Potential impact of climate change on plant–pathogen interactions

Abstract

How a rapidly changing climate may influence plant pathogens and the diseases they cause gained international prominence after Manning and Tiedemann (1995) first reviewed the impact of changing atmospheric CO2, O3 and UV-B on plant diseases. Two other publications considering changes in the biosphere and climate rapidly followed (Coakley 1995; Coakley and Scherm 1996). However, the effect of changing climate on plant diseaseswas assessed for NewZealand (Prestidge and Pottinger 1990) and the United Kingdom (Atkinson 1993) well before this and similar assessments have continued for other countries (Chakraborty et al. 1998), specific diseases/pathogens (Brasier and Scott 1994; Luo et al. 1995; Kaukoranta 1996; Bergot et al. 2004) and regions (Boland et al. 2004). Climate change effects on plant diseases have featured at many international meetings, including the Global Change and Terrestrial Ecology (GCTE) meeting at Reading in 1999 (http://mwnta.nmw.ac.uk/GCTEFocus3/ FoodandForest/99progr.htm). GCTE offers coordination among international groups for impact assessment (Scherm et al. 2000) on specific diseases such as potato late blight (Hijmans et al. 2000). Awareness among the plant pathology community was boosted by a session on this topic at the 7th International Congress of Plant Pathology (ICPP) in Edinburgh in 1998 (Chakraborty et al. 2000b). Since then there has been a session at the ICPP 2003 in Christchurch (Scherm and Coakley 2003) and one is planned for Turino in 2008. In Australia, a national workshop in 1997 addressed climate change impacts on economically significant plant diseases and a review was published in the Australasian Plant Pathology (Chakraborty et al. 1998). Although the topic has not yet sparked widespread interest among plant pathologists, new findings have continued to appear in plant pathology literature (Pangga et al. 2004) including novel approaches to impact modelling (Scherm 2004). Notable among recent empirical studies are diseases in natural plant communities using free air CO2 enrichment (FACE) (Percy et al. 2002), a field study on elevated temperature (Roy et al. 2004) and pathogen evolution (Chakraborty and Datta 2003). There have been important political developments too, none more significant than signing of the landmark Kyoto protocol and the recently announced ‘Asia-pacific partnership on clean development and climate’ between Australia, China, India, Japan, The Republic of Korea and the United States of America (http://www.pm.gov.au/news/media releases/media Release 1482.html). A plenary presentation by the author at the 15th Australasian Plant Pathology Society Conference, 26–29 September, 2005 in Geelong offered an opportunity to review current research and development in this area. This commentary reintroduces climate change to plant protection specialists, updates knowledge on its potential impacts on host-pathogen interactions to critically review progress and touches on future research needs in Australia to better manage diseases under a changing climate.