For the molecular analysis, leaves were harvested and sub-sequently transferred into liquid nitrogen. Three leaves (centralposition) were harvested from each of the three different plants.The three leaves were pooled and represent a single sample out ofthe three biological replicates. Plants used for sampling leaves wereexcluded from subsequent imaging or additional leaf sampling. Leafsamples were taken on the same days as imaging. The pre-droughtsamples were used to establish a baseline of gene expression ofthe plants. All samples were taken at the same time of day (9 am),to minimize climatic variation (i.e. cloudy or sunny days), since at9 am the impact of the presence/absence of clouds is minimal forthe greenhouse microenvironment, being the time for warming-up of the greenhouse due to high sunlight limited to a few hoursafter sunset. In this manner the hydration state of the plants waspredominantly due to the availability of water in the vase and notdue to possible transient increases in transpiration at peak daytemperatures.