FIGURE 2.

Pathogenicity and spreading ability analysis of the pathogenic strain M228 and its mutants M228ΔT6SS. (A) Pathogenicity analysis. The pathogenicity of the mutant M228ΔT6SS mutant was reduced by 69.65% compared with that of the wild-type strain. The lesion length is the average of five replicates. Statistical significance was determined by Student’s t-test. “**” Means the difference is significant at the 0.01 level. (B) Spreading ability analysis+. The spreading ability of mutant M228ΔT6SS in leaf veins was significantly different from that of wild-type M228. The spreading range of M228 in leaf veins increased with an increase in incubation time, and fluorescence began to weaken after 12 days. However, the spreading ability of M228ΔT6SS in leaf veins was significantly weakened, and it failed to expand rapidly in leaf veins, and only showed weak fluorescence near the inoculation point.