Gremmeniella abietina: a Loser in the Warmer World or Still a Threat to Forestry?

Abstract

Abstract Purpose of Review Gremmeniella abietina is a destructive forest pathogen responsible for Scleroderris canker, shoot dieback, defoliation, and tree death in forests and tree nurseries. This review is aimed at providing a complete description of the fungus, its distribution, the conditions for its spread, and the impact of climate change and at summarising the relevant forest management methods. Due to the worldwide importance of the pathogen, a retrospective review is required to summarise the lessons learned in relation to the disease, considering application to future outbreaks. Recent Findings We revise available management methods, considering examples of control strategies, with special focus on the silvicultural approaches, and we also revise the recovery of the affected stands and the associated trade-offs. Forest disturbances such as pests and disease outbreaks are expected to be exacerbated by climate change, although the exact impact on all host-pathogen interactions remains unclear. In regions with a high risk of G. abietina epidemics, climate change is expected to affect the pathogen differently. Summary Gremmeniella abietina is a widely distributed forest pathogen in Europe and is also present in North America. Based on the conclusions reached in this review, forest stands may recover from pathogen outbreaks within 10 years, with considerable loss of growth and the risk of attack from secondary factors. Provenance selection is vital for preventing outbreaks. Climate change is expected to have different effects: in some areas, it is likely to increase the conditions conducive to the development of the fungus, while in others, it is likely to limit the spread because of high temperatures and low humidity. Preventing future outbreaks of this pathogen requires the use of mitigating strategies, together with forest monitoring, forecasting, and planning.