Assessment of Salt Stress to Arabidopsis Based on the Detection of Hydrogen Peroxide Released by Leaves Using an...

Salt stress will have a serious inhibitory effect on various metabolic processes of plant cells, this will lead to the excessive accumulation of reactive oxygen species (ROS). Hydrogen peroxide (H₂O₂) is a type of ROS that can severely damage plant cells in large amounts. Existing methods for assessing the content of H₂O₂ released from leaves under salt stress will cause irreversible damage to plant leaves and are unable to detect H₂O₂ production in real time. In this study, on the strength of a series of physiological indicators to verify the occurrence of salt stress, an electrochemical sensor for the detection of H₂O₂ released from leaves under salt stress was constructed. The sensor was prepared by using multi-walled carbon nanotube-titanium carbide-palladium (MWCNT-Ti₃C₂T_x-Pd) nanocomposite as substrate material and showed a linear response to H₂O₂ detection in the range 0.05-18 mM with a detection limit of 3.83 μM. Moreover, we measured the determination of H₂O₂ released from Arabidopsis leaves at different times of salt stress by the sensor, which was consistent with conventional method. This study demonstrates that electrochemical sensing is a desirable technology for the dynamic determination of H₂O₂ released by leaves and the assessment of salt stress to plants.