What can mechanistic models tell us about guard cells, photosynthesis, and water use efficiency?. (February 2022)

• Record Type: Journal Article
• Authors: Blatt, Michael R.; Jezek, Mareike; Lew, Virgilio L.; Hills, Adrian
• Is Part Of: Trends in plant science. Volume 27:Number 2(2022)
• Page Start: 166
• Page End: 179
• Publication Date: 2022-02
• Subjects: Botany -- Periodicals; Botanique -- Périodiques; Botany; Periodicals; 580.5
• DOI: 10.1016/j.tplants.2021.08.010
• Languages: English
• ISSNs: 1360-1385

Abstract

Abstract : Stomatal pores facilitate gaseous exchange between the inner air spaces of the leaf and the atmosphere. The pores open to enable CO2 entry for photosynthesis and close to reduce transpirational water loss. How stomata respond to the environment has long attracted interest in modeling as a tool to understand the consequences for the plant and for the ecosystem. Models that focus on stomatal conductance for gas exchange make intuitive sense, but such models need also to connect with the mechanics of the guard cells that regulate pore aperture if we are to understand the 'decisions made' by stomata, their impacts on the plant and on the global environment. Highlights: Stomata are pores in the epidermis of plant leaves that facilitate gaseous exchange of water and atmospheric CO2, thereby connecting the water and carbon cycles of the world and exerting a major influence on both. Ecosystem models generally deal with stomata phenomenologically with respect to water availability, atmospheric humidity, CO2, and light but without connection to the physiology of the guard cells that regulate stomatal aperture. Guard cell physiology emerges as an important component missing from ecosystem models that will be essential to advance an understanding of the decisions 'made by' stomata in regulating the pore aperture. Guard cell models that capture the mechanics of guard cell transport and metabolism connect environmental inputs with stomatal behavior to accurately predict whole-plant gas exchange and photosynthetic carbon assimilation.