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چکیده
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The predatory mite Amblyseius swirskii is widely used as a biological control agent against spider mites, thrips, and whiteflies. This study examined the sublethal effects of two abamectin concentrations (LC10 and LC20 for A. swirskii) on life history traits and demographic parameters of the F₁ generation derived from treated parents under controlled laboratory conditions (25 ± 1 °C, 75 ± 5% RH, 16:8 [L:D] photoperiod). Using the age-stage, two-sex life table approach with Tetranychus urticae Koch as prey, results showed that total longevity was shortest in progeny of LC20-treated parents (males=13.42 days; females=13.94 days) compared with LC10 progeny (males=15.06 days; females=15.50 days). Fecundity, oviposition period, and net reproductive rate (R₀) declined significantly with increasing acaricide concentration. Intrinsic and finite rate were reported to be increased in the treatments (r: 0.159 vs. 0.199 day⁻¹; λ: 1.172 vs. 1.221 day⁻¹). Age-specific survival (lₓ), fecundity (mₓ), and reproductive value (vₓⱼ) curves indicated pronounced adverse effects of sublethal exposure on population performance. These findings demonstrate that even low concentrations of abamectin can compromise key life history traits of A. swirskii, potentially limiting its effectiveness in biological control programs. Thus, evaluating acaricide compatibility with natural enemies is critical for successful IPM implementation.
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