Increased CO2 and light intensity regulate growth and leaf gas exchange in tomato

• DOI: 10.1111/ppl.13015
• Publication Date: 2019-08-03T09:28:42Z
• Authors: Tonghua Pan; Yunlong Wang; Linghui Wang; Juanjuan Ding; Yanfei Cao; Gege Qin; Lulu Yan; Linjie Xi; Jing Zhang; Zhirong Zou
• Keywords: Light intensity; Water Use Efficiency; Carbon fixation; Specific leaf area; Photosynthetic efficiency; Photosynthetic capacity

Carbon dioxide concentration (CO2 ) and light intensity are known to play important roles in plant growth carbon assimilation. Nevertheless, the underlying physiological mechanisms have not yet been fully explored. Tomato seedlings (Solanum lycopersicum Mill. cv. Jingpeng No. 1) were exposed two levels of CO2 three effects on growth, leaf gas exchange water use efficiency investigated. Elevated increased promoted dry matter accumulation pigment together seedling health index. had no significant effect nitrogen content but did significantly upregulate Calvin cycle enzyme activity. Increased photosynthesis, both a leaf-area basis chlorophyll basis. also light-saturated maximum photosynthetic rate, apparent quantum carboxylation and, with intensity, it raised capacity. However, reduced transpiration consumption across different thus increasing leaf-level plant-level efficiency. Among range treatments imposed, combination (800 µmol mol-1 high (400 m-2 s-1 resulted optimal We conclude that worked synergistically promote capacity by upregulation concentration, activity, energy fixation. lowered hence usage.