A. Pst DC3000 (AvrRps4) induced HR lesions are contained in 4-week-old wild-type (Col-0). Representative images of disease symptoms were photographed at 0, 1, 2, 3, 4, 5, 6 and 8 dpi after local infection with avirulent Pst DC3000 (AvrRps4). Region I:At the site of pathogen infection, in the red dashed-line areas. Region II: Regions adjacent to the site of infection, in the yellow dashed-line areas and outside the red dashed-line areas. Region III: Uninfected systemic tissues, outside the yellow dashed-line areas. This experiment was repeated three times with similar results. B. False color images and quantitative analyses of the changes of chlorophyll fluorescence parameters Fv/Fm (Region 1, 2 and 3) induced by avirulent Pst DC3000 (AvrRps4) at 1, 2, 4 and 6 dpi, and the false color code depicted at the bottom of each image ranged from 0.000 (black) to 1.000 (purple). The statistical data of Fv/Fm support the results seen in the images.