Stomatal conductance reduction tradeoffs in maize leaves: A theoretical study.
Plant Cell Environ
; 47(5): 1716-1731, 2024 May.
Article
en En
| MEDLINE
| ID: mdl-38305579
ABSTRACT
As the leading global grain crop, maize significantly impacts agricultural water usage. Presently, photosynthesis ( A net ${A}_{\text{net}}$ ) in leaves of modern maize crops is saturated with CO 2 ${\text{CO}}_{2}$ , implying that reducing stomatal conductance ( g s ${g}_{{\rm{s}}}$ ) would not affect A net ${A}_{\text{net}}$ but reduce transpiration ( τ $\tau $ ), thereby increasing water use efficiency (WUE). While g s ${g}_{{\rm{s}}}$ reduction benefits upper canopy leaves under optimal conditions, the tradeoffs in low light and nitrogen-deficient leaves under nonoptimal microenvironments remain unexplored. Moreover, g s ${g}_{{\rm{s}}}$ reduction increases leaf temperature ( T leaf ${T}_{\text{leaf}}$ ) and water vapor pressure deficit, partially counteracting transpiratory water savings. Therefore, the overall impact of g s ${g}_{{\rm{s}}}$ reduction on water savings remains unclear. Here, we use a process-based leaf model to investigate the benefits of reduced g s ${g}_{{\rm{s}}}$ in maize leaves under different microenvironments. Our findings show that increases in T leaf ${T}_{\text{leaf}}$ due to g s ${g}_{{\rm{s}}}$ reduction can diminish WUE gains by up to 20%. However, g s ${g}_{{\rm{s}}}$ reduction still results in beneficial WUE tradeoffs, where a 29% decrease in g s ${g}_{{\rm{s}}}$ in upper canopy leaves results in a 28% WUE gain without loss in A net ${A}_{\text{net}}$ . Lower canopy leaves exhibit superior tradeoffs in g s ${g}_{{\rm{s}}}$ reduction with 178% gains in WUE without loss in A net ${A}_{\text{net}}$ . Our simulations show that these WUE benefits are resilient to climate change.
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Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Hojas de la Planta
/
Zea mays
Tipo de estudio:
Prognostic_studies
Idioma:
En
Año:
2024
Tipo del documento:
Article