Resistance to pathogens under variable temperatures

The biotic and abiotic environment of interacting hosts and parasites may vary considerably over small spatial and temporal scales. Jorgensen examines the effects of differing temperature and soil nutrient conditions on powdery mildew infection of Arabidopsis thaliana, and finds that there is a strong potential for a heterogeneous environment to change the resistance capacity of A. thaliana genotypes, and hence the direction and magnitude of selection in the presence of the pathogen. Transcription levels of RPW8, a resistance-conferring gene, increase after infection and vary between environments, but there is no tight association between transcription and resistance levels.