Responses of Leaf Anatomy and CO Concentrating Mechanisms of the Aquatic Plant to Variable CO.

Acclimation to variable CO was studied in floating leaves of the freshwater monocot grown in either low or high CO. The most striking anatomical variations responding to high CO included the enlarged upper epidermal cells and the decreased area of epidermal chloroplasts. Stomata that distributed on the upper surface, and the stomatic chamber area, showed no significant response to high CO.

Structural basis for C4 photosynthesis without Kranz anatomy in leaves of the submerged freshwater plant Ottelia alismoides.

Background And Aims: Ottelia alismoides (Hydrocharitaceae) is a freshwater macrophyte that, unusually, possesses three different CO2-concentrating mechanisms. Here we describe its leaf anatomy and chloroplast ultrastructure, how these are altered by CO2 concentration and how they may underlie C4 photosynthesis.

Methods: Light and transmission electron microscopy were used to study the anatomy of mature leaves of O.