Circadian Regulation Does Not Optimize Stomatal Behaviour
The circadian clock is a molecular timer of metabolism that affects the diurnal pattern of stomatal conductance ( ), amongst other processes, in a broad array of plant species. The function of circadian regulation remains unknown and here, we test whether circadian regulation helps to optimize diurn...
Gespeichert in:
Veröffentlicht in: | Plants (Basel) 2020-08, Vol.9 (9), p.1091 |
---|---|
Hauptverfasser: | , , , , , , , , , , |
Format: | Artikel |
Sprache: | eng |
Schlagworte: | |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | The circadian clock is a molecular timer of metabolism that affects the diurnal pattern of stomatal conductance (
), amongst other processes, in a broad array of plant species. The function of circadian
regulation remains unknown and here, we test whether circadian regulation helps to optimize diurnal variations in stomatal conductance. We subjected bean (
) and cotton (
) canopies to fixed, continuous environmental conditions of photosynthetically active radiation, temperature, and vapour pressure deficit (free-running conditions) over 48 h. We modelled
variations in free-running conditions to test for two possible optimizations of stomatal behaviour under circadian regulation: (i) that stomata operate to maintain constant marginal water use efficiency; or (ii) that stomata maximize C net gain minus the costs or risks of hydraulic damage. We observed that both optimization models predicted
poorly under free-running conditions, indicating that circadian regulation does not directly lead to stomatal optimization. We also demonstrate that failure to account for circadian variation in
could potentially lead to biased parameter estimates during calibrations of stomatal models. More broadly, our results add to the emerging field of plant circadian ecology, where circadian controls may partially explain leaf-level patterns observed in the field. |
---|---|
ISSN: | 2223-7747 2223-7747 |
DOI: | 10.3390/plants9091091 |