Paddy straw mushroom

Paddy straw mushroom (Volvariella sp.)/ Straw mushroom or the Chinese mushroom or Warm mushroom is third most important cultivated mushroom in the world is well known for its pleasant flavor and taste. In Odisha, it is most popular and commonly grown mushroom.

Steps for cultivation of Paddy straw mushroom

Spawn preparation: The ready-to-mix spawn (seed) can be prepared on the chopped paddy straw. The fresh dried paddy straw is to be cut (2.5 to 5.0 cm long) and soaked in clean water for 2-4 h in a drum. The soaked straw is drained on sieve for 30 min, followed by mixing of CaCO₃ and CaSO₄ @ 2.0 and 1.0%, respectively on dry weight basis. Thoroughly mixed spawn substrate is filled up to half portion in polypropylene (PP) bags (25 cm x 12 cm) of 100 gauge thickness. The PP bags are closed by creating neck on top of the bags with the help of a plastic ring, plugged with non-absorbent cotton and to be sterilized at 22 pound square inch pressure for 1.5 hour in an autoclave. After sterilization, the bags are put under UV light for 30 minutes on laminar flow bench. The contents in bags are mixed by shaking once or twice and inoculated with 20-30 grains of master spawn prepared by following the same protocol as described above just by replacing paddy straw with wheat grains as the basal ingredient and PP bags with empty glass glucose saline bottles as the container. The inoculated bags are incubated at 32 ± 2°C for 8 days in BOD incubator. The fully colonized bags are removed from the incubator and placed at the ambient temperature of 16-25oC for chlamydospores development and storage till further use.

Cultivation method:

Prepared paddy straw bundles of size 60 cm x15 cm (0.4 to 0.5kg weight) by discarding the top portion of paddy straw.
Immerse the bundles in clean water for 12-18 hours in a cemented/polythene tank.
Drain out the excess water by placing the bundles on raised platform.
Make bed by placing 4 bundles side by side.
Put one third of mushroom spawn along the four sides of bed leaving margin of 8-10 cm from edge.
Sprinkle red gram powder or mixture of red gram power and rice bran over the spawned surface.
Form second, third and fourth layer by intermittent spawning between first and second, second and third and third and fourth.
Use one bottle of spawn and 200 g of red gram powder per bed.
Press the beds from the top and covering with semitransparent plastic sheet for maintaining required humidity (80-85%) and temperature (30-35°C) .Remove the plastic sheet after 7-8 days of spawning.
Harvest the first flush of mushroom at egg stage which will ready after 4-5 days of removal of plastic sheet. First flush normally last for 3-4 days and contributes 70-90% of total production.
With maintenance of temperature and humidity second flush of mushroom contributing 10-30% of total production can be harvested after 3-4 days of first flush.
Biological efficiency is around 20-25% and farmers will harvest 1.5 kg of mushroom per bed.