*3.3. Effects of Antibiotic Exposure on AREB in Pakchoi*

The CFUs of TCEB and AREB in plant tissues under different antibiotic treatment conditions were determined, and the rates of AREB to TCEB were calculated, as shown in Figure 3. Compared with the controls, the cultivable AREB levels in TC-, CPL-, and SMX-treated samples reached 0.61–0.85 × 103, 4.63–5.36 × 103, and 4.89–5.18 × 103 CFU·g−1, respectively, which were higher than those in the control samples (0.23 × 103, 3.77 × 103, and 1.26 × 103 CFU·g<sup>−</sup>1). These changes in AREB abundance resulted in dramatic increases in the ratios of AREB to TCEB from 0.23%, 3.77%, and 1.26% of TC, CPL, and SMX resistance, respectively, in the controls, to 0.79–1.23% (Figure 3A), 6.41–8.29% (Figure 3B), and 6.00–7.43% (Figure 3C), respectively, in the corresponding antibiotic-treated plants.
