Quantitative Detection of Oxidative Burst upon Activation of Plant Receptor Kinases

The oxidative burst or the production of reactive oxygen species (ROS) is a typical cellular response of both plants and animals to diverse abiotic and biotic stresses. Mainly, the (re-)active oxygen species include the superoxide anion (O₂^-), hydrogen peroxide (H₂O₂), and the hydroxyl radical (OH•). Here, we outline the detection of extracellularly produced ROS in plant leaf pieces using a chemiluminescence-based bioassay with the luminol L-012 as a substrate being oxidized in the presence of ROS. Since this type of assay is in use in many laboratories, e.g., as a readout for activation of plant receptor kinases, we include a discussion on the interpretation of results and points addressing problems with the buffers at suboptimal pH values that negatively influence the chemiluminescence production.