Forms, Formation and Functions of the Stomata and Stomatal Complex

Stoma refers to the pore and the surrounding guard cells. A stomatal complex includes the guard cells and neighboring subsidiary cells. Subsidiary cells facilitate guard cell movements by offering a mechanical advantage. Subsidiary cells are related to certain morphologies of stomatal complex (e.g., sunken stomata) that affect gas (CO₂, H₂O, and O₂) exchange. Guard cells and subsidiary cells may originate from a single cell lineage, or subsidiary cells may be recruited from cells adjacent to the guard mother cell. The morphology and function of subsidiary cells vary from species to species.
Botanists have long been intrigued by the relationship between structure and function in stomatal apparatus. As the architecture of stomatal complex is so important for its behavior, it is pertinent to inquire into its structure and the mechanisms that govern its formation. A comprehensive understanding of the structure and development of stomatal complex can promote the interpretation of stomatal complex function. Furthermore, stomatal complexes are useful as model systems for the study of cell shaping (guard cells) and the cooperative interaction between adjacent cells (subsidiary cells) during cell development.
The molecular mechanisms of stomatal development have been revealed in the model plant Arabidopsis thaliana and recently in grasses. The development of stomatal complexes in grasses differs from stomatal development in Arabidopsis thaliana, as grass stomata are formed from dumbbell-shaped guard cells that are flanked by subsidiary cells that develop in parallel rows within defined and specific epidermal cell files. A diverse range of stomatal patterning has been found in different major groups of plants. Therefore, more details regarding the common and different mechanisms of formation of stomata and stomatal complex in diverse plants remain to be unraveled.

The goal of this Research Topic is to collect papers regarding stomatal structure and development, and the morphologies and function of the stomatal complex. We welcome articles about the molecular mechanisms of stomatal development and formation of stomatal complex in model and non-model plants. We also welcome articles discussing the morphologies and function of stomata and stomatal complex in diverse plants. We wish to highlight the diversity in structure and formation of stomata and stomatal complexes, and the functional relevance.

In this Research Topic, we welcome all article types published by Frontiers in Plant Science. Authors are invited to submit manuscripts on the following subthemes but are not limited to:
• Molecular mechanisms of stomatal development in model and non-model plants
• Morphological structures and function of stomatal complex
• Structural diversity of stomata and stomatal complex
• Formation and function of sunken stomata in plants
• Interactions of stomata and stomatal complex with pathogens
• Function of stomata and stomatal complex in abiotic stresses
• Stomata and stomatal complex in ecology and evolution
• Stomata and stomatal complex under a changing climate

Keywords: stomatal complex, subsidiary cells, stomatal encryption, xeromorphy, Florin rings, Stomata, Guard cells, Stomatal development, Stomatal movement

Important note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.