Persian Journal of Acarology

Abstract The European red mite, Panonychus ulmi (Acari: Tetranychidae) is one of the main pests of apple trees worldwide. The main purpose of this research was to study the repellent and lethal effect of Heracleum persicum Desf. and Trachyspermum ammi L. essential oils (EOS) on the European red mite. The EOS of H. persicum and T. ammi were extracted using a Clevenger device and by water distillation method. The mortality of the mites was evaluated after 24 hours and the lethality of each EO was calculated in contact and fumigant toxicity in an incubator at 26 ± 2 °C temperature, 16:8 h L:D, and 50 ± 5% RH. It was found that the LC50 values of EOS of H. persicum and T. ammi were 343.91 and 311.74 µL l-1 for contact toxicity, and 2.54 and 2.85 µL l-1 air for fumigant toxicity, respectively. With increasing the concentration of EOS, the death rate of mites was increased. Three different concentrations of the EOS from H. persicum and T. ammi were tested for their repellent effects on the European red mite. Results of the present study revealed, that the repellency rate increased with increasing concentration, meanwhile, the T. ammi EO had the highest repellency among the concentrations.

Abstract This study investigates the lethal and sub-lethal effects of the pesticides fluxametamide and Sero-X on the predatory mite, Neoseiulus californicus (McGregor). As a key biocontrol agent, N. californicus is crucial in regulating mite pest populations and small insects like thrips. Understanding the effects of these pesticides is essential for maintaining effective biological control strategies. In an integrated pest management (IPM) program, selecting low-risk pesticides that target pests while preserving beneficial organisms is critical. To assess these effects, bioassay tests were conducted under controlled laboratory conditions (25 ± 2 °C, 65 ± 5% RH, and a 16:8 light-dark photoperiod). Lethal bioassay test results showed that the LC50 values of fluxametamide and Sero-X on adults of N. californicus were 1421 mg/L and 2169 mg/L, respectively. The results showed that exposure to the LC30 concentration of either fluxametamide or Sero-X significantly affected the predator’s reproduction and developmental parameters. Both treatments reduced life table parameters (r, R₀, λ, and GRR) while increasing generation time (T) compared to the control. Additionally, maternal exposure influenced progeny life history in varied ways. These findings highlight the need for sustainable pest management that minimizes chemical impact while preserving ecological balance, ensuring natural predators remain effective in agriculture.

Abstract European red mite, Panonychus ulmi (Acari: Tetranychidae) is one of the main pests of apple trees worldwide. The main purpose of this research was to study the lethal and sub-lethal effects of Salvia officinalis and S. rosmarinus essential oils (EO_S) on the European red mite. It was found that the LC₅₀ values of EO_S of S. officinalis and S. rosmarinus were 581.95 and 460.67 µL l⁻¹ for contact toxicity, and 3.40 and 4.03 µL l⁻¹ air, for fumigant toxicity respectively. With increasing the concentration of EO_S, the death rate of mites was increased. To study the lethality of S. officinalis and S. rosmarinus EO_S on the European red mite, concentrations of the LC₂₅ values of the mentioned EO_S were 443.32 and 273.48 µL l⁻¹, respectively. The net reproductive rate (R₀) in the control and in the treatment with S. officinalis and S. rosmarinus EO_S were 5.18 ± 0.94, 3.12 ± 0.49 and 3.28 ± 0.51 offspring/female/ individual, respectively. The intrinsic rate of increase (r) in the control and in the treatment with S. officinalis and S. rosmarinus were 0.10 ± 0.01, 0.07 ± 0.01, and 0.07 ± 0.01 day⁻¹, respectively. The finite rate of population increases (λ) in the control and the S. officinalis and S. rosmarinus treatments were 1.11 ± 0.13, 1.07 ± 0.07 and 1.08 ± 0.07 day⁻¹, respectively, which were significantly smaller than the control. The results showed that both tested EO_S have lethal and sub-lethal effects on the European red mite, whereas, S.rosmarinus EO caused significantly more casualties compared to S. officinalis EO. Also, the effect of S. rosmarinus EO in reducing parameters such as the immature longevity, female longevity, and fertility was estimated to be greater than that of S. officinalis EO. Finally, the mentioned plant compounds have noticeable effects on the age-stage specific survival and fertility rates in the European red mite and possess the capability of significantly reducing its population under controlled condition.