Nanoparticle-Mediated dsRNA Delivery Used as a Broad-Spectrum Synergistic Nanonucleic Acid Adjuvant to Control Sogatella furcifera

The enhanced detoxification capacity caused by the induction or constitutive overexpression of metabolic enzyme genes has complicated sustainable and efficient pest control strategies. This study clarified the detoxification effects of two P450 genes, CYP4CE3 and CYP6FJ3, on multiple insecticides in Sogatella furcifera. The chimeric double-stranded RNA (ch-dsRNA) of these two genes was obtained by using the L4440-HT1115 (DE3) RNase III- system, and the RNA interference (RNAi) effectiveness of ch-dsRNA was verified by microinjection. MON-NH2 was subsequently used to deliver dsRNA as a synergist (MON-NH2@ch-dsRNA) to effectively protect dsRNA from nuclease degradation and stably inhibit CYP4CE3 and CYP6FJ3 expression through insect sap-feeding. Compared with the single insecticide application, the addition of MON-NH2@ch-dsRNA led to an increase in the mortality rates of imidacloprid, clothianidin, dinotefuran, and sulfoxaflor by 22.22-38.90%, with the synergistic enhancement of nitenpyram, yielding a ratio of 1.90-fold. Moreover, the field experiment results revealed that the control effect of nitenpyram was significantly improved by 14.53 and 10.30% on days 3 and 7, respectively, following the application of MON-NH2@ch-dsRNA. Therefore, MON-NH2@ch-dsRNA can be used as a nucleic acid nanosynergist with a broad-spectrum synergistic effect on insecticides in controlling S. furcifera.