PDF(Pubmed)
Abstract：
BACKGROUND: The Diplolepideae are the larger group within the Arthrodontae mosses, characterized by peristomes formed from residual cell walls. It is now understood that these peristomes exhibit diverse hygroscopic movements, playing a crucial role in spore release. However, the exact mechanism behind this movement remains unclear, lacking direct evidence. This study investigated the microscopic and submicroscopic structures of the peristomes in three Diplolepideae species: Hypopterygium fauriei (Besch.), Pylaisia levieri (Müll. Hal.) Arikawa and Regmatodon declinatus (Hook.) Brid. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to reveal the differences in their hygroscopic movement mechanisms.
RESULTS: The three species exhibited distinct responses upon wetting: H. fauriei\'s exostome closed inwards, P. levieri\' opened outwards, and R. declinatus\' elongated significantly. These differences are attributed to the varying microfibril deposition in the exostome layers. Uniform deposition in the inner layer and minimal deposition in the outer layer enabled exostome opening upon wetting and closing when dry. Our findings suggest that the diastole and contraction of fine microfibrils in the exostome plates and ridges are the key drivers of hygroscopic movement.
CONCLUSIONS: This study provides further evidence at both the structural and submicroscopic levels, contributing to the unraveling of the hygroscopic movement mechanism in Diplolepideae peristomes. This enhanced understanding sheds light on the relationship between peristome structure and function.
RESULTS: The three species exhibited distinct responses upon wetting: H. fauriei\'s exostome closed inwards, P. levieri\' opened outwards, and R. declinatus\' elongated significantly. These differences are attributed to the varying microfibril deposition in the exostome layers. Uniform deposition in the inner layer and minimal deposition in the outer layer enabled exostome opening upon wetting and closing when dry. Our findings suggest that the diastole and contraction of fine microfibrils in the exostome plates and ridges are the key drivers of hygroscopic movement.
CONCLUSIONS: This study provides further evidence at both the structural and submicroscopic levels, contributing to the unraveling of the hygroscopic movement mechanism in Diplolepideae peristomes. This enhanced understanding sheds light on the relationship between peristome structure and function.
摘要：
背景：Diplolepideae是Arthrodontae苔藓中较大的一组，其特征是由残余细胞壁形成的气孔。现在可以理解的是，这些气孔表现出不同的吸湿性运动，在孢子释放中起着至关重要的作用。然而,这场运动背后的确切机制尚不清楚，缺乏直接证据。这项研究调查了三种Diplolepideae物种的气孔周围的微观和亚微观结构：faurieihypopterymuumfauriei（Besch。),皮拉西亚·利维里（Müll。哈尔)有川和雷马托登declinatus(钩子。）布里德。使用扫描电子显微镜（SEM）和透射电子显微镜（TEM）来揭示它们的吸湿运动机制的差异。
结果：这三个物种在润湿时表现出不同的反应：福里氏H.P.levieri\'向外打开,和R.declinatus\'明显拉长。这些差异归因于外植体层中不同的微纤丝沉积。内层中的均匀沉积和外层中的最小沉积使得能够在润湿时打开并且在干燥时闭合。我们的发现表明，外植体板和脊中细小微原纤维的舒张和收缩是吸湿性运动的关键驱动因素。
结论：这项研究在结构和亚微观水平上提供了进一步的证据，有助于揭示Diplolepideae的吸湿运动机制。这种增强的理解揭示了perstome结构与功能之间的关系。
结果：这三个物种在润湿时表现出不同的反应：福里氏H.P.levieri\'向外打开,和R.declinatus\'明显拉长。这些差异归因于外植体层中不同的微纤丝沉积。内层中的均匀沉积和外层中的最小沉积使得能够在润湿时打开并且在干燥时闭合。我们的发现表明，外植体板和脊中细小微原纤维的舒张和收缩是吸湿性运动的关键驱动因素。
结论：这项研究在结构和亚微观水平上提供了进一步的证据，有助于揭示Diplolepideae的吸湿运动机制。这种增强的理解揭示了perstome结构与功能之间的关系。
