《生命科学》 2022, 34(4): 448-458
水稻作为亚洲主要口粮作物，生产中常遭受水分亏缺的影响，进而导致光合速率和产量显著降低。干旱条件下，气孔导度(gs) 和叶肉导度(gm) 是限制光合速率的主要因素。gs 表征CO2 从叶片周围的大气通过气孔移动到气孔下的内腔的传导阻力，gm 用于衡量细胞间隙CO2 通过叶肉到达叶绿体基质内的核酮糖-1，5- 二磷酸羧化酶/ 加氧酶(RuBisCo) 羧化部位的传导阻力。该文从gs 和gm 对干旱胁迫的响应入手，系统总结了气孔大小(S)、气孔密度(D)、脱落酸(ABA)、水通道蛋白(AQPs) 等对gs 的调控机理，以及单位叶面积暴露于细胞间隙的叶绿体表面积 (Sc/S )、细胞壁厚度(Tcw )、碳酸酐酶(CAs) 和AQPs 等对gm 的调控机制。在此基础上，阐述了gs 和gm 二者响应干旱的协同作用机理，提出了生理层面和叶片结构层面协同调控水稻叶片gs 和gm 的假设。最后对干旱条件下栽培措施提高光合性能的相关研究进行了展望。该文将对水稻抗旱丰产高效的品种选育和栽培措施提供一定的理论依据和实践指导。
通讯作者：何海兵 , Email:firstname.lastname@example.org
Rice (Oryza sativa L.), as a major food crop in Asia, is often affected by water deficit, which leads to a significant decrease in photosynthetic rate and yield. Stomatal conductance (gs) and mesophyll conductance (gm) are the main factors limiting photosynthesis under drought conditions. gs characterizes the conduction resistance of CO2 moving from the atmosphere around the leaf through the stomata to the inner cavity under the stomata, while gm is used to measure the conduction resistance of intercellular CO2 through the mesophyll to the carboxylation site of RuBisCo in the chloroplast matrix. Starting with the response of gs and gm to drought stress, this paper systematically summarized the regulation mechanism of stomatal size (S), stomatal density (D), abscisic acid (ABA) and aquaporins (AQPs) on gs, as well as the regulation mechanism of gm by the chloroplast surface area exposed to intercellular airspaces per leaf area (Sc/S), cell wall thickness (Tcw), carbonic anhydrases (CAs) and AQPs. Based on these above, this article expounds the synergistic mechanism of gs and gm in response to drought, assumes the synergistic regulation of gs and gm in rice leaves at physiological level and leaf structure level. Finally, the related research on cultivation measures to improve photosynthetic performance under drought conditions was prospected. This paper will provide some theoretical basis and practical guidance for the breeding and cultivation measures of rice varieties with drought resistance, high yield and high efficiency.
Communication Author：HE Hai-Bing , Email:email@example.com