The plant disease triangle facing climate change: a molecular perspective.

To cause disease in plants, pathogens not only require a susceptible host, but also often require specific environmental conditions suitable for pathogenesis. Multiple aspects of climate are predicted to change dramatically over the coming decades, which will result in increases in CO 2 and, depending on location, temperature, humidity, salinity, flooding, or drought. Climate change will result in increases in the prevalence, dispersal, and range of different plant pathogens, while simultaneously affecting the virulence mechanisms of microbial pathogens. The plant immune system can be compromised by extremes in climatic conditions and crosstalk with abiotic stress signaling pathways. Several recent reports have unraveled how climatic factors affect plants at the molecular level, raising the possibility of modifying these pathways for climate-smart, pathogen-resistant crops. Variations in climate conditions can dramatically affect plant health and the generation of climate-resilient crops is imperative to food security. In addition to directly affecting plants, it is predicted that more severe climate conditions will also result in greater biotic stresses. Recent studies have identified climate-sensitive molecular pathways that can result in plants being more susceptible to infection under unfavorable conditions. Here, we review how expected changes in climate will impact plant–pathogen interactions, with a focus on mechanisms regulating plant immunity and microbial virulence strategies. We highlight the complex interactions between abiotic and biotic stresses with the goal of identifying components and/or pathways that are promising targets for genetic engineering to enhance adaptation and strengthen resilience in dynamically changing environments. [ABSTRACT FROM AUTHOR]