A perspective on optimal leaf stomatal conductance under CO2 and light co-limitations.

Highlights: [•] Optimal stomatal conductance under CO2-light co-limitation is analytically obtained. [•] It reconciles existing formulations based on single limitations to photosynthesis. [•] Model predictions are compared to known stomatal responses to micro-environment. [•] Marginal water use efficiency response to short- and long-term CO2 shifts are discussed. [ABSTRACT FROM AUTHOR]