Yanli Zhang
Swiss Federal Institute for Forest, Snow and Landscape Research WSL
Yanli Zhang is a PhD student in tree ecophysiology at Swiss Federal Institute for Forest, Snow and Landscape Research WSL and Federal Institute of Technology Zurich ETH Zurich. Her research is centered on understanding the dynamics of non-structural carbohydrates (NSCs) in trees, with a particular focus on carbon source–sink relationships and their implications for carbon starvation under stress conditions. She is exploring innovative approaches, such as sugar infusion, to mitigate carbon starvation in trees. By experimentally manipulating NSC levels, she aims to gain insights into the potential of sugar supplementation as a tool to enhance tree resilience against environmental stress and to improve forest management practices in the face of climate change.
Title of presentation
Sugar infusion in trees: possibility and effects
Authors
Yan-Li Zhang, Yue Yang, Mai-He Li
Forest Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Birmensdorf, Switzerland
Abstract
Carbon (C) starvation has been proposed as a possible physiological mechanism underlying drought-induced tree mortality. However, directly testing this hypothesis through experiments is currently not feasible due to the lack of suitable methods. To address this problem, we infused 13C-labeled glucose into C-limited trees via phloem or xylem and traced its allocation, to study whether C-limited trees accept, allocate and utilize exogenous sugar added. Our results showed that C-limited trees take up and translocate the infused exogenous glucose, and that xylem infusion is more effective than phloem infusion. Increased δ13C in dark respiration and tissue cellulose confirmed that trees utilize the infused glucose for maintenance and biomass growth. Sugar infusion significantly increased the concentration of leaf non-structural carbohydrates, followed by leaf senescence. This suggests that excessive sugar addition and thus sugar accumulation triggers negative feedback in photosynthesis. Our findings demonstrated the possibility of experimentally testing the carbon starvation hypothesis through adding exogenous sugars to C-limited trees. Furthermore, it has great potential for practical applications, such as adding sugars (or solutions) to save severely damaged historic and landmark trees.