Spatial distribution of flavonoid glycosides (Table 1) in apple pericarp. The intensities were calculated as the logarithm of the normalized ion trace. MS images have been acquired with a raster step of 150 μm. (A) Optical image. (B) Image reconstructed from XIC at m/z 447.093. This mass can be assigned either to quercetin-rhamnoside or to kaempferol-6S. (C) Image reconstructed from XIC at 435.129 (phloretin-6S). (D) Image reconstructed from XIC at 463.088 (quercetin-6S). (This figure is available in colour at JXB online.)