Figure 4.
Plants grown in Resilience soil show normal ETI responses, and P. syringae effector production is not affected by silicon. (a) Half‐leaves of Arabidopsis ecotype Col‐0 were infiltrated with 5 × 107 CFU/ml of P. syringae pv. tomato DC3000 expressing empty vector (Pto DC3000 (Ev)) or HopZ1a with a C‐terminal HA tag under the control of its endogenous promoter (Pto DC3000 (hopZ1a)). Photographs were taken 22 hrs after infiltration. The HR is indicated with an asterisk. The number of leaves showing an HR is shown below each treatment. Scale bar = 1 cm. (b) Immunoblot analysis of HopZ1a‐HA protein expression in P. syringae pv. tomato DC3000 (Pto DC3000). Pto DC3000 carrying an empty vector (Ev) or HA‐tagged HopZ1a (42.1 kDa) was grown in minimal media to induce the type III secretion system. Equal amounts of proteins were separated on 12% SDS‐PAGE gels, blotted onto nitrocellulose, and probed with HA antibodies. The Ponceau red‐stained blot was used as the loading control. (c) Immunoblot analysis of HopZ1a‐HA protein expression in P. syringae pv. tomato DC3000 (Pto DC3000) as in part b. Pto DC3000 carrying HA‐tagged HopZ1a was grown in minimal media, with different concentrations of potassium silicate pH 5.7 as indicated