Hairy Root Induction in Burdock (Arctium lappa L.)

Abstract

Background: Arctium lappa is a medicinal plant, which natively grows in Iran. Arctiin and arctigenin are two of the most important secondary metabolites produced in this plant and used as anticancer reagents. Application of biotechnological methods for increasing the production of these metabolites is very essential. Recently, induction of hairy roots in plants to improve the production of desirable secondary metabolites has been considered. Objective: In this study, hairy roots were induced in Arctium lappa using Agrobacterium rhizogenes, strain AR15834. Methods: The leaf explants and seedlings of Burdock were used for the hairy roots induction. The leaf explants were turned brown and died when cultured in vitro. To improve the viability of these explants, different antioxidants including ascorbic acid (ASC), citric acid (CIT), polyvinylpyrrolidone (PVP) and L-cysteine were added to the MS medium, in different concentrations either alone or in combination with each other. Polymerase Chain Reaction (PCR) for rolB gene confirmed the morphological identification of the transformed hairy roots. Results: Although the best antioxidant reagent was PVP 0.5% (w/v), it did not stop tissues browning of the leaf explants when they were co-cultured with A. rhizogenes for the hairy roots induction. When the two or three weeks old seedling were used for the hairy roots induction, the roots were observed 2 weeks after the bacterial infection with 5% frequency. Conclusion: In this study, A. rhizogenes induced hairy roots in Burdock. To the best of our knowledge, this is a first report on the hairy roots induction in Arctium lappa.

Keywords

• arctium lappa l
• burdock
• agrobactrium rhizogenes and hairy roots