Considering that wood is an incredibly valuable source of renewable biomaterial and biofuel products, it is essential that we understand how the underlying mechanisms that drive wood formation function, to apply this knowledge to the improvement of the quantity and quality of wood. Therefore the aim of this study was to investigate how Eucalyptus grandis genetic mechanisms influence stem morphology during prolonged water deficit, and how this governs tree physiology. Changes in morphological features, gene expression and protein translation were compared between E. grandis plants that experienced drought and well-watered conditions. Upon completion of the growth experiments, stem samples were harvested from the trees to 1) analyse the wood anatomy by preparing thin transverse cross sections and imaging on a fully automated light microscope, 2) determine lignin composition using the Klason’s lignin method and 3) perform transcriptomic analysis via Illumina RNA sequencing and a bioinformatics pipeline. In brief, the drought treatment resulted shorter plants with thinner stems and these plants had a highly negative leaf water potential and reduced stomatal conductance. The wood anatomy data suggested that the anatomical adaptation to drought in E. grandis is geared towards higher implosion resistance and an increased ray network reach to effectively distribute water, carbohydrates, lipids, and ions throughout the xylem during abiotic stress. In addition, these physiology and anatomy processes were underpinned by the genetic expression.
