Novel application of biodegradable chitosan in agriculture: Using green nanopesticides to control Solenopsis invicta

Botanical pesticides are biological pesticides that are environment friendly. However, their instability and short persistence limit their application. In this study, pH sensitive chitosan based rotenone (Rot) nanoparticles (CS/CMCS/Rot-NPs) were prepared using chitosan and carboxymethyl chitosan to take advantage of the acidic nature of the red fire ant midgut. Chitosan based nanoparticles showed photoprotective and slow sustained release effects on Rot and significantly increased the insecticidal activity of Rot against red fire ants. The 24–96hLC50 of CS/CMCS/Rot-NPs against red fire ants was 3.28–6.84 fold that of Rot. The CS/CMCS/Rot-NPs significantly reduced the venom alkaloid content of red fire ants and their living environment and weakened their survival by increasing their survival cost in the ecological environment. Nanotechnology combined with botanical pesticides can be used as a novel, safe, effective, and ecofriendly method to control red fire ants. [Display omitted] •Innovative use of nanopesticides to control Solenopsis invicta•Nanoparticles enhanced the insecticidal activity of rotenone against red fire ants.•Effective weaken the attack ability of red fire ants.•Capable to increase the survival cost of red fire ants•A safe, effective, and eco-friendly method for the control of red fire ants