Developmental plasticity of Arabidopsis thaliana accessions across an ambient temperature range

The global increase in ambient temperature constitutes a significant challenge to wild and cultivated plant species. Yet, a comprehensive knowledge on morphological responses and molecular mechanisms involved is scarce. Studies published to date have largely focused on a few, isolated temperature-relevant phenotypes such as flowering time or hypocotyl elongation. To systematically describe thermomorphogenesis, we profiled more than 30 phenotypic traits throughout an entire life cycle in ten distinct accessions of Arabidopsis thaliana grown in four different ambient temperatures. We observed a uniform acceleration of developmental timing in the vegetative growth phase with a low contribution of genotype effects on variation indicating a passive effect of temperature. In contrast, reproductionassociated phenotypes and several quantitative growth traits were sensitive to both, genotype and temperature effects or could be attributed primarily to either factor. Therefore, the results argue against a general mechanism of passive temperature effects by thermodynamic processes. Temperature responses of several phenotypes rather implicate differential function of specific signaling components that might be targets of adaptation to specific environmental conditions. Keyword index ambient temperature, thermomorphogenesis, natural variation, phenotypic plasticity 2 . CC-BY-NC 4.0 International license not peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was . http://dx.doi.org/10.1101/017285 doi: bioRxiv preprint first posted online Mar. 30, 2015;