Figure 7.

Spermine promotes AvrBsT-triggered cell death. A, Cell death phenotypes in N. benthamiana leaves 2 d after infiltration with A. tumefaciens carrying the indicated constructs and supplemented with 10 mm MgCl₂ or 1 mm spermine. Red, orange, and blue circles indicate full, severe, and no cell death, respectively. B, Quantification of cell death levels. Cell death levels were rated based on a 0 to 3 scale: 0, no cell death (less than 10%); 1, weak cell death (10%–30%); 2, partial cell death (30%–80%); and 3, full cell death (80%–100%). C, Electrolyte leakage from leaf discs at different time points after infiltration with A. tumefaciens carrying the indicated constructs and supplemented with 10 mm MgCl₂ or 1 mm spermine. Data are means ± sd from three independent experiments. Different letters indicate statistically significant differences at different time points (Fisher’s lsd; P < 0.05). [See online article for color version of this figure.]