Fig. 2.

Detection of the pathogen in leaf tissues in Pi-colonized/−uncolonized Oncidium. a E. chrysenthemi (Ec) was locally inoculated on the second leaf of Pi-colonized/−uncolonized cuttings, respectively. Local and distal leaves were collected separately. b Ec DNA levels in leaves were detected by qPCR of 16S rDNA 1, 2 and 3 days after infection, Pi DNA in leaves and roots were detected with EF-hand DNA primer pair 10 days after inoculation, data represent the means ± SE of 3 replicates and were normalized to the plant ACTIN DNA level, values with the same letter were not significantly different (p < 0.05). c Levels of endogenous salicylic acid, jasmonic acid, ethylene and H₂O₂ 24 h after infection of the leaf with Ec. Data represent the means ± SE of 3 replicates, values with the same letter were not significantly different (p < 0.05). PI: qPCR for Pi and Ec DNA in roots/leaves of Pi-colonized cuttings. CK: uncolonized plants. EC1d, EC2d and EC3d indicates the detection of the presence Pi and Ec in Pi-colonized/−uncolonized plants 1, 2, or 3 days after Ec infection, relative values normalized to the plant ACTIN DNA level. CK: control plant. P: Pi-colonized plants; (P)EL: local infected leaf of Pi-uncolonized (EL) or -colonized (PEL) plants inoculated with Ec. (P)ED: distal leaves of Pi-uncolonized (ED) or –colonized (PED) plants inoculated with Ec