Optimization of hairy root induction in chicory (Cichorium intybus L.) and effects of nanoparticles on secondary metabolites accumulation

Hairy root culture is an effective method to produce secondary metabolites. In fact, hairy roots are genetically and biologically stable and also they are able to produce metabolites without hormones. Chicory (Cichorium intybus L.) is one of the most important medicinal plants with valuable medicinal compounds. In this research, hairy roots were induced by different Agrobacterium rhizogenes strains using leaf and petiole explants. In the second experiment, the effect of Iron and zinc oxide nanoparticles was studied on hairy roots biomass accumulation and secondary metabolites production. The results of experiments showed that the highest hairy root induction (60 percent), were observed in the A4 strain and leaf explants. Also the iron oxide nanoparticles. and ATCC15834 strain were superior for highest fresh (4.53 g) and dry weight (0.4 g) productivity, growth index (24.41) and total phenolic content (4.65 mg g-1 DW) in hairy roots. Overall, the strain and explant types had considerable effects on the hairy roots induction and iron oxide nanoparticles and ATCC15834 strain were more effective in roots growth and secondary metabolites production.