Facette, MichelleDacosta, MichelleMa, Li-JunBartlett, MadelaineSmith, LaurieLiu, Le2025-01-242025-01-242024-0910.7275/55389https://hdl.handle.net/20.500.14394/55389Stomata (singular “stoma”) are tiny pores found on the leaf surfaces of land plants that facilitate gas exchange. However, opening these stomatal pores also leads to water loss in plants. To balance water loss and carbon gain, the plants must regulate their stomatal opening and closure in response to external and internal cues. Stomata of the plant kingdom also exhibit a highly diversified morphology despite a common design of kidney-shaped guard cells. The number, shape, and size of subsidiary cells are also variable in stomata in the plant kingdom. Some species possess subsidiary cells, and some do not, so what is the contribution of the subsidiary cells to stomatal opening and closing? The speed of stomatal opening and closing reflects the ability of stomata to perceive and transduce external and internal signals, inducing turgor changes in guard and subsidiary cells. This response speed is a crucial parameter that defines water use efficiency, which is the ratio of carbon assimilation to water loss. The variation in stomatal opening and closing among species leads to differences in water use efficiency between species. Grass stomata, composed of a pair of dumbbell-shaped guard cells, surrounded by a pair of triangular-shaped subsidiary cells, are known to possess fast stomatal opening, and closing, what are the key factors that contribute to fast stomatal responses? In my thesis, I will analyze the contributions of specialized cells - subsidiary cells to stomatal opening and closing, and how the morphology of subsidiary cells varies in different genotypes of maize.Dissertation (Open Access)N/A