Insecticidal activity on Tribolium castaneum and Phenacoccus solenopsis and characterization of active phytonanoparticles.

Phytonanoparticles can be used as an alternative method for pest control in agriculture. The objective of this study was to evaluate the insecticidal activity of mono, bi and trimetallic phytonanoparticles (PNPs) synthesized from cachanilla (Pluchea sericea Nutt. Coville) and epazote (Chenopodium ambrosioides L.) against the red flour beetle (Tribolium castaneum) and the cotton mealybug (Phenacoccus solenopsis). Overall, T. castaneum showed greater sensitivity to PNPs than P. solenopsis. The trimetallic PNPs, Zn/Cu/Mn of P. sericea showed significantly higher effect against T. castaneum than the crude aqueous extract of P. sericea. No other PNPs showed more effect than their respective aqueous plant extract. Physicochemical characterization of the most active PNPs showed that the Zn/Cu/Mn NP of P. sericea had a strong zeta potential of +200 mV, hydrodynamic size of 16 nm, and contains zinc (6.73%), copper (0.13%), and manganese (4.69%). This study suggests that the trimetallic Zn/Cu/Mn PNPs of P. sericea have high insecticidal effect on T. castaneum , but low toxicity on P. solenopsis. Additional research on the mode of action of PNPs on insect targets is required. • Biosynthesis of trimetallic Zn/Cu/Mn green nanoparticles, insecticidal effect on Tribolium castaneum and Phenacoccus solenopsis. [ABSTRACT FROM AUTHOR]