試管內培養基成分與無土介質對鐵線蕨孢子發芽與原葉體生長及配子體發育之影響

Spore Germination, Prothallus Growth and Gametophyte Development of Adiantum capillus-veneris under in vitro and Soilless Culture Conditions

取成熟而新鮮之鐵線蕨孢子，研究試管內之培養基成分與無土介質對孢子發芽與原葉體生長及配子體發育之影響。試驗結果顯示全量MS處理播種40天後之發芽率為82.5%，而1/10和1/4MS低鹽類濃度處理發芽率為65%。繼代培養以全量MS培養基處理之原葉體鮮重較重褐化較少；1/10和1/4MS處理之原葉體鮮重較低且嚴重褐化。不添加蔗糖處理者原葉體鮮重最低，2～4%蔗糖濃度處理使原葉體鮮重增加。不添加活性碳處理者培養一個月後，每廣口瓶內約有4.2g原葉體，而添加活性碳1和2g/L處理者，瓶內原葉體鮮重雖分別僅為31和2.4g，但可抑制原葉體褐化。於光學顯微鏡和解剖顯微鏡下觀察鐵線蕨孢子多在環帶內發芽，試管內之原葉體僅分化藏精器，而播種於無土介質之配子體則正常分化有藏精器和藏卵器。試管內培養之原葉體可增生為多原葉體，將試管內之原葉體持續繼代培養則形成羽片不易展開之孢子體；如將試管內之原葉體移於無土介質50天後可形成羽片發育正常之孢子體。

Spore germination and gametophyte development responses of Adiantum capillus-veneris were studied in various medium composition in vitro and in soilless culture. Spore germination of 82.5% after sowing for 40 days was measured in MS basal salt medium, compared to 65% in 1/10 or 1/4 MS treatments. Prothallus fresh weight was increased by MS subculture treatment, while decreased fresh weight and severe prathallus browning were seen in 1/10 or 1/4 MS treatments. The fresh weight of prthallus increased as supplement of sucrose increased from 0 to 2%, after which (2~4%) it remained constant. No addition of activated charcoal resulted in prothallus fresh weight of 4.2g per sample, greater than 3.1 and 2.4g in supplementary 1 and 2g/L activated charcoal, respectively. Major spores germinated within the annulus as observed by using a stereomicroscope and a dissecting microscope. Both antheridia and archegonia were differentiated when cultured in soilless medium, while only antheridia were seen in aseptic culture. Results here suggest that in vitro three-dimensional thalli should be transferred to soilless medium, and thereafter would produce sparophytes after 50 days of transferring.