CeO2 nanohybrid as a synergist for insecticide resistance management

• MON@CeO 2 has superoxide dismutase mimicking activity to scavenge ROS. • MON@CeO 2 restrained insecticide resistance of Nilaparvata lugens. • MON@CeO 2 inhibited the gene expression of ROS-dependent detoxifying enzyme CYP450. • MON@CeO 2 is a broad-spectrum nanosynergist against insecticide resistance. Agricultural applications of nanomaterials, such as nanofertilizers, nanopreservation technologies, nanopesticides, and plant nanosensors, have recently attracted much attention. Herein, the CeO 2 -based nanohybrid MON@CeO 2 was designed as a reactive oxygen species (ROS) inhibitor to effectively improve the susceptibility of insect pests to insecticides. MON@CeO 2 was fabricated by intercalating CeO 2 into mesoporous organosilica nanoparticles (MONs). The obtained MON@CeO 2 showed a regular spherical shape with an average particle size of 45.4 nm, good monodispersity, and a negative surface charge (-14.6 mV). Bioassay results showed that MON@CeO 2 significantly enhanced the toxicity (more than 2-fold) of nitenpyram, sulfoxaflor, and clothianidin against laboratory insecticide-resistant and field strains of Nilaparvata lugens . In particular, MON@CeO 2 orchestrated host detoxification metabolism via downregulating ROS-dependent P450 gene expression, thus reducing host detoxification enzyme activities to overcome insecticide resistance. Furthermore, MON@CeO 2 restrained host insecticide resistance in the notorious agricultural pests Aphis gossypii , Spodoptera frugiperda , and Sogatella furcifera . Therefore, MON@CeO 2 could be used as a broad-spectrum nanosynergist against insecticide resistance, which would be a novel strategy for sustainable pest management.