Optimizing the potential utilization of bioreactors for the mass propagation of Indonesian Dendrobium varieties

The study focuses on two Indonesia Dendrobium varieties, D. Dian Agrihorti (DDA) and D. Syifa Agrihorti (DSA), which have potential to be commercialized, but face limitations on the availability of qualified seedlings sustainably. The research aimed to establish an in vitro propagation protocol using a Temporary Immersion System (TIS) to produce high-quality seedlings efficiently. Various factors, including varieties, media, plant growth regulators, anti-phenol compounds, organic additives, and TIS settings, were investigated using the basal part of the plantlet as the explant source. Key findings revealed that DDA outperformed DSA across all observed variables. In the initiation phase, basal plantlets cultured in Murashige and Skoog (MS) medium supplemented with 1.0 mg L-1 thidiazuron and 0.5 mg L-1 N-6 benzylaminopurine enhanced embryogenic callus (EC) formation, with a 13.5-day initiation period, 72% potential explant growth, 0.41 cm callus size, and a 3.45 rate of multiplication. During the proliferation stage, the addition of 150 mg L-1 ascorbic acid (AC) and the application of a TIS with a 30-minute dry period and a 15-minute wet period resulted in a 515.5% increase in EC fresh weight for DDA accompanied by a 6.16 multiplication rate. Regeneration of shoots was achieved using a Vacin and Went medium with 150 g L-1 banana extract, yielding 29.2 shoots per clump. Subsequent rooting of the shoots in 2 g L-1 Hyponex® medium with 20 g L-1 sugar and 2% AC proved successful. Acclimatization of plantlets with Cycas rumpii bulk demonstrated a 100% survivability rate. The established propagation protocol for DDA holds significant potential for application to other Dendrobium varieties, offering a sustainable and efficient method for meeting commercial demands in the Indonesian market.