Figure legends
Figure 1. Principal component analysis biplot showing major
axes of variation in important leaf-level physiological, structural and
anatomical traits among18 diverse C4 grasses.
Eigenvalues and factor loadings for first three principal components
(PCs) are shown in Supporting Information Table S4. The arrows are the
vectors showing the correlation (across the C4 grasses)
between a trait and the PCs. The position of species in PC space is
shown in blue circles. Points are mean values with n =3–6 per
species (Mean ± SE values are given in Pathare et al ., 2020 and
Table S2). Species names correspond to the description in Table S1.
Total VLA, vein length per unit leaf area; BSias, BS
exposed to intercellular air spaces; BSCW, BS cell wall
thickness; BS exposed to intercellular air spaces; BS area ratio
(calculated as (BS area/ [BS area + Mesophyll area]);
gm, mesophyll conductance to CO2diffusion estimated by Ogee et al . (2018); Anet,
net photosynthetic rates; Anet/E, instantaneous
water-use efficiency; SDada, adaxial stomatal density;
Smes, total mesophyll cell surface area exposed to
intercellular air space per unit of leaf surface area; SR, stomatal
ratio; gmax-ada, maximum stomatal conductance for
adaxial side; Narea, leaf N content expressed on area
basis; IVD, interveinal distance; VED, average vein-to-epidermis
distance; Kleaf, leaf hydraulic conductance.
Figure 2. Relationship of mesophyll conductance
(g m) with (a) interveinal distance (IVD), (b)
leaf thickness, (c) average vein-to-epidermis distance (VED) and leaf
hydraulic conductance (Kleaf) for the 18
C4 grasses measured in current study. Numbers correspond
to species listed in Table S1. Regression coefficient
(R 2) is shown when P ≤ 0.001 (***),P ≤ 0.01 (**), P ≤ 0.05 (*) and P ≤ 0.1 (+). Points
are mean values with n = 3-6 per species (Mean ± SE values are
given in Pathare et al ., 2020 and Table S2).
Figure 3. Relationship of net photosynthetic rates
(Anet) with (a) interveinal distance (IVD), (b) leaf
thickness, (c) average vein-to-epidermis distance (VED) and leaf
hydraulic conductance (Kleaf) for the 18
C4 grasses measured in current study. Numbers correspond
to species listed in Table S1. Regression coefficient
(R 2) is shown when P ≤ 0.001 (***),P ≤ 0.01 (**), P ≤ 0.05 (*) and P ≤ 0.1 (+). Points
are mean values with n = 3-6 per species (Mean ± SE values are
given in Pathare et al ., 2020 and Table S2).
Figure 4 . Relationship of leaf hydraulic conductance
(Kleaf) with (a) mesophyll surface area exposed to
intercellular air spaces (Smes), (b) ratio of adaxial to
abaxial stomatal density (SR) (c) adaxial stomatal density
(SDada), and (d) abaxial stomatal density
(SDaba) for the 18 C4 grasses. Numbers
correspond to species listed in Table S1. Regression coefficient
(R 2) is shown when P ≤ 0.001 (***),P ≤ 0.01 (**), P ≤ 0.05 (*) and P ≤ 0.1 (+). Points
are mean values with n = 3-6 per species (Mean ± SE values are
given in Pathare et al ., 2020 and Table S2).
Figure 5. Relationship of mesophyll conductance
(g m) and leaf hydraulic conductance with (a,c)
total maximum stomatal conductance to water vapor (gmax)
and (b, d) maximum stomatal conductance to water vapor for adaxial side
(gmax-ada) for the 18 C4 grasses
measured in current study. Numbers correspond to species listed in Table
S1. Regression coefficient (R 2) is shown whenP ≤ 0.001 (***), P ≤ 0.01 (**), P ≤ 0.05 (*) andP ≤ 0.1 (+). Points are mean values with n = 3-6 per
species (Mean ± SE values are given in Pathare et al ., 2020 and
Table S2).