Investigations on micropropagation of orchid (phalaenopsis sp) in vitro conditions

In recent years, alongside traditional methods, biotechnological approaches have gained significant importance in the propagation and breeding of ornamental plants in Türkiye. Among these techniques, plant tissue culture stands out due to its high propagation rate, the ability to produce disease-free plant material, and the provision of genetic uniformity. Orchids are among the first ornamental plants to be propagated via tissue culture, with the genus Phalaenopsis drawing particular attention for its aesthetic appeal and high commercial potential. This study aimed to develop an effective in vitro micropropagation protocol using flower stalk explants of Phalaenopsis orchids. Three different culture media—1/2 MS, full-strength MS, and Orchimax—were tested in combination with various concentrations of the plant growth regulators BAP and NAA. According to the findings, the combination of 2 mg/L BAP and 1.5 mg/L NAA in ½ MS medium yielded the highest number of shoots, with 18.50±2.29 shoots per plantlet. The same treatment also resulted in the greatest shoot length, at 3.47±0.58 cm. Regarding leaf development, the best result was obtained with 1 mg/L BAP + 0.5 mg/L NAA in full-strength MS medium, producing 4.50±0.50 leaves per plantlet. During the rooting phase, the 1/2 MS medium was used consistently, while varying concentrations of NAA, IBA, and IAA were applied. The highest number of roots (3.00±0.50 per plantlet) was observed with 1.0 mg/L NAA. In terms of root length, the control group produced the longest roots (4.22±0.48 cm), followed by treatments with 2.0 mg/L NAA and 0.5 mg/L IAA. In contrast, high doses of IBA significantly reduced root length. During the acclimatization stage, the plantlets were successfully adapted to pre-greenhouse conditions in a peat and perlite (2:1) mixture, achieving an approximately 90% survival rate. Overall, this study presents a practical, cost-effective, and efficient protocol for the in vitro propagation of Phalaenopsis orchids and contributes to the expansion of tissue culture-based propagation systems within the ornamental plant industry.