster mushroom but for the additional process of casing. The mushroom can be harvested from 24-28 days after spawning and the total crop cycle is only 45-50 days. Most importantly, the milky mushroom has an extended shelf life of 3-5 days compared to other cultivated species, making it more amenable to handling, transportation and storage. So, there is a growing interest among the farmers towards milky mushroom. The production technology of milky mushroom is outlined here:

Substrates

Milky mushroom can be cultivated on a wide range of substrates like, paddy straw, maize stalks, sorghum stalks, pearl millet stalks, palmarosa grass, vetiver grass, sugarcane baggase, soyabean hay, groundnut haulms etc. However, for commercial production paddy straw is the best substrate.

Pasteurisation/sterilization

Polythene bags of 60x30 cm or 75x45 cm size are used for bed preparation. Chaffed paddy straw bits of 3-5 cm length are soaked in cold water for 4-5 hours. After draining the excess water, the straw bits are boiled for 45-60 minutes in a separate drum. Though hot water treatment is the safe and best method of sterilization, steam treatment or chemical treatment with a solution containing carbendazim and formalin can also be followed. After treatment, the substrate is shade dried to remove excess moisture before bed preparation. At the time of bed preparation the substrate should contain around 60% moisture (can be tested by squeeze method).

Spawn requirement and availability

Milky mushroom is also propagated through spawn. Spawn produced with sorghum grain/paddy chaff as substrate is most commonly used. With each bottle of spawn 2 cylindrical beds can be prepared. Quality spawn materials are available from xxxxxxxxxxx.

Bed preparation

Cylindrical beds are prepared following layer method of spawning. A layer of straw is laid and sprinkle one tablespoon full of spawn over the filled straw around the peripheral region. A second layer of processed straw is filled and spawned as above. Repeat the process until the soaked straw is finished. Every time before spawning, press the straw with hand for making it compact. Finally the bag is close tightly with twine and the beds are incubated for spawn running under semi-dark condition in a clean room. Spawn run will be completed in 12-15 days at 30-35°C.

Casing

Unlike oyster mushroom cultivation, milky mushroom production involves an additional process called casing. After the completion of spawn run, the cylindrical beds are cut horizontally into two equal halves. Apply casing soil on to both halves to a height of 1-2 cm. The casing soil is prepared by steaming garden soil (clay loam, pH around 8.0) for one hour.

Cropping

After casing, the beds are to be incubated over racks in a partially sunken chamber lined with blue coloured high-density polythene sheet as roofing material. Optimum relative humidity of 80-95%, room temperature of 24-28°C and light intensity of about 1600 –3200 lux should be maintained in the cropping room. Proper ventilation for gaseous exchange is also essential in this chamber. The beds are regularly sprayed with water to maintain 50-60% moisture level on the casing surface. Pinheads appear in 8-10 days after casing and the first harvest can be made in 6-8 days after pinhead formation. After obtaining the first harvest the casing medium is gently ruffled, slightly compacted back and sprayed regularly with water. Second and third harvest may be obtained within 45-50 days of bed preparation. Then the beds are removed and fresh beds may be kept for cropping.

Yield

On an average single mushroom weighs 55-60 g and mean yield is 356 g/bed (contains 250g of paddy straw on dry weight basis), which accounts to 143% bio-efficiency. Milky mushroom is a rich source of protein with protein content of 32.3% and fetches high market price compared to oyster mushrooms. It is highly suitable for drying, canning, soup powder preparation and pickle making.