Current status and future prospects of agricultural drones in multi-scenario application in China

Agricultural production is often required to enhance the resilience and labor efficiency for the high-quality development, particularly with the accelerating population aging and the increasing frequency of extreme climate events. Conventional field operation and agricultural machinery cannot fully meet the demands of large-scale, efficient, and sustainable agriculture. Consequently, the advanced agricultural equipment has also limited the conventional practices. The agricultural drone has rapidly emerged under the broader transformation, due to its operational efficiency, flexibility, rapid deployment, and intelligent sensing. Meanwhile, drone technology can integrate with digital farming for the shift toward data-driven and intelligent agriculture. The drone has also been one of the most important components in smart and precision agriculture. This review was performed on the development pathways and application practices of agricultural drones in the United States, Japan, South Korea, and Europe. The trajectories also depended on the diverse agricultural structures, technological, and policy environments. Drone spraying was adopted early in Japan and South Korea, indicating the small-scale farming and advanced automation technologies. The United States was supported by large-scale mechanization and advanced remote sensing, with emphasis on the high-resolution monitoring and precision input management. European countries prioritized environmental sustainability and regulatory frameworks, thus resulting in broader applications, such as ecological monitoring, variable-rate operations, and compliance-oriented agricultural practices. These experiences provided important insights into agricultural drones in China. The agricultural drone industry was driven by the coordinated influence of expanding market demand, intelligent manufacturing, and strong policy support. Subsidies, standardization initiatives, and training programs also accelerated technology and regulatory adoption. As a result, both the number and scale of agricultural drones were increasing during operation in China. More importantly, an industrial ecosystem included the mass manufacturing, specialized service providers, professional pilot training and certification, maintenance, and data-driven agricultural decision-support platforms. The ecosystem facilitated the continuous and widespread application of agricultural drones over different crop types and production regions. Furthermore, a systematic overview was performed on the practical applications of agricultural drones under key agricultural scenarios. Low-altitude remote sensing was employed to monitor the crop growth dynamics, pest and disease, soil moisture, and nutrient variability for the high-resolution maps. Precision spraying was used for pest, disease, and weed control under crop growth regulation. Input efficiency was then improved to reduce the environmental impact. Multi-sensor fusion technologies were also used for intelligent obstacle avoidance, autonomous navigation, and adaptive route planning. Drift-control mechanisms enhanced spraying accuracy for the low off-target deposition. Agricultural drones also supported the quantitative and variable-rate broadcasting of seeds and fertilizers, thus contributing to more precise crops and resource management. Additional applications included the low-altitude logistics delivery over the challenging terrains, fruit harvesting in orchards with complex canopies, and aerial-assisted pollination for crops with supplemental pollination support. Agricultural drones have rapidly evolved under the influence of emerging technologies, including artificial intelligence, machine vision, digital twins, onboard edge computing, and swarm intelligence. Agricultural production also shifted from manual operation, single-function machinery, to multifunctional autonomous platforms under the complex tasks with minimal human intervention. Application scenarios continued to expand for the technological ecosystem under minimum resource consumption. The agricultural drone can be expected to enhance the productivity, ecological sustainability, and digital and intelligent transformation of modern agriculture.