Micropropagation of Philodendron ‘White Knight’ Through Adventitious Shoot Regeneration

Philodendron ‘White Knight’ is a popular climbing evergreen plant typically propagated through stem cuttings. However, this method is slow and inefficient, making it challenging to meet the rising market demand. In vitro culture could enhance the multiplication rate of this cultivar. However, research on its in vitro propagation is limited. Therefore, the objectives of the present study were to investigate the impact of silver nanoparticles (Ag NPs) on the surface sterilization of Philodendron ‘White Knight’ petioles, to study the influence of plant growth regulators on adventitious shoot regeneration, shoot multiplication, and root induction. Aseptic petiole explants (100%) were obtained after treatment with 40 mg L-1 Ag NPs for 60 minutes. The highest rate of adventitious shoot induction (52.6%) and the maximum shoot number (13.9 shoots per petiole) were achieved on Murashige and Skoog shoot multiplication B (MS-B) medium with 20 µM of 2-isopentenyl adenine (2-IP) and 5.0 µM of naphthalene acetic acid (NAA). The highest number of shoots (34 shoots per shoot tip) with a length of 5.1 cm was obtained on MS-B medium with 5.0 µM 2-IP and 2.5 µM NAA. The highest root induction (100%), the maximum root number (8.2 roots per shoot), and the greatest plantlet height (9.1 cm) were achieved on half-strength Murashige and Skoog medium containing indole-3-butyric acid (10.0 μM). The rooted plantlets of Philodendron ‘White Knight’ were transplanted in a transplanted into a substrate composed of 10% peat moss, 50% orchid stone, and 40% coconut husk chips, and acclimatized in a greenhouse environment, achieving a survival rate of 100%. This micropropagation protocol can be used for the commercial propagation of Philodendron ‘White Knight’ and related species.