Regression coefficient (R 2), P -values
and type of regression model fit are shown. R 2is shown in bold when P ≤ 0.001 (***), P ≤ 0.01 (**),P ≤ 0.05 (*) and P ≤ 0.1 (+). Smes, total
mesophyll cell surface area exposed to intercellular air space per unit
of leaf surface area; Sc, chloroplast coverage of
Smes, gm, mesophyll conductance to
CO2 diffusion estimated by Ogee et al . (2018);
mesophyll cell wall thickness (MCW);
SDada, adaxial stomatal density; SDaba,
abaxial stomatal density; SR, stomatal ratio; Narea,
leaf N content expressed on area basis; stomatal conductance to water
vapor diffusion (gsw); VED, average vein-to-epidermis
distance; VEDada, vein-to-adaxial epidermis distance;
VEDaba, vein-to-adaxial epidermis distance; IVD,
interveinal distance; total VLA, vein length per unit leaf area;
BSCW, BS cell wall thickness; BSias, BS
exposed to intercellular air spaces; BS area ratio (calculated as (BS
area/ [BS area + Mesophyll area]).