Straw mushrooms (Volvariella volvacea Singer)- a type of edible tropical mushroom can be grown cheaply using rice straw or banana leaves as bedding material. Dr. Aliebusan from the National Institute of Science and Technology, National Science Development Board (NIST-NDB) recommends this method since it is cheap and easy to adopt.
Straw mushrooms flourish almost simultaneously along the sides of the growth substrate. Within two to three days the color changes from white to black, then to brown, and gradually fades as the mushrooms grow larger. Some strains are dark brown or black. They may be chesnut-or egg-shaped.
The young mushroom is covered initially with a thin membrane called the volva. As the mushroom develops, the stem or stipe elongates, gradually pushing the cap upwards, which causes the volva to rupture and remain at the base of the stem. The still unopened mushroom cap is further pushed up to a height of about 6 to 10 cm. Once the stem reaches its maximum height, the cap starts to expand. Initially, the gill are white, but they turn brown once mature basidiospores.
The beds should not be watered in the first five days after bed preparation. During the dry season, the beds may be watered minimally but generously on the sixth or seventh day after planting. The beds should not be watered once a day until the mushrooms are as big as pin-heads. During the rainy season, only the sides of the beds should be watered. Button mushrooms can be harvested 10 to 14 days after planting. The harvest usually lasts for three days. This is called the “first flush”. Average daily production during this period is 1.2 kg. The next harvest is done after five to seven days, The second harvest is much smaller at 0.42 kg. This manner of production may continue for a month or even longer.
During harvest, the mushrooms must be carefully pulled out whole from the bed. Any portion left behind will decay and result to bacterial soft-rot affecting the succeeding crop, and drastically reducing the yield.
Both bed types need lots of bedding materials. Yields depend on the volume of bedding material used. A standard four-meter, six-layer bed could yield up to 7 kg of buttons or 12.6 kg of fully mature mushrooms.
Scientists recommend that farmers use this simple technology in their own backyards. If not for money, they can always grow it for their own consumption. Mushrooms are very nutritious containing a “cocktail of nutrients”- vitamins, minerals, chitin and protein that everyone needs. Not only that, it has no cholesterol and thus, is very good for the heart.
Mushroom production technology for rural development by R.V Alicbusan. National Institute of Science and Technology, National Science Development Board, Manila, Philippines.
By: Junelyn S. dela Rosa, BAR Chronicle, January 2002 Issue (Vol. 3 No. 1-2)