Can unmanned aerial vehicle (UAV) adoption reduce pesticide use and enhance yields? Evidence from mountainous rice farming in Yunnan, China

Enhancing food security while reducing pesticide use is central to sustainable agricultural development. Mountainous regions, characterized by fragile ecosystems and intensive pesticide use, present a major challenge. This study investigates how the adoption of unmanned aerial vehicles (UAVs) affects pesticide expenditure and rice yields in such regions, using data from 520 rice growers in Yunnan province, China. Employing a conditional mixed process model, we find that UAV adoption reduces pesticide expenditure by 77.3 yuan/mu and increases rice yields by 196.9 kg/mu. Disaggregated analyses reveal that the pesticide reduction effect due to UAV adoption is more pronounced among farmers with smaller landholdings and those cultivating fertile soil. Rice farmers cultivating large and fertile farmland receive more yield improvement from using UAVs for pesticide application. Quantile regression further indicates that the positive impacts of UAV adoption are greater among farmers with higher initial pesticide use and yields. Moreover, a higher intensity of UAV use is significantly associated with lower pesticide costs and greater rice output. These findings suggest that policies should promote UAV adoption and support deeper integration into farming practices to maximize environmental and productivity gains. Targeted subsidies, training programs, and financial incentives—especially for smallholder farmers in mountainous regions—can accelerate adoption and ensure equitable access. Moreover, fostering local UAV service providers and strengthening rural infrastructure can further enhance the efficiency and scalability of precision agriculture in challenging terrains.