Physiological study of the wild edible mushroom leucocalocybe mongolica

Leucocalocybe mongolica (S. Imai) X.D. Yu & Y.J. Yao, a well-known edible and medicinal mushroom is endangered as its habitat is continually under threat from human activities, which has been lessening year after year. In this paper, the biological characteristics of the fungus of strain isolated from the wild fruit body were studied. For the screening of single optimal factor, carbon sources, nitrogen sources, inorganic salt and growth factor were tested for the mycelia growth rate. As a result, the fungus grew better on maltose, starch and cellobiose as the carbon sources; yeast extract, beef powder, beef extract as the nitrogen sources; K₂HPO₄ Fe₂(SO₄)³ as the inorganic salt; some decoctions such as of Pleurotus ostreatus, carrot, soybean sprouts as the growth factor. The orthogonal experiments with the above selected three conditions for each of the four factors were then performed and the optimal cultivation conditions were determined. A descending order of the impact for the four factors was growth factor > inorganic salt > nitrogen source > carbon source and the F-Test showed very significant difference among all the four factors. The optimal culture condition for L. mongolica was the combination of starch and beef extract, decoction of 2% carrot, no added inorganic salt. Based on this conclusion of the orthogonal experiment, the optimal medium in mycelium cultures was applied to temperature and pH experiments, anointed with pH=6.5 and at 25°C were suggested that good growth of mushrooms.