Fig. 2: Assessment of Cu tolerance of transgenic apple plants and calli subjected to CuSO4 treatment.

a Phenotypes of three transgenic apple lines overexpressing MdWRKY11 and an untransformed control plant treated with 500μM CuSO4 for 10, 20, and 30 days. b Cu tolerance of transgenic MdWRKY11-overexpressing and MdWRKY11 RNAi calli and control calli cultured on media supplemented with excess Cu (300μM CuSO4) or normal Cu concentrations for 20 days