Establishment of Hairy Root System Mediated by Ri Plasmid and its Advances in Biosynthesis of Plant Secondary Metabolites

The hairy roots of plants can be induced by the root inducing plasmid (Ri) of Agrobacterium rhizogenes. With high growth rate and genetic stability, the hairy root system can be used in the biosynthesis of secondary metabolites as wild-type roots. The in vitro hairy root culture system provides a new process with active medicinal plant ingredients in the industrial fermentation of commercial-scale bioreactor technology. This paper summarizes the genetic transformation mechanism of hairy roots induced by the Ri plasmid of Agrobacterium rhizogenes, and the current research on secondary metabolites of hairy roots and directions of future research, thereby offering a new perspective on the study of secondary metabolites of hairy roots at the level of gene expression.