Evaluation of High-Efficacy Insecticides and Control Efficacy Using UAV Application Against the Sea Buckthorn Fruit Fly, Rhagoletis batava obscuriosa

Aiming at addressing the lack of efficient, low-toxicity insecticides and precise application technologies in the current control of R. batava obscuriosa, this study intends to screen high-efficacy insecticides for UAV application and evaluate their field control effects, so as to provide a reference for the field control of R. batava obscuriosa. The residual film method was used to determine the laboratory toxicity of seven insecticides to adult R. batava obscuriosa. The LC50 and LT50 values of the seven insecticides were calculated. Based on these results, four high-efficacy insecticides were selected for UAV field efficacy testing. The control effects of different insecticides were evaluated through indicators such as population reduction rate, corrected control effect and fruit infestation rate after application. Laboratory toxicity results showed that 10% abamectin·beta-cypermethrin exhibited the strongest toxicity at 24 h (LC50 = 22.108 mg/L). At 48 h after application, 5% emamectin benzoate was optimal (LC50 = 5.486 mg/L). At 72 h after application, 10% broflanilide (LC50 = 1.796 mg/L) and 10% abamectin·β-cypermethrin (LC50 = 2.665 mg/L) performed best. Field test results indicated that the population reduction rate of 10% abamectin·β-cypermethrin reached 91.73% at 7 days after application, while the other three insecticides had population reduction rates above 80%, showing good overall control effect; at 15 days after application, 20% chlorfluazuron-thiamethoxam had the highest corrected efficacy (80.91%), and the fruit infestation rate of each insecticide group (24.75–27.49%) was significantly lower than that of the control group (58.08%). All four selected insecticides can effectively control the population of R. batava obscuriosa adults and can be used as quick- and long-acting insecticides against R. batava obscuriosa in production. Combined with UAV application technology, they can achieve efficient control of R. batava obscuriosa.