Photoautotrophic Growth of Pleioblastus Pygmaea Plantlets in Vitro and Ex Vitro As Affected By Types of Supporting Material In Vitro

Sasa (Pleioblastus pygmaea Miff., cv. Oroshimatiku) has been used as a ground-cover plant because it keeps the ground green throughout the year and prevents soil erosion. Sasa, which rarely flowers, can be micropropagated under artificial light for mass production of transplants. In this study, a micropropagation system for sasa has been developed. The processes are 1) an in vitro propagation period, 2) an in vitro growth period and 3) an ex vitro acclimatization period. The growth of plantlets was examined under six culture conditions: with combinations of sugar-containing or sugar-free medium and one of two types of supporting material (plastic net and vermiculite) or no supporting material. All plantlets were grown under relatively high photosynthetic photon flux (PPF) and CO2-enriched conditions during the growth period. Plantlets grown on sugar-containing medium without supporting material under relatively low PPF and CO2 non-enriched conditions were used as a control. The plantlets grown photoautotrophically with vermiculite during the in vitro growth period showed enhanced growth during the ex vitro acclimatization period, while the plantlets of the control wilted during that period.