Figure 6

SAR Induction in Atelp3-10 Plants. (A) Expression of six SAR-associated genes in systemic leaves of WT, npr1, Atelp3-10, and Com(C) plants. Com(C), 35S::AtELP3 Atelp3-10 transgenic plants. Three lower leaves on each plant were inoculated with Psm ES4326 (OD₆₀₀ = 0.002) (+SAR) or mock-treated with 10 mM MgCl₂ (−SAR). Two days later, total RNA was extracted from the upper uninfected/untreated leaves and analyzed for the expression of indicated genes by real-time qPCR. Expression was normalized against constitutively expressed UBQ5. Data represent the mean of three independent samples with SD. Different letters above the bars indicate significant differences (p < 0.05, Student’s t-test). Note that the comparison was made among WT, npr1, Atelp3-10, and Com(C) for each gene/treatment. (B) SAR induction in WT, npr1, Atelp3-10, and Com(C) plants. Three lower leaves on each plant were inoculated with Psm ES4326 (OD₆₀₀ = 0.002) (+SAR) or mock-treated with 10 mM MgCl₂ (−SAR). Two days later, two upper uninfected/untreated leaves were challenge-inoculated with Psm ES4326 (OD₆₀₀ = 0.001). The in planta bacterial titers were determined immediately and three days after challenge inoculation. Cfu, colony-forming units. Data represent the mean of ten independent samples with SD. Psm ES4326 grew significantly less in the SAR-induced WT, Atelp3-10, and Com(C) plants than in the mock-treated plants (*All p < 0.05, Student’s t-test).