Scheme 1.

Schematic representation of the induction of mechanical injury in Arabidopsis leaves. The polyunsaturated fatty acids within the plasma and chloroplast membranes are shown to be oxidized in reactions subsequently leading to the formation of reactive oxygen species (O₂ ^•− and ¹O₂) and LOOH. The lower panel shows a comprehensive summary of reaction mechanism leading to expression of defense response genes and details on usage of fluorescent probes utilized in confocal laser scanning microscopy.