CeO2 nanohybrid as a synergist for insecticide resistance management

Agricultural applications of nanomaterials, such as nanofertilizers, nanopreservation technologies, nanopesticides, and plant nanosensors, have recently attracted much attention. Herein, the CeO2-based nanohybrid MON@CeO2 was designed as a reactive oxygen species (ROS) inhibitor to effectively improve the susceptibility of insect pests to insecticides. MON@CeO2 was fabricated by intercalating CeO2 into mesoporous organosilica nanoparticles (MONs). The obtained MON@CeO2 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@CeO2 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@CeO2 orchestrated host detoxification metabolism via downregulating ROS-dependent P450 gene expression, thus reducing host detoxification enzyme activities to overcome insecticide resistance. Furthermore, MON@CeO2 restrained host insecticide resistance in the notorious agricultural pests Aphis gossypii, Spodoptera frugiperda, and Sogatena furcifera. Therefore, MON@CeO2 could be used as a broad-spectrum nanosynergist against insecticide resistance, which would be a novel strategy for sustainable pest management.

Automated summary

The CeO2-based nanohybrid MON@CeO2 can effectively enhance the susceptibility of insect pests to insecticides, reduce insecticide resistance by regulating host detoxification metabolism, and have broad-spectrum applications.