Spatial Risk Assessment of Xylella fastidiosa and Its Potential Vectors in South Korea Using Multiple Ecological Niche Models

Xylella fastidiosa is a high‐priority quarantine pathogen that poses a significant threat to a wide range of global agricultural crops across multiple subspecies and host associations, with Pierce's disease of grapevine representing one of its most economically devastating manifestations. The pathogen is of concern as it spreads through vectors, not all of which are known, emphasising the importance of early detection and phytosanitary surveillance. This study employed an ensemble of species distribution models (SDMs) to evaluate the potential distribution of X. fastidiosa and its vectors in South Korea to assess regional biosecurity risk, including the risk of Pierce's disease in grapevine‐producing regions. Models for X. fastidiosa and three potential vectors ( Aphrophora pectoralis , Bothrogonia ferruginea and Cicadella viridis ) were developed using CLIMEX and machine learning‐based models (MaxEnt, random forest and multilayer perceptron). Due to no local occurrence records of X. fastidiosa in South Korea, a globally trained model was first constructed and subsequently projected onto the Korean Peninsula. This model was integrated with weights based on performance evaluation metrics to develop an ensemble model, identifying high‐risk areas by analysing pathogen–vector suitability overlap, host cultivation zones and proximity to ports. Our results suggested that the central region of South Korea presents relatively higher suitability for X. fastidiosa establishment with potential vector occurrence, with B. ferruginea maintaining potentially broad suitability under future climate scenarios. This study presents an ensemble methodology for SDM of the disease and vectors, which could support early detection and phytosanitary surveillance for Pierce's disease.