Dynamic changes of rice sheath non-structural carbohydrates and source-sink balance under elevated atmospheric CO2 concentration and temperature stresses

Hao He; Jiabin Shi; Mingjie Chen; Jing Zhao; Kexi Qu; Man Li; Lin Zhao; Yuanyuan Wang; Zhenghua Hu; Qi Li

doi:10.1016/j.jplph.2025.154547

Dynamic changes of rice sheath non-structural carbohydrates and source-sink balance under elevated atmospheric CO₂ concentration and temperature stresses

J Plant Physiol. 2025 Jun 16:311:154547. doi: 10.1016/j.jplph.2025.154547. Online ahead of print.

Authors

Hao He¹, Jiabin Shi², Mingjie Chen³, Jing Zhao⁴, Kexi Qu⁵, Man Li⁶, Lin Zhao⁷, Yuanyuan Wang⁸, Zhenghua Hu⁹, Qi Li¹⁰

Affiliations

¹ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: 202311080003@nuist.edu.cn.
² Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: 202212080009@nuist.edu.cn.
³ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: 202312080037@nuist.edu.cn.
⁴ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: 202312070014@nuist.edu.cn.
⁵ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: 202312080040@nuist.edu.cn.
⁶ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: liman66622@163.com.
⁷ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: zhaolindeyx@126.com.
⁸ . School of Life Science, Huaiyin Normal University, Huaian, 223001, China. Electronic address: wyy@hytc.edu.cn.
⁹ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: zhhu@nuist.edu.cn.
¹⁰ Jiangsu Provincial University Key Laboratory of Agricultural and Ecological Meteorology, Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Ecology and Applied Meteorology, Nanjing University of Information Science & Technology, Nanjing, 210044, China. Electronic address: liqix123@sina.com.

PMID: 40527110
DOI: 10.1016/j.jplph.2025.154547

Abstract

Rising CO₂ levels and temperatures significantly affect rice yield and quality by altering key physiological processes. As vital carbon reserves, non-structural carbohydrates (NSC) maintain the source-sink balance, directly influencing grain filling and food security. This study simulated high CO₂ and temperature conditions using open-top chambers with four treatment groups: control (ACT, ambient CO₂ at 415 ppm and temperature), elevated CO₂ (EC, 600 ppm CO₂), elevated temperature (ET, ambient +2 °C), and combined CO₂ and temperature elevation (ECT, 600 ppm CO₂ +2 °C). NSC concentrations, along with key physiological indexes such as leaf nitrogen and antioxidant enzyme activity, and gene expression, was measured to assess climate impacts on japonica rice variety "Nanjing 9108" physiology and source-sink balance. This study found that EC enhanced NSC concentrations, increasing soluble sugars and starch by 6.33 % and 9.86 % at heading, raising stem sheath NSC by 9.30 %. Conversely, ET reduced sugars and starch by 16.67 % and 6.24 %, leading to a 7.75 % NSC decrease. Under ECT, NSC levels dropped by 1.07 %. Nitrogen concentrations in leaves, stem sheaths, and panicles declined under both EC and ET, EC reduced leaf nitrogen by 16.26 %, while ET lowered nitrogen in stem sheaths and panicles by 17.29 % and 16.53 %. EC upregulated OsSUT1 and OsSUT2 gene expression by 69.55 % and 131.85 %, boosting carbon transport, whereas ET suppressed those genes, reducing grain carbon supply. Overall, elevated CO₂ improves NSC accumulation and transport, enhancing yield potential, while elevated temperature hinders these processes. Managing NSC and nitrogen dynamics is crucial to ensure stable rice yields under climate change.

Keywords: Carbohydrate transport; Elevated CO(2); Japonica rice; Nitrogen allocation; Source-sink dynamics.