Plant Science Research, Vol. 38, 2016

Rapid in vitro shoot multiplication and analysis of plumbagin in Agrobacterium rhizogenes mediated hairy root culture of Plumbago zeylanica L.

Plumbago zeylanica L. is an important medicinal plant and roots are used for dyspepsia, piles,  diarrhoea, skin diseases, leprosy and rheumatism. A protocol for rapid in vitro-multiplication  through axillary bud proliferation was developed. Approximately 7 shoots were produced from  a single nodal segment of a four year old field grown plant after 4 weeks of culture on  Murashige and Skoog’s (MS) basal medium supplemented with 2 mg/l BAP + 100mg/l adenine  sulphate. Optimum number of roots was induced (~15/shoot) upon transferring the individual  regenerant to half strength MS medium supplemented with 0.5mg/l IBA. Hairy roots were  initiated with the A4 strain of Agrobacterium rhizogenes which exhibited optimum growth in half  strength MS medium containing 4% sucrose. Growth kinetic studies demonstrated a maximum  11 fold increase in root biomass yield after 6 weeks of culture. The fresh hairy roots produced  0.61% higher amounts of plumbagin over the untransformed control roots. The present research  findings revealed for the first time the potentialities of the hairy root cultures of P. zeylanica for  the production of the important secondary metabolite, plumbagin.