Cyperaceae representatives present peculiar microsporogenesis and microgametogenesis, which raises the question of how regular the sedge pollen is. In order to answer this question, preanthesis pollen grains of Cyperaceae individuals were analyzed under different tools such as light and transmission electron microscopy, which included cytochemistry and immunogold procedures. The results showed that maturing pollen in Cyperaceae presents some unusual endomembrane behaviors. Endoplasmic reticulum and dictyosomes are concerned in classic secretion pathways in vegetative cells, and possibly the late breakdown of degenerative microspores. However, cortical and concentric endoplasmic reticulum are also present and are possibly related to other functions aside the biosynthetic pathway. Unconventional secretion of large membrane‐bound bodies containing cell wall precursors was also observed and confirmed by immunogold. However, since these bodies most likely receive material from dictyosomes, as observed in silver nitrate reaction, the “unconventional” status of this secretion is debatable. Reports of the literature show that these unusual endomembrane formations are not exclusive of the sedge pollen, but little attention have been given to them so far. This could represent an opportunity to re‐examine our understanding on the endomembrane system in pollen cells in general.

中文翻译：

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莎草科和其他被子植物的花粉内膜系统是否存在异常的超微结构特征？

莎草科代表呈现出独特的小孢子发生和小配子发生，这就提出了莎草花粉的规律性问题。为了回答这个问题，在不同的工具下分析了莎草科个体的花前花粉粒，如光和透射电子显微镜，其中包括细胞化学和免疫金程序。结果表明，莎草科成熟花粉呈现出一些不寻常的内膜行为。内质网和 dictyosomes 与营养细胞中的经典分泌途径有关，并且可能与退化小孢子的晚期分解有关。然而，皮质和同心内质网也存在，并且可能与生物合成途径之外的其他功能有关。免疫金还观察到并证实了含有细胞壁前体的大膜结合体的非常规分泌。然而，由于这些身体最有可能从 dictyosomes 接收物质，如在硝酸银反应中所观察到的，这种分泌物的“非常规”状态是有争议的。文献报道表明，这些不寻常的内膜形成并不排除莎草花粉，但迄今为止很少有人关注它们。这可能代表了一个机会，可以重新审视我们对花粉细胞内膜系统的总体理解。文献报道表明，这些不寻常的内膜形成并不排除莎草花粉，但迄今为止很少有人关注它们。这可能代表了一个机会，可以重新审视我们对花粉细胞内膜系统的总体理解。文献报道表明，这些不寻常的内膜形成并不排除莎草花粉，但迄今为止很少有人关注它们。这可能代表了一个机会，可以重新审视我们对花粉细胞内膜系统的总体理解。