Could you tell us a bit about yourself and your academic background?
I came to Australia for my undergraduate studies after I finished high school in China. I studied viticulture and winemaking for my Bachelor’s (hons) Degree at the University of Adelaide. In my honours’ year, I worked on a project about berry cell death: measurement using impedance spectroscopy. I thoroughly enjoyed this learning experience and I decided to continue exploring and further my research skills by starting a full time PhD with the first ARC Training Centre for Innovative Wine Production (ARC TC IWP) in the fields of viticulture and plant physiology.
My PhD further investigated berry cell death. We used various techniques to understand the physiological cause for berry cell death. Cell death in the mesocarp of berries occurs late in the ripening process, it’s associated with pre-harvest berry shrivel and this may influence berry sensory attributes. Using advanced techniques, such as molecular oxygen sensing and Micro-CT, we found that oxygen concentration inside grape berries declines during ripening and is correlated with the pattern of mesocarp cell death. Lenticels on the pedicel provide a pathway for oxygen diffusion into the berry. The data generated in this study provides the basis for further research into the role of berry gas exchange on berry quality and cultivar selection for adapting viticulture to a warming climate.
Now I am working as a Postdoctoral Researcher in the new ARC TC IWP studying the vascular transport system in grapevines.
Could you introduce us to your project and what it involves?
The vascular system transports water, nutrients and sugars in grapevines and it plays an important role in berry growth and quality. We want to establish this study by looking at a few aspects. First we used fluorescent microscopy to examine the vascular patterns (both xylem and phloem) inside developing berries across a number of varieties, including seeded and seedless. This knowledge is currently lacking maybe due to the difficulties in phloem imaging.
Second and also the current focus is developing a method to monitor vascular flow in living potted vines using Magnetic Resonance Imaging (MRI) in collaboration with the Nanoscale Organisation and Dynamics Group at Western Sydney University (WSU) and the National Imaging Facility at the Biomedical Magnetic Resonance Facility, WSU.
The flow rate within the vascular conduits could reveal how vascular flows behave during grapevine development. We hope the new knowledge will help us better understand fruit growth and provide leads in finding ways in better controlling yield and berry quality in the vineyard. Our preliminary results showed that we can use the technique to study the fine vascular structures non-destructively in living vines. The initial MRI scans have also revealed a relatively low rate of xylem flow in a potted grapevine. Currently we are fine-tuning the methodology, using a phantom system made up of grapevine canes and applied water pressure, to acquire precise flow signals. Later on, we will examine diurnal and developmental changes in vascular flow in the grapevine, as well as how the changes are subjected to abiotic stresses.
With additional funding from the Wine Australia Incubator Initiative and in collaboration with industry partners, we conducted a field trial in the growing season of 2018/2019 in the Coonawarra region. This trial investigated the effectiveness of using rootstocks to limit potassium, a phloem mobile element, uptake of Cabernet Sauvignon grapes, in order to manage acidity of berry juice and ultimately of the must and wine. Read more about this research here.
What can you see yourself doing in the future?
I really enjoy my research, it gives me opportunities to keep learning new methods and techniques in multiple disciplines. I’m surrounded by brilliant people in the research world and the grape and wine industry. I hope I can keep journeying with this community to add new knowledge and optimise viticulture in this changing climate.