PS Webinar Series - PhD Exit Seminar: Plant hydration dynamics: measurement and uptake pathways

Abstract - Most water fluxes on the land occur through plants via transpiration, and agriculture uses 70% of the water managed by humans. Better knowledge of plant water status could help improve climate models and increase water use efficiency in agriculture, but most available tools are not suitable for these tasks. During my PhD, I studied the loss and recovery of plant hydraulic function during dehydration-rehydration cycles. By studying the effects of tissue damage on the osmotic and elastic properties of leaves, I became frustrated with the pressure-bomb technique and with the unintuitive interpretation of ‘relative water content’, which are amongst the most widely used techniques and metrics to quantify plant water status. My frustration led me to develop (1) a way to measure turgor pressure and leaf thickness directly, via uniaxial compression; and (2) a more intuitive metric for quantifying swelling and shrinking of plant tissues. Notably, uniaxial compression provides accurate measurement of plant water status with high temporal resolution at low cost, and can be automated and applied to intact tissues. In my Exit Seminar I narrate the inquiry process of my PhD and discuss potential applications of my findings.

Biography - I went to university in Chile, first studying psychology and social sciences. Elective courses in natural sciences eventually led me to drop social sciences and pursue a degree in agronomy. While doing my undergrad I volunteered in a few research labs and was captivated by the inquiry process of experimental science. Courses and colloquiums in Parque Katalapi boosted my motivation to do a PhD and eventually brought me to Canberra to work with Prof. Marilyn Ball. During my PhD, I became fascinated by the links between plant biomechanics and water content in plant tissues. My current interests include the biomechanics of soft plant tissues, their link with plant physiological function, and the use of robotic systems to measure the growth and water pulses of plants.