Effect of Storage of Spawn on Mycelial Growth, Fruit-Body Formation and Mycelial Constituents of the Shiitake Mushroom(Lentinus edodes)

The effects of short periods (15-200 days) of either refrigerated or room temperature spawn storage on the mycelial growth, fruit-body yield, chemical constituents and enzyme activities of the mycelia of three strains of Lentinus edodes were investigated. No significant decrease in the mycelial growth and fruit-body yield was observed under storage for 200 days at 4°C, 160 days at 15°C or 60 days at 24°C. Mycelial growth increased upon spawn storage for 60-110 days at 4°C or 15°C. These effects were observed in all strains tested. The fruit-body yield increased on storing the spawn for 30 days at 15°C. However, storage of the spawn for relatively longer periods (160-200 days) at low temperature (4°C, 15°C) decreased the formation of morphologically normal fruit-bodies. In contrast, normal fruit-body formation increased upon storage for shorter periods at 24°C compared with the not-stored spawn (control) . Total sugar in mycelia after incubating the stored spawn decreased significantly, whereas the protein and free amino acid content did not show any decrease. Proteinase activity in mycelia after incubating the stored spawn did not differ significantly. However, amylase, β-1, 3-glucanase and trehalase activity decreased markedly upon storage of the spawn.