Electrophysiological signatures decode herbivore-specific defense dynamics and elicitor-induced immune activation in rice.

Herbivore infestation triggers complex defense mechanisms in rice, primarily regulated by phytohormones. However, the traditional approach of analyzing plant hormone profiles as an indicator of plant responses to herbivore stress suffers from time-consuming detection, high costs, and destructive sampling of plant tissues. In this study, we propose and validate a novel approach using plant electrophysiological parameters-capacitance, resistance, impedance, and reactance-as a rapid, non-invasive biomarker of rice responses to two major herbivorous pests: the brown planthopper (Nilaparvata lugens, BPH) and the striped stem borer (Chilo suppressalis, SSB). Systematic modelling revealed herbivore-specific temporal electrophysiological response dynamics, reflecting perturbations in water and nutrient transport, dielectric substance movement, and metabolic energy flux in infested rice plants. Based on these dynamics, we developed predictive models for rice yield potential, drought resistance, and metabolic adaptability under biotic stress. In parallel, we analyzed phytohormone levels and found that changes in electrophysiological traits were strongly associated with jasmonic acid and jasmonic acid-isoleucine accumulation, indicating that these electrical signals capture key aspects of the plant's immune status. Beyond detecting herbivore-induced defenses, electrical patterns were also mirrored in transgenic rice overexpressing planthopper-derived elicitors (e.g. Myosin/PDI1), indicating electrophysiological signatures act as defense activation markers, thus enabling high-throughput screening of herbivore elicitors. Together, our results highlight the potential of plant bioelectrical signals as fast, integrative, and scalable indicators of stress responses, with applications in crop protection and elicitor-assisted resistance breeding.