Effect of Melaleuca viminalis Essential Oil and Biosynthesized Silver Nanoparticles on Mortality of Sitophilus oryzae

Insects Bio-control specially botanicals have received more attention nowadays. Essential oils are extracted from plants as a natural eco-friendly substance and as an insecticidal property. Moreover, it can be used for synthesis of nano particles pesticides. The current study aimed to use the essential oil of Melaleuca viminalis leaves as pesticides, synthesis of silver nano particles and verify their effectiveness on mortality of rice weevil under laboratory conditions.

The essential oil extracted from leaves of M. viminalis was used at concentrations (10, 20, 30 μL L^-1 air) and silver nanoparticles (2000, 4000, 6000 mg L^-1) at three exposure periods (24, 48, 72 hours) to assess performance against rice weevil larvae and adults.

The mortality rate of adults and larvae increased with increasing concentrations of both insecticides. For larvae after 72 hours was reached to 100% and 93.3% at 6000 mg L^-1 and 30 μL L^-1 air for silver nanoparticles and Melaleuca oil, respectively. Adults mortality after 72 hours, was 100% and 90% at 6000 mg L^-1 and 20 μL L^-1 air for silver nanoparticles and Melaleuca oil, respectively. It was demonstrated from the results that the treatment of silver nanoparticles with low concentration was more effective in mortality rate than Melaleuca oil. Therefore, it can be concluded that the use of nanotechnology for pest control is more economical due to lower lethal doses.