Saridis Pavlos, Georgiadou Xenia, Shtein Ilana, Pouris John, Panteris Emmanuel, Rhizopoulou Sophia, Constantinidis Theophanis, Giannoutsou Eleni, Adamakis Ioannis-Dimosthenis S
Section of Botany, Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece.
Section of Ecology and Systematics, Department of Biology, National and Kapodistrian University of Athens, 15784 Athens, Greece.
Plants (Basel). 2022 Dec 5;11(23):3377. doi: 10.3390/plants11233377.
A special feature found in Amaryllidaceae is that some guard cells of the neighboring stomata form a "connection strand" between their dorsal cell walls. In the present work, this strand was studied in terms of both its composition and its effect on the morphology and function of the stomata in L. leaves. The structure of stomata and their connection strand were studied by light and transmission electron microscopy. FM 4-64 and aniline blue staining and application of tannic acid were performed to detect cell membranes, callose, and pectins, respectively. A plasmolysis experiment was also performed. The composition of the connection strand was analyzed by fluorescence microscopy after immunostaining with several cell-wall-related antibodies, while pectinase treatment was applied to confirm the presence of pectins in the connection strand. To examine the effect of this connection on stomatal function, several morphological characteristics (width, length, size, pore aperture, stomatal distance, and cell size of the intermediate pavement cell) were studied. It is suggested that the connecting strand consists of cell wall material laid through the middle of the intermediate pavement cell adjoining the two stomata. These cell wall strands are mainly comprised of pectins, and crystalline cellulose and extensins were also present. Connected stomata do not open like the single stomata do, indicating that the connection strand could also affect stomatal function. This trait is common to other Amaryllidaceae representatives.
石蒜科植物的一个特殊特征是，相邻气孔的一些保卫细胞在其背细胞壁之间形成了一条“连接链”。在本研究中，对这条链的组成及其对百合叶片气孔形态和功能的影响进行了研究。通过光学显微镜和透射电子显微镜研究了气孔及其连接链的结构。分别进行了FM 4-64和苯胺蓝染色以及单宁酸处理，以检测细胞膜、胼胝质和果胶。还进行了质壁分离实验。在用几种与细胞壁相关的抗体进行免疫染色后，通过荧光显微镜分析连接链的组成，同时应用果胶酶处理来确认连接链中果胶的存在。为了研究这种连接对气孔功能的影响，研究了几个形态学特征（宽度、长度、大小、孔径、气孔间距以及中间叶肉细胞的细胞大小）。结果表明，连接链由穿过相邻两个气孔的中间叶肉细胞中部的细胞壁物质组成。这些细胞壁链主要由果胶组成，同时也存在结晶纤维素和伸展蛋白。相连的气孔不像单个气孔那样开放，这表明连接链也可能影响气孔功能。这一特征在其他石蒜科植物中也很常见。
