Figure 1.

Deletion of hrcC or hrpE causes different in planta bacterial growth phenotypes of Xanthomonas campestris pv. campestris (Xcc) B94, B186 and B305. (A) Xcc population sizes within Arabidopsis leaves 4 days after hydathode inoculation (inoculation by spraying bacteria onto rosette leaves of guttating plants). Bars are means ± standard error. *Significant difference from the wild‐type version of the same strain on the same host genotype (t‐test, P < 0.05). WT, wild‐type strain; ΔhrcC, isogenic strain with unmarked deletion of hrcC gene. This and all other experiments in all figures were repeated with similar results on at least two separate dates unless specifically noted. (B, C) Xcc leaf populations 3 days after inoculation of Arabidopsis by vacuum infiltration. (D) In planta growth curve of B305 ΔhrcC/hrpE and wild‐type B305 after inoculation by vacuum infiltration into Arabidopsis Col‐0 leaves (dpi, days post‐inoculation). (A–D) Mean ± standard error of mean; bar fill in (A), (B) and (C) indicates plant genotype. cfu, colony‐forming units. (E) Representative leaf disease symptoms 7 days after vacuum infiltration. Xcc strain genotype noted below and to the left of the photographs.