Effect,of,Different,Mycelium,Maturation,Conditions,on,Auricularia,auricula-judae,Fruiting:on behalf of

　　Institute of Microbiology, Heilongjiang Academy of Sciences， Harbin, Heilongjiang 150010, China
　　Maturation of Auricularia auricula-judae mycelium after the growth substrate had been fully colonized was carried out at different temperatures (17 ℃, 25 ℃ and 33 ℃) for different times (10 d, 20 d, 30 d and 40 d) and the effect of the different conditions on fruit body quality and yield was evaluated. Earliest appearance and highest formation rate of small fruit bodies, most rapid fruit body growth, and highest fruit body quality and yields, were recorded when mycelia were incubated at 25 ℃ for 20 d or 33 ℃ for 20 d. Adoption of optimal mycelia maturation conditions with respect to temperature and duration had a pronounced effect on the quality and yield of A. auricula-judae fruit bodies. Taking into account the overall costs of production, these were determined to be 25 ℃ and 20 d, respectively.
　　Auricularia auricula-judae; mycelium maturation; fruiting characteristics
　　Auricularia auricula-judae is an edible fungus cultivated in China and an important component of several mushroom products［1］. In recent years, cultivation of A. auricula-judae has become an important component of the local economies of mountainous and forests regions［2］. Good growth of A. auricula-judae mycelium is the key to successful bag cultivation, and includes the spawn-running stage (from inoculation to full colonization of the substrate) and a maturation stage (from full colonization to primordia/small fruit body formation) during which, under suitable conditions, the mycelium continues to grow. In general, the greater the mycelium biomass, the higher production of fruit bodies, so that optimal maturation conditions are important for obtaining high mushroom yields. Although considerable research has been undertaken to determine the optimal conditions for maturation of Hypsizygus marmoreus, Pleurotus eryngii and P. nebrodensis mycelium［3-6］, relatively little research of this nature relating to A. auricula-judae has been reported［7］. In this study, maturation stage mycelium of A. auricula-judae has been incubated at different temperatures for different times and the effect on fruiting determined. Our data will provide a reference for optimal maturation of fungal mycelium in cultivation bags during large-scale mushroom production.
　　1 Materials and Methods
　　1.1Test strain
　　A. auricula-judae, strain “Black 29”, was provided by the Microbiology Institute Culture Collection Center, Heilongjiang Academy of Sciences.