Simple Protocol for Micropropagation and in Vitro Conservation of Plumbago zeylanica L: An Important Indigenous Medicinal Plant

Abstract

A simple protocol was developed for in vitro clonal propagation by multiple shoot induction of Plumbago zeylanica L., a plant having high medicinal values. Root of P. zeylanica is widely used as a traditional medicine. The plant is very popular to different pharmaceutical industry and is mainly harvested from the natural habits. Population growth, urbanization and the unrestricted collection of these plants from the wild population is resulting in an over-exploitation of natural habits. To cope up this alarming situation and to ensure its sustainability, plant tissue culture technique was applied. Micropropagation methodology is a potent alternative approach which has opened extensive areas of research for biodiversity conservation. High frequencies of multiple shoot regeneration (10 to 12 shoots explant-1) were achieved from P. zeylanica from nodal explant on to MS medium fortified with 2.0 mg l-1 BAP and 0.2 mg l-1 NAA. MS medium along with 1.0 mg l-1 BAP and 0.2 mg l-1 GA₃ showed the highest shoot elongation. The elongated shoots were subcultured for rooting on MS medium supplemented with 1.0 mg l-1 IBA. The survival rate of 95% in vitro raised plantlets were acclimatized in poly greenhouse and successfully transplanted to natural condition. In vitro conservation was also evaluated by supplementing various osmotic agents. For in vitro mid-term conservation, the complete plantlets were maintained healthy condition upto 10 months at 10⁰C without any subculture by using MS medium in combination with 2% manitol and 2% sorbitol. All regenerated plants are cytologically stable (2n=24), their chromosomal status same as source plant.