Stem anatomy in monocotyledonous aquatic and wetland plants

Abstract

In this chapter, we present characteristic anatomical structures of a large number of monocotyledonous aquatic and wetland species, 66% of which are graminoids (117 species), and try to relate microscopic features to hydrological conditions and taxonomic origin. The study is based on cross sections of culms. Each section is located at an internode above the leaf sheaths, approximately in the center of the total length of the culms. Since anatomical variation is minimized by the constant internal location of the section within the culm, the whole set of analyzed material is comparable. Double staining gives additional information about the distribution of lignified and unlignified parts. We focus on two anatomical features: the presence of fibers and different aerenchyma tissue types as related to mechanical support and aeration.