MOSS STOMATA IN HIGHLY ELABORATED OEDIPODIUM (OEDIPODIACEAE) AND HIGHLY REDUCED EPHEMERUM (POTTIACEAE) SPOROPHYTES ARE REMARKABLY SIMILAR
MOSS STOMATA IN HIGHLY ELABORATED OEDIPODIUM (OEDIPODIACEAE) AND HIGHLY REDUCED EPHEMERUM (POTTIACEAE) SPOROPHYTES ARE REMARKABLY SIMILAR
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DOI：
10.3732/ajb.1300214
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发表时间：
2013-12-01
影响因子：
3
通讯作者：
Renzaglia, Karen S.
中科院分区：
文献类型：
--
作者：
Merced, Amelia;Renzaglia, Karen S.
研究目的：藓类植物是理解陆地植物气孔起源、分化和早期功能的核心。Oedipodium，第一个现存的真正的气孔的苔藓，有一个精心制作的胶囊与众多的长孔气孔;相反，减少和短命蜉蝣有几个圆孔气孔。在这里，我们提出了一个比较研究的孢子体解剖结构和超微结构的气孔在两个不同的藓类和它的影响气孔的多样性和functions.Methods：成熟的孢子体的两种藓类进行了研究，利用光，荧光，扫描和透射电子显微镜。果胶的免疫定位进行了Oedipodium使用的LM 19 antibody.Key results：Oedipodium胶囊有广泛的海绵组织沿着的突起，而蜉蝣有最小的气孔下腔。气孔的超微结构和壁的增厚高度相似。孢子体被角质层覆盖，角质层在保卫细胞上较厚，并沿孔壁沿着延伸。结论：这些藓类植物气孔的超微结构彼此相似，比维管植物的气孔变化小。解剖特征，如角质层，导水细胞，海绵组织与大面积的气体交换的存在下更显着的俄狄浦斯孢子体和支持气孔的作用，在气体交换和水运输在发展和成熟。这些特征在蜉蝣属的退化孢子体中被修改。蒴果的解剖结构加上气孔在蒴果上的唯一存在支持了苔藓中的气孔也可能促进孢子的干燥和传播的概念。
Premise of the study: Mosses are central in understanding the origin, diversification, and early function of stomata in land plants. Oedipodium, the first extant moss with true stomata, has an elaborated capsule with numerous long-pored stomata; in contrast, the reduced and short-lived Ephemerum has few round-pored stomata. Here we present a comparative study of sporophyte anatomy and ultrastructure of stomata in two divergent mosses and its implications for stomata diversity and function.Methods: Mature sporophytes of two moss species were studied using light, fluorescence,and scanning and transmission electron microscopy. Immunolocalization of pectin was conducted on Oedipodium using the LM19 antibody.Key results: Oedipodium capsules have extensive spongy tissue along the apophysis, whereas those of Ephemerum have minimal substomatal cavities. Stomatal ultrastructure and wall thickenings are highly similar. Sporophytes are covered by a cuticle that is thicker on guard cells and extends along walls surrounding the pore. Epicuticular waxes and pectin clog pores in old capsules.Conclusions: Ultrastructure of stomata in these mosses is similar to each other and less variable than that of tracheophytes. Anatomical features such as the presence of a cuticle, water-conducting cells, and spongy tissues with large areas for gas exchange are more pronounced in Oedipodium sporophytes and support the role of stomata in gas exchange and water transport during development and maturation. These features are modified in the reduced sporophytes of Ephemerum. Capsule anatomy coupled with the exclusive existence of stomata on capsules supports the concept that stomata in moss may also facilitate drying and dispersal of spores.