[G] 英語口頭発表

[G-01] Effect of colloidal silica nanoparticles on survival and fecundity of the two-spotted spider mite, Tetranychus urticae Koch

◯Faten Abdelsalam Hamdi Abdelsalam¹, Takeshi Suzuki ² (1. Post doctor, 2. Professor (Associate))

Abstract: The two-spotted spider mite (TSSM), Tetranychus urticae Koch, is phytophagous and can alter the physiological processes of plants, causing impairment and yield losses. Chemical pesticides have been commonly applied to control TSSM, but the frequent use leads to the development of resistance, risks to human health, and environmental pollution. Nanoparticles have recently been used as carriers for RNAi-based biopesticides, and direct pesticidal activity is also known for silica nanoparticles. Here we tested the effect of colloidal silica nanoparticles (5-nm and 100-nm in diameter) on survival and fecundity of TSSM. Colloidal silica nanoparticles reduced the mite survival and fecundity, and these effects were independent of particle size but dose-dependent. Colloidal silica nanoparticles might reduce mites’ appetite and digestion, resulting in nutritional deficiencies. These results demonstrate a potential measure of colloidal silica nanoparticles to control TSSM.