Sawdust-based cultivation of some mushrooms using unutilized wood resources

Summary In the present study, a possibility of sawdust-based cultivation of some mushrooms was investigated by using thinned softwoods with or without smoke-heating treatment, and by using wood residuals and wastes largely released from wood industry. Influences of physical condition such as air permeability and water content in sawdust bed on the yield of fruiting bodies were examined extensively. In addition, a possibility of sawdust-based cultivation of some mushrooms was also investigated by using other lignocellulosic wastes. The results obtained in the present study are sumnrarized as follows: 1. Sawdust-based cultivation of mushrooms using smoke-heated softwood thinned In this experiment, screening of maitake strains suitable for sawdust-based cultivation using Japanese cedar (Clyptomeria japonjca) was attempted. To select strains suitable for Japanese cedar substrate in sawdustbased cultivation of maitake (Grifola frondosa), the mycelial growth and yield of fruiting bodies were examined using 38 strains provided from 12 mushroom companies. In almost all of the strains, the mycelial growth was greater in the smoke-heated substrate than in the control. In all strains, however, Japanese cedar substrate smoke-heated gave smaller mycelial growth in test tubes than beech (Fagus crenata) substrate. It is of interest to note that three strains gave relatively large yields of fruiting bodies when smoke-heated Japanese cedar was used, although the yields obtained were less than those of beech substrate. This fact suggests a possibility of maitake cultivation using these strains. However, it is necessary to improve not only the physical conditions, such as wood meal size and moisture content but also the chemical conditions which influences mycelial growth such as nutritional additives and inhibiting substances, to obtain the sufficient yield of fruiting bodies. 2. Effects of physical conditions of sawdust bed on fruiting 2.1 Effects of corncob meal addition to media on the mycelial growth and fruiting in sawdustbased cultivation of shiitake The effects of corncob meal addition to the medium were investigated on the yield of fruiting bodies in sawdust-based cultivation of shiitake (Lentinula edodes) using smoke-heated Japanese cedar and Japanese larch ( Larix kacmpferi) sawdust, Both smoke-heated Japanese cedar and Japanese larch sawdusts remarkably promoted mycelial growth of shiitake with the increase in the amount of corncob meal added to the media. In shiitake cultivation using these sawdust, yields of fruiting body were most increased by the addition of 20% corncob meal, whereas addition of 10% and 30% corncob meal did not give large effects positively.