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Tetranychus urticae Koch (Acari: Tetranychidae) is a notorious crop pest with a worldwide distribution that has developed resistance to a wide range of acaricides. Combined tactics of pest management have special significance not only for a reduction in pesticide residues but also to maintain the natural enemy activity, which is an objective of IPM programs. Here, we investigated the effect of low-lethal concentrations of bifenazate at LC10, LC20, and LC30 on development and reproduction parameters of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae). Lethal and sub-lethal concentrations were estimated using leaf dip bioassay method. The crude data were analyzed based on age-stage, two-sex life table analysis. Toxicological assays showed bifenazate treatments gradually decreased the longevity and total life span of both sexes. Our results indicated that reproductive and total fecundity of the next generation were also affected by sublethal concentrations. All concentrations caused a significant decline in oviposition days, compared to the control. The intrinsic rate of increase (rm) varied from 0.1344 to 0.1151 day-1 for the mites treated with distilled water and LC30 treatments, respectively. The finite rate of increase (λ) was affected by the acaricide concentration (lowest at LC30 concentration: 1.1221 day-1). Bifenazate concentration (LC10, LC20 and LC30) treatments gradually reduced the gross reproduction rate (GRR) and net reproductive rate (R0). Based on obtained results from current study, bifenazate is not a favorable acaricide with A. swiriskii and cannot be recommended to use with this predatory mite in integrated management.

Tetranychus urticae (Acari: Tetranychidae) is one of the most important pests of agricultural crops with worldwide distribution causing considerable damage to different products. Application of chemical acaricides is one of the most important strategies used for the control of this pest. Entomopathogenic fungi, however, have been proposed as alternative control agents. In this study, sub-lethal effects (LC10 = 6.76 × 102, LC20 = 8.74 × 103, and LC30 = 55.38 × 103 conidia ml−1) of Beauveria bassiana strain TV on the life table parameters of T. urticae were evaluated under laboratory conditions. The results demonstrated that by increasing the concentration, a significant decline was observed in adult longevity of both male and female individuals. Total fecundity of T. urticae was calculated as 45.16, 36.28, 23.98, and 18.21 eggs in control, LC10, LC20, and LC30 treatments, respectively. Sub-lethal concentrations drastically affected the population parameters of this mite pest. The intrinsic rate of increase (r) ranged from 0.1983 to 0.1688 day−1 for the mites treated with distilled water and LC20 treatments, respectively. The net reproductive rate (R0) was affected by the sub-lethal concentrations (lower value at LC30 concentration: 11.19 offspring/individual). Considering the detrimental effects of B. bassiana on some biological parameters of T. urticae, it can be concluded that this product can be used to develop targeted interventions aimed at integrated pest management of this pest.

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Pesticides cause serious damage to agricultural and natural ecosystems. Knowing pesticides' side effects on non-target beneficial phytoseiids is crucial for integrated mite management (IMM) programs. One solution is to use biological agents and a low concentration of pesticides together. The present study was conducted to evaluate sublethal effects of acaricide Milbemectin (Milbecnock®) at LC5, LC15 and LC25 levels on development and reproduction parameters of Amblyseius swirskii Athias-Heneroit (Acari: Phytoseiidae) under laboratory conditions [25 ± 1°C, 70 ± 5% RH and 16:8 (L:D) hours]. Our results demonstrated that higher concentrations of Milbemectin (LC15 and LC25) had the most effect on the Longevity and the Total life span of both males and females of a predatory mite. The total life span in females was recorded from 42.67 days (Control) to 23.46 days (LC25 treatment). In an unusual observation, the oviposition period and also the total fecundity of the LC5 treatment have been 21.42 days and 37.31 offspring per individual, respectively. Which is recorded higher than the control treatment. These parameters were recorded in minimum value on the highest concentration treatment. Contrariwise the intrinsic rate of increase (r) and the finite rate of increase (λ) are not affected by sublethal concentrations of Milbemectin. The recommended dose of milbemectin based on the active ingredient is 10 ppm and the concentration obtained for LC5 is 27.92 ppm, which had a positive effect on fecundity and a slight imperceptible effect on the total life span reducing of the predatory mite. Sublethal effects of milbemectin and its impact on A. swirskii are discussed.

Knowledge of the effects of pesticides on biological control agents is necessary for the successful implementation of integrated pest management programs. Laboratory bioassays were conducted to evaluate the effects of Biomite®, a natural acaricide, on the life table parameters of Neoseiulus californicus McGregor (Acari: Phytoseiidae), as one of the most important natural enemies of Tetranychus urticae Koch (Acari: Tetranychidae) under laboratory conditions at 25 ± 2°C, 65 ± 5% RH and a photoperiod of 16:8 (L:D) h. The raw data were analyzed based on the two-sex life table theory. Biomite® concentrations LC10 and LC20 gradually and significantly reduced the longevity and total life span of both sexes, as well as total fecundity. Besides, concentration LC20 significantly reduced the gross reproductive rate (GRR) and the net reproductive rate (R0). However, the intrinsic rate of increase (r) and the finite rate of increase (λ) were not significantly affected. Thereby, due to an unfavorable shortened in life history characters of N. californicus such as total life span, reproductive periods and biological parameters (such as R0 and GRR), as a consequence of Biomite® treatment, it can be concluded that this acaricide should not be used with N. californicus in integrated pest management programs.

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae) is one of the most important pests of agricultural products. Using chemical pesticides is one of the main methods for its management. Due to undesirable effects of synthetic pesticides, this research was conducted to achieve alternative safe compounds. In this study sublethal effect of Atropa belladonna herbal extract including LC 10 , LC 20 , LC 30 and distilled water were evaluated on biological parameters (such as r, λ, GRR, R 0 and T) of T. urticae. The experiments were done under laboratory condition at 25±2 °C, 60±5% RH, and a photoperiod

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