Figure 3.

Quantification of endophytic bacterial strains in tomato plants. Bacterial re-isolation was carried out from seed-inoculated whole plants at the end of the acquisition period (Day 11) and from shoots or roots of plants at the end of the mirid-mediated transmission (Day 14) with Macrolophus pygmaeus (A) or Nesidiocoris tenuis (B). The quantity of re-isolated bacteria are expressed as colony forming units (CFU) per gram of fresh weight of the whole plant (CFU g⁻¹) and plant shoot (CFU g⁻¹), or as CFU for each plant root (CFU root⁻¹) of mock-inoculated plants (Mock, green) and plants inoculated with Paraburkholderia phytofirmans PsJN (PsJN, red) or Enterobacter sp. 32A (32A, blue). The two-way analysis of variance showed no significant differences between the two experimental repetitions (p > 0.05) and data from the two experiments were pooled. Mean and standard error values for positive samples and at least nine replicates (plants) are presented for each treatment. For each treatment, no significant differences were found in the pairwise comparisons between PsJN- and 32A-inoculated samples, according to the Mann–Whitney test (p ≤ 0.05). Neither PsJN nor 32A bacterial colonies were isolated from the mock-inoculated samples.