Increased risk of pitch canker to Australasia under climate change

Pitch canker is a varied and complex disease of Pinus species. Despite the establishment of this disease in many countries, it has been difficult to predict how Fusarium circinatum would behave if introduced into Australia or New Zealand. To understand the potential risk this pathogen poses to the forest industries in Australasia, the process-oriented niche modelling program CLIMEX was used to model the climate suitability for pitch canker establishment using a current climate dataset and three contrasting global climate models (GCMs) under moderate and high CO2 emissions scenarios. Under current climate, the northern coastal areas of New Zealand and the moist periphery of Australia appear climatically suitable for pitch canker. Under all of the climate change scenarios examined it is projected that the potential distribution of pitch canker would expand southwards to include most of the extensive forests presently located in the central North Island of New Zealand and the northern areas of Tasmania. Under current climate these areas appear climatically unsuitable for pitch canker due to excessive cold stress and/or insufficient annual heat sum. The results identify the extent of risk posed to Australasia by F. circinatum and highlight the need for continued efforts to prevent the introduction and establishment of this pathogen in Australasia.