Pine wilt in meteorological hazard environments

Abstract

Environment plays an important role in the interaction between host and pathogen and in the expression of diseases. Climatic differences among East Asia, Eastern USA, the Mediterranean and Northern Europe were compared against differences in the prevalence of pine wilt disease. This disease was prevalent in East Asia where there are frequent summer droughts and typhoons. Northern Europe (EEM) has a mild climate with very few summer droughts and tropical cyclone impacts and no pine wilt disease. The Mediterranean occasionally suffers climatic extremes, and pine wilt disease occurs infrequently and in localized area. The Eastern USA has climatic variability intermediate between Northern Europe and East Asia. Hurricanes are fewer and weaker compared to typhoons in Japan, China and Korea. Pine wilt disease occurs only in exotic pines in the USA. The climate of Hokkaido in Japan, where there is no pine wilt disease, is similar to that of the Eastern USA. With special stress adaptability, pines (Pinus spp.) usually respond to the meteorological extremes entirely and excrete large amount of resin. Disturbing by the hazardous summer drought and strong rainless typhoons (foehn-like typhoon), water and energy imbalance of pines often occurred so as to halt the resin excretion and trigger them into wilt.