Micropropagation of Gotu Kola (Centella asiatica L.) via Runner Tip Culture

Gotu kola (Centella asiatica L.) is one of the most valuable medicinal plants. Due to the reduction of surface water and the limitation of dispersion, the natural populations of this plant species are in extinction risk. The purpose of this experiment was to introduce a tissue culture protocol for rapid micropropagation of the Gotu kola plant. For callus induction, explants were established on Murashige and Skoog (MS) medium supplemented with different concentration of 6-benzylamino purine (BA) at six levels (0, 1, 2, 3, 4, and 5 mgL-1) and α-naphthaleneacetic acid (NAA) at four levels (0, 0.25, 0.5, and 1 mgL-1). The best callogenesis was obtained with maximum callus induction (83.33%), fresh weight (4.26 g), and daily growth rate (0.14 g/day) by combined application of 4 mg L-1 BA and 1 mg L-1 NAA. Different concentrations of BA (0, 1, 2, 3, 4 and 5 mgL-1) and NAA (0.1 mg L-1) were used for shoot regeneration. Combination of BA (4.0 mgL-1) with NAA (1.0 mgL-1) showed the highest shoot proliferation (74.99%), maximum number of shoots (7.66), petiole (6.66) and the longest shoots (1.56 cm). The effects of, IBA (0, 0.5, 1, 1.5, 2, 2.5 mgL-1) were examined on adventitious root formation. MS medium supplemented with IBA (1 mgL-1) showed the best percentage of rooting (84.66%), maximum number of roots Per plantlet (65), and the longest roots (3.33 cm) along with the highest percentage of survival (74.99%).