The impact of climate change on disease in wild plant populations and communities

Disease in wild plant populations has received less attention from plant pathologists than diseases of managed plants in agriculture, horticulture, and plantation forestry. Plant ecologists, however, have contributed much to an understanding of how pathogens, other plant-microbe interactions, and arthropods affect population structure and community assemblages of wild plants. Consequentially, this lack of attention has meant that the potential impacts of climate change on disease in wild plant populations are less appreciated than on major food crops, where modelling of such impacts is now well established. However, plant ecologists and soil microbiologists have long studied long-term climatic effects through a combination of observational studies and manipulative field experiments. Here, strategies are discussed to bring together these different perspectives into an integrated approach to address the future impacts of climate change on plant, environmental, and ecosystem health. The approach taken will be first to note the temporal and spatial scales that can be considered, ranging from microhabitats to whole biomes, review what is known about climate change impacts on natural vegetation, referring briefly to climate change impacts on crop diseases, and then what is known about impacts in wild populations at both the individual species and also the ecosystem level. The more general area of plant-soil-microbe-pathogen interactions is covered as one of the more important areas where climate change may have much impact on plant health through indirect rather than direct effects. The special cases of introduced invasive plants and the connectedness of agricultural systems with the wider landscape are discussed.