Evaluation of influence of different strains of Agrobacterium rhizogenes on efficiency of hairy root induction in Rauwolfia serpentina

Abstract

An improved protocol was established for hairy root induction in Rauwolfia serpentina using two strains of Agrobacterium rhizogenes MTCC 532 and 2364. Hairy root induction efficiency was standardized based on infection time, co-cultivation period, OD600 and acetosyringone concentration. Higher transformation efficiency was established using MTCC 532 (31%) and MTCC 2364 (24%) with 30 min infection time, 72 h co-cultivation period and 0.6 OD600. Transformation efficiency was further enhanced to 55 % with 125 μM acetosyringone. MTCC 532 was proven a better strain over the MTCC 2364 in all the tested factors. Putative transgenic hairy roots were confirmed by polymerase chain reaction using rolA specific primers. Biomass of randomly selected 5 hairy root lines was also significantly enhanced. No significant difference of growth was recorded among the lines except line no 4. In the present study, an enhanced system for Agrobacterium rhizogenesmediated hairy root culture was established which offer an effective means to attain improved transformation efficiency and ultimately beneficial for the industrial scale in vitro production of the secondary metabolite.