Fig. 1

Three methods of R. rhizogenes-mediated transgenic hairy roots development for cucumber. a Procedure of solid-medium-based hypocotyl-cutting infection (SHI) method. Sterilized seeds were sowed on MS solid medium and then cut hypocotyl off for K599 infection. The sterilized filter paper was used to keep the humidity of the infected sites. b Procedure of rockwool-based hypocotyl-cutting infection (RHI) method. Sterilized seeds were sowed into sterilized rock wool and then cut the seedlings hypocotyl off for infection using the K599 solution. c Procedure of peat-based cotyledon-node injection (PCI) method. Sterilized seeds were sowed into sterilized peat substrate and the K599 mass collected from screening medium was injected into the cotyledon-node for inducing transgenic hairy roots