Understanding pine wilt disease

The occurrence and epidemic spread of pine wilt disease （PWD） are influenced by multiple factors, including the pathogen （Bursaphelenchus xylophilus）, host plants, environmental conditions, human activities, vector insects, and associated microorganisms. These elements collectively constitute a complex plant disease system, referred to as the "PWD hexahedron." This review systematically summarizes the role of these six components in the development of PWD and proposes corresponding control strategies: 1） Pathogen （B. xylophilus）: The morphological characteristics, life cycle, and distribution of B. xylophilus in host trees are reviewed, along with recommendations for sampling and nematode identification; 2） Host plants: The range of susceptible and potential host species, as well as symptoms of infection, are discussed, providing insights into monitoring and sampling strategies; 3） Vector insects: The diversity, life history, and feeding and transmission behaviors of vector insects are examined, with recommendations for the identification of unknown vectors and detection of B. xylophilus in insect carriers; 4） Environmental factors: The influence of environmental conditions on the pathogen, vector insects, and disease epidemiology is analyzed, offering guidance on surveillance strategies; 5） Microorganisms: The associated microorganisms of B. xylophilus, vector insects, and host pines are reviewed, highlighting their role in PWD progression and their potential application in disease management; 6） Human factors: The impact of inadvertent long-distance spread, negative interventions, and positive management efforts is explored, emphasizing the need for regulatory measures. Given the complexity of this plant disease system, an integrated approach based on scientific prevention and control technologies, along with precise and systematic management strategies, is essential to achieve effective control of PWD.