Speed of light-induced stomatal movement is not correlated to initial or final stomatal conductance in rice

• Published in: Photosynthetica Vol. 60; no. 3; pp. 350 - 359
• Main Authors: XIONG, Z., LUO, Q.W., XIONG, D.L., CUI, K.H., PENG, S.B., HUANG, J.L.
• Format: Journal Article
• Language: English
• Published: Academy of Sciences of the Czech Republic, Institute of Experimental Botany 01.01.2022
• Subjects: fluctuating light; gas exchange; intrinsic water-use efficiency; non-steady state; steady state
• ISSN: 0300-3604; 1573-9058
• DOI: 10.32615/ps.2022.013

In nature, plants are often confronted with wide variations in light intensity, which may cause a massive carbon loss and water waste. Here, we investigated the response of photosynthetic rate and stomatal conductance to fluctuating light among ten rice genotypes and their influence on plant acclimation and intrinsic water-use efficiency (WUEi). Significant differences were observed in photosynthetic induction and stomatal kinetics across rice genotypes. However, no significant correlation was observed between steady-state and non-steady-state gas exchange. Genotypes with a greater range of steady-state and faster response rate of the gas exchange showed stronger adaptability to fluctuating light. Higher stomatal conductance during the initial phase of induction had little effect on the photosynthetic rate but markedly decreased the plant WUEi. Clarification of the mechanism influencing the dynamic gas exchange and synchronization between photosynthesis and stomatal conductance under fluctuating light may contribute to the improvement of photosynthesis and water-use efficiency in the future.