In vitro propagation and long-term observation of acclimated plants in endangered tree fern Alsophila costularis

Alsophila costularis Barker (Cyathea costularis), an endangered tree fern with tree-like erect stem, attracts gardening enthusiasts as a special ornamental plant. In vitro propagation can be advantageous for germplasm conservation and commercial application of A. costularis. Here, we described in via spore culture green globular bodies (GGBs) system, well the long-term observation acclimated plants regenerated from GGBs. culture, low concentration mineral salt (1/8 MS) was beneficial sporophyte formation on gametophytes, but sporophytes per conical flask only 8 plantlets. GGB cytokinin thidiazuron (TDZ) essential induction multiplication. The maximum frequency (93.33%) obtained 1/2MS medium 2.0 mg/l TDZ by using juvenile explants, same optimal 1/4 MS supplemented 0.1% (w/v) activated carbon (AC) appropriate plantlet regeneration GGB, differentiation 100%, 42.40 plantlets could one piece height (4.64 cm) 1/2 AC. After 6 years acclimatization cultivation GGBs, plastic pots diameter 60 cm showed excellent vegetative reproductive growth, mature spores these produce sporophytes. Morphological histological demonstrated that GGBs structure consisted multiple single hair-like structures. One develop into plantlet. Establishment protocol costularis,