The accumulation level of H2O2 was observed using DAB as described previously (Zhu et al., 2020 (link)). Endogenous H2O2 concentrations were determined according to the protocol described by Chen et al. (2019 (link)) using a hydrogen peroxide assay kit (Solarbio) (Chen et al., 2019 (link)). Qualitative test of O2•− was observed using NBT with a similar procedure to that described previously (Zhu et al., 2020 (link)). The content of O2•− in N. benthamiana leaves was measured according to previously methods as described by Cai et al. (2018 (link)) using a Micro Superoxide Anion Assay Kit (Solarbio) (Cai et al., 2018 (link)).