In vitro propagation, SEM analysis, and genetic fidelity assessment using SCoT markers in Decalepis salicifolia, an endangered medicinal plant

Decalepis salicifolia (Bedd. ex Hook.f.) Venter is an important medicinal plant endemic to south Western Ghats of India. The immense pharmacological properties of the plant is due to presence of number of biologically active compound especially 2‑hydroxy-4-methoxybenzaldehyde (2H4MB) which is a vanillin isomer. 2H4MB is used in the preparation of various bakery products. Due to the multiple uses of the plant, its commercial demand has increased significantly which has led to its over-exploitation. Because of over-exploitation, the natural population of D. salicifolia is rapidly disappearing, and is listed as critically endangered plant by IUCN. Therefore to meet the demand of the plant for commercial purposes as well as ensure the natural population is conserved, the in vitro propagation approach provides an efficient alternative. In the present study, maximum in vitro shoot proliferation was obtained by culturing the shoot tip on Murashige and Skoog's (MS) medium supplemented with a combination of 5 μM benzyladenine, 1.0 μM indole butyric acid, and 20.0 μM adenine sulphate. Microshoots were rooted effectively on half strength MS medium augmented with 2.5 μM indole-3-butyric acid. Various physiological parameters along with scanning electron microscopic analysis of leaves confirmed the successful adaptation of the plantlets to the natural environmental condition. Presence of 2H4MB in vitro raised plant was confirmed with the help of FTIR. SCoT marker analysis of mother and in vitro regenerated plant produced a high percentage of monomorphic bands hence establishing a clonal fidelity between the both. Thus in vitro propagation protocol developed for D. salicifolia can help us to reduce the exploitation pressure on the natural population of the plant and contributes in the ecorestoration, conservation, and cultivation of the plant.