Detection of Reactive Oxygen Species in Plant Root Immunity

Reactive oxygen species (ROS) production is a key early defense mechanism in plants when exposed to biotic stress. Upon recognition of conserved microbe-associated molecular patterns (MAMPs) from pathogens by plant receptors, nicotinamide adenine dinucleotide phosphate (NADPH) oxidases in the plasma membrane are activated to produce hydrogen peroxide (H₂O₂). This, in turn, regulates multiple signaling pathways to trigger immunity and suppress pathogen infection. Monitoring the ROS burst in plant leaves can be done within minutes of MAMPs treatment. However, there is limited research on the quantification of ROS production in plant root tissues during the activation of plant immunity. In this study, we introduce a rapid, accessible, and straightforward technique for measuring MAMPs-triggered ROS bursts in the roots of the model legume Medicago truncatula. This method will facilitate the investigation of plant root responses to biotic and abiotic stresses.