段木香菇樹種產菇試驗與段木香菇生產知識結構之研究-以屏東縣牡丹鄉為例

段木香菇為林下經濟正面表列之品項，亦是山村居民循環利用森林資源與獲取經濟收入之展現。本研究為以「適地適木」為前提，發掘部落合適之菇木樹種，並協助部落記錄與建立段木香菇生產之知識。於屏東縣牡丹鄉高士部落808地號，使用楓香(Liquidambar formosana)、杜英(Elaeocarpus decipiens)、印度栲(Castanopsis indica)、青剛櫟(Cyclobalanopsis glauca)、白匏仔(Mallotus paniculatus)與相思樹(Acacia confusa)等6種樹種進行香菇量與品質之比較。研究期間自2020年11月至2022年3月，共計1年5個月。於研究初期量測與記錄段木重量、含水率、樹皮與邊材厚度；並於香菇生產期間測量香菇產量、菇體性狀、顏色、復水比、保水力、質地與香菇感官分析，以供分析各樹種段木特性、產菇量與品質。研究結果顯示，各樹種段木重量與含水率於研究期間分別呈現下降與上升趨勢；樹皮與邊材厚度分別以印度栲0.84±0.21 cm與楓香8.45±2.07 cm最厚；產菇表現以杜英9.59 kg/m3最高；菌傘直徑以印度栲之鮮菇6.6±0.73 cm、乾菇4.31±0.87 cm最長；楓香鮮菇2.58±0.48 cm與乾菇1.88±0.48 cm之菌傘厚度最厚；菇體顏色以印度栲表現為淺且具有光澤；復水比與保水力分別以印度栲與青剛櫟香菇表現較佳；質地以青剛櫟鮮菇489.98±132.96 g/cm2與印度栲復水香菇223.11±54.56 g/cm2有較佳之彈性表現；香菇感官分析方面，以楓香、印度栲與青剛櫟之乾燥香菇與烹煮後香菇獲得較高之喜好程度，此外部落居民常以印度栲、楓香、青剛櫟與杜英等4種樹種進行段木香菇栽培，並認為段木香菇相較太空包栽培法之香菇，於氣味及口感最具差異性。綜合段木樹種試驗研究結果，本研究最終推論若考量短期收益與木材單位材積之香菇總收穫量，應選用杜英、青剛櫟段木為主要菇木樹種；若考量段木耐用程度、產菇年限與菇體外觀品質，則應選用楓香與印度栲段木為佳。段木香菇生產知識建立部分，本研究訪談牡丹鄉、達仁鄉菇農之段木香菇生產知識，以內容分析法萃取其中知識內容並繪製知識結構圖初稿，再經由焦點團體法邀請部落資深菇農共同討論及修訂知識內容，最終產出部落段木香菇生產知識結構圖，內容以三階層結構呈現。第一階層包含前置作業、植菌、立木與驚菌、採收與乾燥四項主要生產作業，第二、三階層分別呈現每一主要作業之細部工作項目、操作方式與技巧。本研究結果期可作為部落適地選擇菇木樹種參考，並作為段木香菇生產知識傳承與創新之基礎。

關鍵字

混農林業；內容分析；森林農作；知識管理；段木香菇

並列摘要

Wood log shiitake belongs to the positive list of Under-forest Economy, and it is also a manifestation of forest resources recycling and economic income for the mountain villagers. This study was conducted to identify suitable mushroom species for the tribe based on the premise of "suitable land and suitable wood", and to help the tribe record and establish knowledge of wood log shiitake production. We compared the quantity and quality of mushrooms among six species such as Liquidambar formosana, Elaeocarpus decipiens, Castanopsis indica, Cyclobalanopsis glauca, Mallotus paniculatus, and Acacia confusa in Lot 808, Gaoshi Tribe, Mudan Township, Pingtung County. The timeframe of this study ranged from November 2020 to March 2022, with a total of 1 year and 5 months. The weight, moister content, thickness of bark and sapwood for the wood logs were measured and recorded at the initial stage of the study. During the mushrooms production stage, mushroom yield, mushroom body properties, color, rehydration ratio, water holding capacity, texture, and mushroom sensory analysis were measured to evaluate the characteristics, yield, and quality of wood logs of each tree species. The results showed that the weight and moister content of various wood log species showed decreasing and increasing trends during the study timeframe. The thickest bark and sapwood were Castanopsis indica (0.84±0.21 cm) and Liquidambar formosana (8.45±2.07 cm), respectively; the highest mushroom production performance was 9.59 kg/m3 for Elaeocarpus decipiens; in terms of pileus diameter, the fresh mushrooms (6.6±0.73 cm) and dried mushrooms (4.31±0.87 cm) of Castanopsis indica were the longest; regarding the thickness of the pileus, the fresh mushroom of Castanopsis indica (6.6±0.73 cm) and the dried mushroom of Castanopsis indica (4.31±0.87 cm) were the thickest; as for the color of the pileus, Castanopsis indica presented the lightest and shiny appearance; Castanopsis indica and Cyclobalanopsis glauca mushrooms had the best rehydration ratio and water holding capacity; in terms of texture, Cyclobalanopsis glauca fresh mushrooms (489.98±132.96 g/cm2) and Castanopsis indica rehydrated mushrooms (223.11±54.56 g/cm2) had the best performance in flexibility. In terms of sensory analysis of mushrooms, the dried and cooked mushrooms of Liquidambar formosana, Castanopsis indica and Cyclobalanopsis glauca received a higher preference. Also, tribal folks often cultivate wood log shiitake with four species of trees, including Castanopsis indica, Liquidambar formosana, Cyclobalanopsis glauca, and Elaeocarpus decipiens. They believe that wood log shiitake has the most distinctive flavor and taste compared to the mushroom cultivated in bags with supplemented sawdust. According to the results of the experimental study on wood log species, this study concludes that Elaeocarpus decipiens and Cyclobalanopsis glauca should be selected as the main mushroom wood species if the short-term profit and the total mushroom harvest per unit volume of wood are considered. When considering the durability of the wood, mushroom production life and mushroom body quality, Liquidambar formosana and Castanopsis indica are preferred. To build up the knowledge of mushroom production, we interviewed mushroom farmers in Mudan and Daren villages. Using the content analysis method, the knowledge content was extracted and the first draft of the knowledge structure was drawn. The knowledge content was then reviewed and modified by inviting experienced mushroom farmers from the tribe through the focus group method. Finally, the knowledge structure graph of tribal wood log shiitake production was developed, with the contents presented in a three-level structure. The first level contains four main production operations: pre-production, planting, stumping and stunning, harvesting and drying. The second and third levels involve the detailed work items, operation methods and techniques of each major operation. It is expected that the results of this study may serve as a reference for selecting the appropriate mushroom species for the tribe and as a basis for knowledge transfer and innovation in wood log shiitake production.