In the case of the single inoculation with Graphostroma platystoma to the branch segments, stromata were formed between 15-35℃, and the rate of stroma formation increased in proportion to the temperature between 15℃ and 30℃. The optimum stroma formation was at 30℃. In the case of the simultaneous inoculation with G. platystoma and Lentinula edodes, the rate of stroma formation and the rate of sectional occupation were high at 30℃ but were remarkably low at 25℃ and below. The water content of the branch segments was adjusted between 21% and 47% by adding water to the container and immersing the branch segments into water. In the case of single inoculation with G. platystoma, stromata were formed under a water content of 21% and above, and the rate of stroma formation was highest around 30%. In the case of simultaneous inoculation with both fungi, both the rate of stroma formation and sectional occupation were the highest at 21%, and decreased in inverse proportion to the water content of the branch segments. Between 10℃ and 30℃, L. edodes invaded the areas which G. platystoma was occupying and replaced it. L. edodes invaded these areas rapidly between 15-25℃ but rather slowly at 10℃ and 30℃.

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The effect of corn fiber (CNF), which is a by-product of the wet corn milling process of the production of corn starch in factories on the fruit-body formation of edible mushrooms in a sawdust-based cultivation, was examined. In Lentinula edodes, however, the increase in fruit-body yield was not observed, but the pileus diameter of fruit-body tended to enlarge with added CNF. In Pleurotus ostreatus and P. cornucopiae, fruit-body yield increased at 1.2-1.6 times by using CNF. In addition, the cultivation period was shortened for the 2nd-1lth day compared to that of the control without CNF. From these results, we see that CNF is a useful culture material for sawdust-based cultivation. Furthermore, CNF is effective in producing the fruit-body which increases yield, shortens the cultivation period and increases the quality of mushrooms.

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The effect of light illumination wavelengths on mycelial growth and synnema formation of Isaria japonica was examined using light-emitting diode (LED) with four different wavelengths: blue (wavelength: 460nm); green (520nm); yellow (592nm); and red (630nm). No significant differences were seen in the elongation rate of mycelia among the four tested groups. However, a dry weight of mycelia was significantly increased in the groups exposed to a blue or green LED as compared to the control (grown in darkness). When mycelia were grown under a yellow or red LED, no synnema formed. Blue and green LEDs were more effective in the induction of the synnema formation, and they also resulted in higher yields of synnema. However, a larger number of conidiospores formed under illumination with a blue LED. Therefore, we conclude that a green LED is optimal for both a higher yield of synnema and a suppression of conidiospore formation in commercial cultivation.

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