Elevated CO₂ Alters the Physiological and Transcriptome Responses of <i>Pinus densiflora</i> to Long-Term CO₂ Exposure

• Published in: Plants
• Main Authors: Tae-Lim Kim, Hyemin Lim, Hoyong Chung, Karpagam Veerappan, Changyoung Oh
• Format: Article
• Language: English
• Published: MDPI AG 2022-12-01
• Subjects: carbon dioxide; climate change; open-top chamber; physiological response; transcriptome; <i>Pinus densiflora</i>
• Online Access: https://www.mdpi.com/2223-7747/11/24/3530
• ISSN: 2223-7747

Physiological response and transcriptome changes were observed to investigate the effects on the growth, metabolism and genetic changes of <i>Pinus densiflora</i> grown for a long time in an environment with an elevated atmospheric CO₂ concentration. Pine trees were grown at ambient (400 ppm) and elevated (560 ppm and 720 ppm) CO₂ concentrations for 10 years in open-top chambers. The content of nonstructural carbohydrates was significantly increased in elevated CO₂. It was notable that the contents of chlorophylls significantly decreased at an elevated CO₂. The activities of antioxidants were significantly increased at an elevated CO₂ concentration of 720 ppm. We analyzed the differences in the transcriptomes of <i>Pinus densiflora</i> at ambient and elevated CO₂ concentrations and elucidated the functions of the differentially expressed genes (DEGs). RNA-Seq analysis identified 2415 and 4462 DEGs between an ambient and elevated CO₂ concentrations of 560 ppm and 720 ppm, respectively. Genes related to glycolysis/gluconeogenesis and starch/sucrose metabolism were unchanged or decreased at an elevated CO₂ concentration of 560 ppm and tended to increase at an elevated CO₂ concentration of 720 ppm. It was confirmed that the expression levels of genes related to photosynthesis and antioxidants were increased at an elevated CO₂ concentration of 720 ppm.