[Relationships between summer drought and strong typhoon events and pine wilt disease occurrence in East Asia]

The occurrence and prevalence of pine wilt disease cause huge losses to Japan, China, and South Korea in East Asia, and have received concerns from many countries. By the methods of field observation and meteorological data analysis, this paper studied the characteristics of the occurrence and prevalence of pine wilt disease and their relations to the meteorological disaster events. In Japan, China and South Korea, the meteorological extreme events of persistent summer drought and strong typhoon could trigger the occurrence of pine wilt. In extremely dry and hot environment, pine trees often appeared energy metabolism imbalance and entire tree wilt. However, in the years with lower temperature and more rainfall, less or nearly no pine wilt event occurred. It was suggested that before the attack by pine wood nematode and its vectors, the vigor of the pines had already declined, and thus, pine wilt disease could be confined in the areas often hit by summer drought and strong typhoon events. In the areas with suitable natural environment characterized by less summer drought and strong typhoon events and no improperly enlarged pine planting, there would be little possibility of widespread occurrence of pine wilt disease.