Title : Improving growth and hyoscyamine synthesis in datura hairy roots using two rhizobacteria strains isolated from the tomato rhizosphere
Abstract:
This study elucidated the effect of inoculation of two bacterial strains of Pseudomonas (Pseudomonas fluorescens T8 and Pseudomonas fluorescens T9) isolated from the rhizosphere of tomato and known as Plant Growth Promoting Rhizobacteria by production of different plant promoter molecules on hairy root growth and production of the tropane alkaloid Hyoscyamine in vitro. The hairy root lines (LDS,L DT,L DI) cultivated on B5 medium were induced by Rol (a,b,c and d) gene transfert from Rhizobacterium rhizogenes (A4 strain ) and have powerful growth rate. The effect of T8 and T9 inoculation in two times of 5 and 10 days on biomass and hyoscyamine content of hairy roots showed that they stimulate the development of hairy root growth when exposed for 10 days to the bacterial inoculation. After drying the tissues at 60°C for 24 h, The results of the root weight showed that Pseudomonas T9 boosted LDS biomass to 0,170 g compared to 148 g for the control and LDT biomass to 0,245 g compared to the control 0,193g with a considerable hyoscyamine levels increased after bacterial inoculation. Chromatographic analysis of tropane alkaloid showed that the best hyoscyamine result of 14,262 mg /g DW was obtained with LDT which represents an improvement of 68% compared to the control. For LDI, an increase of 12% was recorded with strain T8 where the concentration reached 7,825mg/g DW.
