Comprehensive investigation of the toxicological and behavioral effects of various inert dusts on Sitophilus granarius

In this study, toxicological and behavioral effects of particular inert dusts (bentonite, halloysite, nobleite, kaolinite, sepiolite, and zeolite) on the infestation of Sitophilus granarius in wheat grains were evaluated under controlled laboratory conditions. The experiments comprised a single-dose screening test, dose-response studies, and assessments of other effects. Kaolinite and nobleite displayed remarkable efficacy, causing 100.00% mortality after 120 h (5 days) at 2000 ppm in the single-dose screening, leading to their selection for further tests. A subsequent dose-response study revealed LC₁₀, LC₂₅, and LC₉₀ values for nobleite and kaolinite at concentrations of 380, 875, 12,788 ppm, and 360, 618, and 3574 ppm, respectively. Lethal time (LT₅₀) calculations at the LC₂₅ dose resulted in 169.64 h for nobleite and 148.86 h for kaolinite. The investigation into the behavioral effects of nobleite and kaolinite uncovered insignificant repellent effects compared to the control group but revealed significant antiovipositional effects. Strong negative correlation (r = -0.949) emerged from the correlation analysis between inert dust particle sizes and antifeedant effects. Kaolinite and nobleite prove to be satisfactory alternatives for stored grain pest control.