Rapid and optimized micropropagation of Dendrobium anosmum Lindl. (unscented dendrobium) utilizing stem nodal explants

Efficient micropropagation is vital for mass production and conservation of orchids. The objective was to determine the most effective combination of cytokinin 6-benzyladenine (BA) and the auxin α-naphthaleneacetic acid (α‑NAA) for enhancing shoot number, shoot elongation, leaf proliferation, and biomass accumulation of Dendrobium anosmum Lindl. Eighty stem nodal segments were cultured on Murashige and Skoog (MS) medium across a factorial design testing four concentrations of BA (0, 0.5, 1.0, or 2.0 mg/L) combined with two concentrations of α‑NAA (0 or 0.5 mg/L). The combination of 1.0 mg/L BA and 0.5 mg/L α‑NAA (Treatment 2) was determined to be optimal for shoot growth and development after 56 days of culture. This treatment consistently produced the highest mean values for all measured growth parameters, including shoot number (3.15), shoot length (0.87 cm), leaf number (5.40), and fresh weight (129.00 g). These results confirm a successful synergistic interaction between the two plant growth regulators. The combination using 1.0 mg/L BA and 0.5 mg/L α‑NAA provides a robust and highly efficient method for the rapid, large-scale production of D. anosmum .