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Insecticides can have unintended effects on non-target insects, such as natural enemies. In this study, the effects of several recommended insecticides against wheat pests on the flower fly Episyrphus balteatus and the seven-spotted ladybird Coccinella septempunctata, which are active generalist predators in fields, were investigated. The experiment was conducted in a completely randomized design with eleven treatments and three replications, under laboratory conditions at a temperature of 24 ± 2°C, relative humidity of 50-60%, and a photoperiod of 16:8 (light: dark). The treatments included the insecticides fenitrothion (0.5, 1, and 2 ml/L), deltamethrin (0.15, 0.3, and 0.7 ml/L), matrine (0.7, 1, 1.5, and 2 ml/L), and a control (water). The mortality rate of the pupae of the flower fly and the pupal and adult stages of the ladybird were examined, and the insecticides were categorized according to the IOBC method. The results showed that the most significant negative effect on the flower fly was caused by fenitrothion 2 ml/L, which resulted in a 32.32% mortality. However, as the concentration was reduced, the mortality rate significantly decreased. Deltamethrin 0.7 ml/L and matrine 2 ml/L caused mortality rates of 19.39% and 13.47%, respectively, in the flower fly, while lower concentrations of these compounds did not induce any mortality. Regarding the effects of treatments on the ladybird, all three concentrations of deltamethrin and fenitrothion caused 100% mortality in adult ladybirds, whereas matrine caused no mortality in adults. For pupae, deltamethrin induced 100% mortality across all concentrations. Fenitrothion’s effects on pupae were significantly dose-dependent, with 100%, 82.2%, and 50% mortality observed at concentrations of 2, 1, and 0.5 ml/L, respectively. Increased concentrations of matrine also led to a significant rise in pupal mortality, with matrine at 2 ml/L causing over 81% mortality, placing it in the moderately harmful category. In general, all treatments tested were considered harmless to flower fly pupae, except for fenitrothion 2 ml/L, which was classified as slightly harmful. Regarding the ladybird, deltamethrin was harmful to both adult and pupal stages. Fenitrothion was harmful to adult ladybirds at all concentrations, with its effects on pupae increasing with concentration. Matrine was harmless to adult ladybirds but showed adverse effects on their pupae, with these effects intensifying as concentration increased. Based on the results, it is recommended to avoid increasing the application concentration and refrain from using these insecticides during peak periods of natural enemy populations, specially the seven-spotted ladybird.
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