Carbon Up, Nutrients Down: From the Ionome to Protein in a Grass Under Rising CO₂

Rising atmospheric CO₂ stimulates photosynthesis in C₃ plants but often reduces the concentrations of essential nutrients in their tissues, raising concerns about the nutritional quality of staple cereals. Although these declines have been widely documented in field experiments, the underlying physiological mechanisms remain debated. In this seminar, I examine these responses in the model grass Brachypodium distachyon. I first show that elevated CO₂ reduces the concentrations of a broad range of elements. Among them, nitrogen and the protein it supports are the most consequential for nutritional quality. I then address a central mechanistic question: does elevated CO₂ reduce protein accumulation by limiting nitrate assimilation, and can ammonium nutrition mitigate this effect? To answer it, I integrate whole-plant physiology with root and shoot multi-omics across nitrogen forms, three accessions, and two growth temperatures, and use network analyses and interpretable machine learning to identify the molecular processes associated with shoot protein accumulation. Finally, I discuss the implications of these findings for nitrogen management and for developing cereals with improved nutritional quality under rising atmospheric CO₂.

Speaker: Dr. Hsin-Fang Chang (Assistant Professor, Department of Plant, Soil and Microbial Sciences, Michigan State University, USA)

Host: Dr. Kuo-Chen Yeh

Time:2026/12/08 11:00 AM

Location:Auditorium A134, Agricultural Technology Building