Using drone for chemical control of cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) in canola fields

. Canola, Brassica napus L. is a significant oilseed crop, containing 35 to 45% oil in its seeds, and can be cultivated in various climatic regions. Cabbage aphid, Brevicoryne brassicae L. is the most important pest of canola in Iran. Chemical insecticide application using ground sprayers is the primary method for controlling B. brassicae in canola fields. However, the dense and tall growth of canola plants poses challenges for maneuvering ground sprayers, which can potentially cause damage to the plants. Therefore, in this study, we evaluated the feasibility and efficacy of aerial spraying of canola fields against cabbage aphid using drone, and compared it with ground spraying. This study was conducted during two growing seasons in canola fields of Miandoab and Ilakhchi in northwest Iran. Aphid populations were sampled 24 hours before sprayings and 48 hours, 72 hours, and two weeks after sprayings. A six-rotor drone equipped with micronair rotary atomizers was employed for aerial spraying, while a tractor-mounted sprayer was used for ground applications. Results demonstrated that aerial spraying with drone was significantly more efficient, achieving two to six times higher efficacy against cabbage aphid than ground spraying, as measured by the reduction in aphid populations. Image analysis of water-sensitive cards indicated that drone produced finer droplets with smaller volume median diameters. Economic analysis revealed that aerial spraying was more cost-effective despite higher initial costs, due to lower operational expenses and reduced water usage. These findings underscore the potential of using drones for pesticide application in canola farming.