State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi, 712100, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
College of Life Sciences, Northwest A&F University, Yangling, Shaanxi, 712100, China.
Plant Physiol Biochem. 2020 Jul;152:243-251. doi: 10.1016/j.plaphy.2020.04.045. Epub 2020 May 7.
The stomata of maize (Zea mays) contain a pair of guard cells and a pair of subsidiary cells. To determine whether HO, Ca, and K in subsidiary cells were involved in stomatal movement, we treated four-week-old maize (Zhengdan 958) leaves with HO, diphenylene iodonium (DPI), CaCl, and LaCl. Changes in content and distribution of HO, Ca, and K during stomatal movement were observed. When exogenous HO was applied, Ca increased and K decreased in guard cells, while both ions increased in subsidiary cells, leading to stomatal closure. After DPI treatment, Ca decreased and K increased in guard cells, but both Ca and K decreased in subsidiary cells, resulting in open stomata. Exogenous CaCl increased HO and reduced K in guard cells, while significantly increasing them in subsidiary cells and causing stomatal closure. After LaCl treatment, HO decreased and K increased in guard cells, whereas both decreased in subsidiary cells and stomata became open. Results indicate that HO and Ca correlate positively with each other and with K in subsidiary cells during stomatal movement. Both HO and Ca in subsidiary cells promote an inflow of K, indirectly regulating stomatal closure.
玉米（Zea mays）的气孔包含一对保卫细胞和一对副卫细胞。为了确定副卫细胞中的 HO、Ca 和 K 是否参与气孔运动，我们用 HO、二苯基碘（DPI）、CaCl 和 LaCl 处理了四叶期的玉米（郑单 958）叶片。观察了气孔运动过程中 HO、Ca 和 K 的含量和分布变化。当施加外源 HO 时，Ca 在保卫细胞中增加，K 在保卫细胞中减少，而这两种离子在副卫细胞中都增加，导致气孔关闭。在用 DPI 处理后，Ca 在保卫细胞中减少，K 在保卫细胞中增加，但 Ca 和 K 在副卫细胞中都减少，导致气孔张开。外源性 CaCl 增加了 HO 并减少了保卫细胞中的 K，同时显著增加了副卫细胞中的 HO 和 K，导致气孔关闭。在用 LaCl 处理后，HO 在保卫细胞中减少，K 在保卫细胞中增加，而这两种离子在副卫细胞中都减少，导致气孔张开。结果表明，在气孔运动过程中，HO 和 Ca 与副卫细胞中的 K 呈正相关。副卫细胞中的 HO 和 Ca 都促进 K 的流入，间接调节气孔关闭。
