The sequence of drought-induced physiological and anatomical events in woody perennial crops

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Canada's agri-food sector is facing unprecedented challenges caused by drought due to ongoing climate change. The 2001 to 2002 national drought has resulted in $3.6 billion in losses in agricultural production and gross domestic product fell by around $5.8 billion. The 2017 drought resulted in the worst wildfire season in British Columbia with severe negative impacts on crop yield and quality. Crop performance under drought depends on a successful coordination of processes at root, stem, and leaf level. This includes efficient stomatal regulation and root suberization to avoid excessive water loss to the atmosphere and soil, respectively. Drought-induced mortality is predominantly linked to xylem hydraulic failure by gas embolism blocking water transport from roots to leaves. Knowledge about the sequence of drought-induced physiological and anatomical events will facilitate (a) the selection of crop genotypes with improved drought resistance and (b) the development of sustainable irrigation practices. My recent research into drought stress responses of woody perennial crops has resulted in a novel approach to predict process-specific stress thresholds at leaf level, elucidated in-vivo stem xylem embolism susceptibility and storage, and revealed that embolism repair is not driven by root pressure. The long-term objective of my research program is to elucidate crop water requirements to promote sustainable agriculture through water savings. Within my program, the short-term objectives are to (a) identify stress thresholds associated with stomatal closure and turgor loss, (b) determine the coupling of xylem water transport and storage, and (c) identify the dynamic changes in root water uptake in response to drought stress. I will use a combination of traditional and cutting-edge measurement tools to elucidate crop performance under drought. X-ray computed microtomography at Canadian Light Source will provide unprecedented insights into xylem function, embolism susceptibility/repair in-vivo, and 3D plant anatomy. Fluorescence light microscopy will be used to investigate cell viability of cambium and parenchyma. Root hydraulic function and water transport pathways will be assessed using pressure probe methodology. Using a Scholander-type pressure chamber, the water potential method will be used to determine water status, stress thresholds, and plant dehydration stages. A mini-lysimeter platform will be established to control soil moisture and monitor plant water loss by transpiration. My research program provides opportunities for 3 PhD, 3 MSc, and 5 undergraduate students. My research team will be composed of diverse HQP where lab members can thrive as teammates. This will create a lab environment that supports the collaborative nature of science. I will ensure that everybody is treated fairly (equity) and feels part of the research team (inclusion) with equal opportunities for HQP to achieve scientific and professional goals.