Dothistroma needle blight and pitch canker: the current and future potential distribution of two important diseases of Pinus species

Globally, pitch canker and Dothistroma needle blight are two of the most important diseases of pine species caused, respectively, by the pathogens Fusarium circinatum Nirenberg & O'Donnell and Dothistroma spp. (Dothistroma septosporum (Dorog.) Morelet and Dothistroma pini Hulbary). The potential distributions of these two diseases under current global climate have previously been modelled and contrast strongly with each other. In this study, we used the process-based niche model CLIMEX to estimate the potential distribution of both diseases in the 2080s under six scenarios that include three contrasting global climate models, each with moderate and high CO2 emissions. For both diseases, under the future climate scenarios, there was a global reduction in the potentially suitable area. Among the three global climate models, this reduction ranged from 11% to 22% for Dothistroma needle blight and from 39% to 58% for pitch canker. The projected potential ranges of both diseases were significantly reduced for Africa, South America, and Australia. In Asia and North America, substantial reductions in potential area were generally projected for pitch canker, while little change to moderate levels of expansion were projected for Dothistroma needle blight. For Europe and New Zealand, expansion of suitable climate was projected under all climate change scenarios for both diseases.