In vitro propagation of Dillenia pentagyna Roxb.: a medicinal tree with high conservation priority
摘要
The current investigation describes the first successful report on the in vitro propagation of Dillenia pentagyna Roxb., using nodal explants obtained from a mature tree. Of the four cytokinins evaluated at various concentrations, the MS medium containing 0.5 mg L−1 BAP was optimal for inducing shoots from nodal explants. A monthly subculture of mother explants on the same medium composition significantly influenced shoot multiplication, and a maximum of 8–10 shoots with a mean shoot number of 8.09 ± 0.21 were regenerated after the third subculture on MS medium containing 0.5 mg L−1 BAP. In another approach, shoots were also multiplied by separating shoot clumps along with the mother tissues, excising apical shoots, and performing repeated subcultures for different passages. Rooting in shoots was quite difficult, and in vitro rooting was obtained only in those mature shoots that were intact with the mother tissue (blackish or brownish) at the basal portion or root-shoot junction. Optimum rooting was observed on MS medium containing 2.0 mg L−1 IBA, with a 66.6% rooting rate. About 80% of the plants survived after acclimatization. The developed in vitro propagation system could serve as a foundation for the biotechnological advancement of D. pentagyna, especially in conservation and production of bioactive compounds.