4.2. PLB Induction

The A. roxburghii plantlets were used for the PLB induction. After removing their leaves and roots, the stems were cut into segments with nodes of 0.3–0.5 cm in length. The stem nodes, which served as explants, were added to different PLB induction media (Table 1). For each tested medium, 30 Petri dishes were inoculated with 20 explants for the PLB induction at 25 ± 2 °C with a 16 h light/8 h dark photoperiod (1500–2000 lux irradiation). Fifteen Petri dishes per medium were randomly selected to record the time required for PLB emergence and to calculate the PLB induction rate at 30 dpi. The PLB induction rate (%) was calculated using the following formula: number of explants with PLBs/number of explants used to inoculate the medium × 100.