In vitro regeneration of Melastoma malabatricum Linn. through organogenesis and assessment of clonal and biochemical fidelity using RAPD and HPLC

Abstract

Melastoma malabatricum Linn. is an important medicinal plant used in folk medicine for the treatment of various infectious diseases. We developed an in vitro protocol for direct adventitious shoot regeneration from leaf explants of M. malabatricum. Murashige and Skoog (MS) was the most efficient basal medium for shoot regeneration. Multiple adventitious shoot formation was higher in medium supplemented with 3 % sucrose than maltose or fructose. Leaf explants cultured on MS medium supplemented with α-naphthaleneacetic acid (NAA) and thidiazuron (TDZ) showed the highest shoot regeneration (78.00 ± 0.58 %) and the largest number of shoots per explant (11.67 ± 3.05). MS supplemented with gibberellic acid (GA3) was the most effective for shoot elongation. The highest number of roots per explant (10.67 ± 3.51) occurred on MS supplemented with indole-3-butyric acid (IBA), indicating the IBA was more effective to induce rooting than indole acetic acid. Explants with intact petioles and lamina were more responsive and produced a larger number of shoots per explant (14.67 ± 2.52) than explants with lamina alone (8.00 ± 2.00). Histology and scanning electron microscopy of regenerated shoots confirmed the occurrence of direct organogenesis. Random amplified polymorphic DNA analysis confirmed that in vitro regenerated plants were genetically similar to their mother plant. High-performance liquid chromatography of phenolic acids in leaf extracts of regenerants revealed no significant differences in the phenolic compound profile compared with mother plants. Our in vitro regeneration protocol represents a valuable tool for germplasm conservation and genetic transformation of M. malabatricum.