Culture condition for gametophyte and sporophyte masspropagation of bamboo fern (Coniogramme japonica) using tissue culture

This study was conducted to investigate the optimal culture method for gametophyte and sporophyte propagation in Coniogramme japonica (Thunb.) Diels, which can be used in various fields. The propagation of prothallus were cultured in 1/4 - 1 Murashige and Skoog medium and Knop medium for 10 weeks. The results indicated that the fresh weight of prothallus was the highest (14.5 g) in 1MS medium. Subsequently, various concentrations of sucrose, activated charcoal and nitrogen source were also added to 1MS medium and cultured for 8 weeks. The results provided that the sucrose concentration was 3% and the fresh weight of prothallus was the highest 10.8 g. According to the concentration in the range of 8.8 ~ 10.8 g, in the case of activated charcoal, the four treatments showed no significant difference. The nitrogen source was added at a concentration of 30, 60 and 120 mM with the ratio of NH4 + : NO3 - being 1 : 2. As a result, the fresh weight of all treatments increased to similar level but there was no significant difference. We investigated sporophyte formation according to soil type and the highest number of sporophytes at 228.0 was formed in soils mixed with horticultural substrate and decomposed granite at 2 : 1 (v : v). On the other hand, sporophyte was not formed in soils containing peatmoss except for the one with peatmoss and decomposed granite at 2 : 1 (v : v).