Figure 4.

ROS production and callose deposition increase rapidly following the removal of lesion suppression medium. Plants (the wild type in black circles and aca4/11 in white circles) were grown for 10 d under “suppressing conditions” provided by a 15 mm NH₄NO₃ supplement to the standard hydroponic solution. Plants were then transferred to the standard hydroponic solution for the indicated times before harvest. A, ROS production was monitored by staining with diaminobenzidine (DAB). B, Callose deposition was monitored by staining with aniline blue. C, The area of lesions was calculated from aniline blue-stained leaves. Values and error bars represent means ± se for A and B and median ± 75th percentile for C. n = 8 individual leaves (except for 0 h, for which n = 4).