Developments of nanoparticle-mediated dsRNA delivery systems to control ToCV and TYLCV infections in plants

Tomato chlorosis virus (ToCV) and tomato yellow leaf curl virus (TYLCV) are two important plant viruses. Co-infection of them leads to exacerbated disease symptoms and poses a significant challenge for control. Using nanomaterials to package and deliver double-stranded RNA (dsRNA) for inducing RNA interference (RNAi) has emerged as a promising antiviral strategy in agriculture.

In this study, two established nanomaterials, chitosan quaternary ammonium salt (CQAS) and aminated mesoporous silica nanoparticles (MSN@NH₂), were selected to package dsRNAs targeting the TYLCV C1 gene, the ToCV RNA-dependent RNA polymerase (RdRP) gene, or the ToCV 1a polyprotein gene, forming CQAS/dsRNA and MSN@NH₂/dsRNA nanoparticles, respectively. The results indicated that these nanoparticles enhance the stabilities of dsRNAs. The efficacy of these nanoparticles against ToCV and TYLCV infection was assessed in tobacco cv. K326, Nicotiana benthamiana, and tomato cv. Micro-Tom plants. The results showed that these nanoparticles could significantly reduce viral gene transcription levels, with inhibition rates ranging from 33.5% to 99.5% depending on the nanoparticle formulation, target virus, and host plant. For instance, in N. benthamiana under co-infection, MSN@NH2/dsRNA nanoparticles inhibited TYLCV and ToCV by 99.5% and 79.8%, respectively. These findings demonstrate that both CQAS/dsRNA and MSN@NH2/dsRNA nanoparticles are effective in controlling ToCV and TYLCV single or co-infection in plants.

Both CQAS and MSN@NH₂ effectively package and protect dsRNA from degradation. Our findings further support the notion that the nanoparticle-mediated RNAi is a promising strategy for virus disease management. This approach contributes to global efforts toward sustainable agriculture. © 2026 Society of Chemical Industry.