Thiamethoxam used as nanopesticide for the effective management of Diaphorina citri psyllid: an environmental-friendly formulation

Abstract

Although insecticides are essential for the effective pest management, the development of sustainable formulations remains a challenge in modern agriculture. This work focuses on the encapsulation of thiamethoxam in polymeric micelles, a nanodelivery system. The nanomicelles, prepared by thin-film hydration method, presented 94.5 ± 10.26% of encapsulation efficiency, average size of 85.14 ± 2.23 nm, zeta potential of −5.3 mV, and acceptable homogenous distribution. Water solubility of thiamethoxam nanomicelles showed an increase by 41.7% in relation of thiamethoxam compound. Toxicity assessment was applied to Raphidocelis subcapitata Korshikov and Artemia salina Linnaeus organisms. The EC50 values obtained for microalgae of polymeric nanomicelles > polymeric nanomicelles loaded thiamethoxam > commercial pesticide. EC50 values obtained for Artemia salina in all treatments could not be compared due to lack of sensitivity shown by this organism to the adopted treatments. Nanoformulation effectiveness was evaluated against D. citri caged in citrus plants grown under greenhouse conditions, in comparison to that of standard formulations. Results have suggested that thiamethoxam nanomicelles might be effective in controlling D. citri around dose 2-fold lower than commercial formulations. Highlights Nanomicelles are prepared based on Pluronic ® F127 and Pluronic® P123 Thiamethoxam is effectively encapsulated in micelle nanostructures Thiamethoxam nanoinsecticide is tested against Diaphorina citri Kuwayana