SAG and infection: Here, we showed that the T3E XopB is involved in modulation of SA/ SAG levels and of SA-dependent genes such as PR1 and PR3. This was seen in the interaction between A. thaliana and Pst as well as between C. annuum and Xcv. Thus, infection of susceptible pepper plants with an Xcv xopB deletion strain caused a higher accumulation of SA/SAG and SA-dependent PR transcripts compared to infection with an Xcv wild type strain.