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.

Ozone is a powerful oxidant which can be used for killing insects and microorganisms. In this study, ozone was applied in the gaseous form to control two species of pests in stored dried figs. The samples of figs (50 g each) were infested with adults of Oryzaephilus surinamensis L. and larvae of Ephestia kuehniella Zeller and were subjected to different combinations of ozone concentrations (2, 3, and 5 ppm) and exposure times (15, 30, 45, 60, and 90 min). Changes in organoleptic properties (color, sweetness, firmness, aroma, and overall acceptability) during ozonation were studied. The results showed that the mortality rate increased with an increase in ozone concentration and exposure time. The total mortality of both pests was achieved at an ozone concentration of 5 ppm and exposure time of 90 min. Sensory evaluation showed that ozone only had a negligible effect on aroma. Therefore, the usage of ozone is recommended during the postharvest process instead of other chemical fumigants, such as methyl bromide and phosphine.

The essential oils, with known effects on insects, could be an alternative method to classical insecticides. In the present study, the essential oils of Agastache foeniculum (Pursh) Kuntze, Anethum graveolens L., Cuminum cyminum L., Foeniculum vulgare Gaetner and Satureja hortensis L. were isolated by hydrodistillation method using Clevenger apparatus and their insecticidal activities determined against Callosobruchus maculatus L. adults through fumigant bioassay. A culture of C. maculatus was established on the seeds of Vigna ungiculata at 27 ± 1°C and 65 ± 5 % relative humidity. Results indicated that the essential oils had high fumigant activity on the insect. Responses were different according to the plant materials and their concentrations. The LC 50 values of essential oils from A. foeniculum, A. graveolens, C. cyminum, F. vulgare and S. hortensis against C. maculatus were 25. 476, 12.750, 11.385, 24.944 and 68.728 μL/L air, respectively. On the other hand, the toxicity of oils followed in the order: C. cyminum > A. graveolens > F. vulgare > A. foeniculum > S. hortensis. The results demonstrated that the mortality rate of all essential oils increased with concentration increase. These results suggested that the essential oils extracted from A. foeniculum, A. graveolens, C. cyminum, F. vulgare and S. hortensis can be used in the management of C. maculatus in order to decrease the detrimental effects and risk of synthetic insecticides.

The current research was performed aiming to investigate the effects of Ferula ovina essential oil on the fourth instar larval hemogram of Sesamia cretica. Four main sorts of circulating hemocytes, including prohemocytes, plasmatocytes, granulocytes (GRs), and oenocytoides, were identified in the fourth instar larvae. Treatment of the larvae with the concentration of 1000 ppm of the essential oil led to an enhancement of the total hemocyte and GR count followed by a dose-dependent decrease at the concentrations of 2500 and 7000 ppm. Plasmatocyte numbers declined in all the treatments with more significant effects at increased doses. The greatest numbers of GRs, plasmatocytes, and total hemocytes were found after 48 h of treatment. The highest phenol-oxidase activity was recorded 12 h after treatment at the concentration of 2500 ppm. The highest effect on nodule formation was exerted by the concentration of 7000 ppm 12 h after treatment. The results of the present study clearly indicated that the treatment of larvae by the essential oil of F. ovina decreased the numbers of total and differential hemocyte counts although phenol-oxidase activity and the number of nodules showed no decline in the treated larvae. These results demonstrated that Ferula ovina essential oil has a significant effect on the immune ability of the studied insect and can be useful and usable for future research to practical management of this pest.

Microwave heating is an environmentally friendly method for killing pest insects and here its efficacy in the control of a pest species of dried fig and raisin was assessed. Dried fig and raisin samples were infested with Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) larvae and heated in a microwave oven at power outputs of 450, 720, and 900 W for 20, 30, 40, and 50 s. Following exposure to the microwave treatments, larval mortality and changes to organoleptic properties, which indicate consumer preference and include aroma, color, sweetness, acerbity, fragility, stiffness, and overall acceptability, were assessed. Our results showed mortality rates were greatest with the highest degree and duration of microwave exposure, where 100% mortality was recorded at 900 W with an exposure time of 50 s. The sensory evaluations of the fruit showed that microwave heating had some effect on aroma, color, fragility, sweetness, and overall acceptability, but no effect on acerbity and stiffness in dried fig, whereas in raisin, there were no impacts on acerbity, stiffness, or sweetness, but aroma, color, fragility, and overall acceptability were affected. We conclude that application of lower intensities of microwave treatment may provide acceptable levels of pest control in stored dried fruit without an associated trade-off in the reduction in quality of sensory attributes.

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The sublethal effect of spiromesifen on life table parameters of Neoseiulus californicus McGregor (Acari: Phytoseiidae) was evaluated under laboratory conditions 25±1 °C, 65±5% RH and 16:8 (L:D) h. To take both sexes and the variable developmental rate among individuals into consideration, the raw data were analyzed based on the age stage, two sex life table. The estimated values of LC5, LC10 and LC15 for N. californicus are found to be 5.834, 9.529 and 13.267 ppm, respectively. The total preoviposition period of N. californicus treated with sublethal concentrations of spiromesifen was not significantly longer than for the control treatment. The minimum total fecundity was recorded for the LC15 concentration of spiromesifen (19.37 eggs/female) that was significantly different to the LC5 and control treatments. Compared with the control, the intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R0) and gross reproduction rates (GRR) of mites treated by the dose of the LC15 concentration, decreased significantly but the mean generation time (T) was not affected by this sublethal concentration. Our results indicated that increasing concentrations of spiromesifen had significant negative effects on life table parameters of N. californicus.These quantities should not be used in combination with N. californicus in integrated pest management programs in order to obtain optimal of biological control conclusions.