Sulfur nanocomposites with insecticidal effect for the control of Bactericera cockerelli (Sulc) (Hemiptera: Triozidae)

The purpose of this research was to synthesize nanocomposites formed by sulfur nanoparticles, coated with eucalyptus and rosemary essential oil. To determinate the insecticidal effect in the control of nymphs of paratrioza ( Bactericera cockerelli Sulc) in potato crops. A solution of thiosulfate was reduced to zero valent sulfur, the sulfur nanoparticles were coated with eucalyptus and rosemary essential oil at three concentrations: 0.25%, 0.5% and 0.75%. The samples were characterized by UV-visible spectroscopy, energy dispersive spectroscopy, transmission electron microscopy and scanning electron microscopy. Insecticidal efficacy was evaluated at 24, 48 and 72 hours after application. Furthermore, efficacy was compared versus the commercial insecticide thiamethoxam 0.25% and a control. The results show that eucalyptus nanocomposites at concentrations: 0.25%, 0.5% and 0.75% and rosemary nanocomposites at concentration of 0.5%, have an insecticidal efficacy of 100% for the control of insect nymphs 24 hours after application. While the insecticidal efficacy of rosemary nanocomposites at concentrations of 0.25% and 0.75% increases over time, reaching 100% at 24 and 72 hours respectively. The synthesized nanocomposites are more effective in controlling nymphs of paratrioza than the commercial insecticide thiamethoxam. Could be used for the development of new insecticides.