Effects of habitat MAP and MAT on leaf-level traits of C4 grasses
We investigated the relationship of leaf-level traits, affecting gm and Kleaf and hence photosynthetic C-gain and transpirational water-loss respectively, with two main habitat climate variables- mean annual temperature (MAT) and mean annual precipitation (MAP). Anatomical traits associated with gm and Kleaf that were measured in current study are shown in Fig. S1. Mean values along with SE for the leaf-level traits measured in the current study are given in Table S2 and Pathare et al ., 2020. Mean values along with SE for MAP and MAT are shown in Fig. S9. None of the measured photosynthetic C-gain or transpirational water-loss traits measured in current study related with MAT (Table 1). However, MAP showed a significant relationship with many important leaf-level traits associated with photosynthetic C-gain or transpirational water-loss (Table 1, Fig. S5, S6 and S7). Specifically, there was a significant negative relationship between MAP and Smes (R 2 = -0.50, P< 0.01), Sc (R 2 = -0.60, P < 0.001), SDada(R 2 = -0.20, P = 0.06), SR (R 2 = -0.21, P = 0.05), gmax (R 2 = -0.24, P = 0.04), gmax-ada (R 2 = -0.43,P = 0.003), Narea (R 2 = -0.21, P = 0.05), leaf thickness (R 2 = -0.35, P = 0.037), average VED (R 2 = -0.45, P = 0.01), VEDada(R 2 = -0.45, P = 0.01) and BSCW (R 2 = -0.39, P = 0.021). Whereas, there was a significant positive relationship between BSias and MAP (R 2 = 0.27,P = 0.026). We also investigated the relationship of functional traits like gm and gsw with MAP for the 18 C4 grasses. There was no significant relationship between gsw and MAP (Table 1). However, there was a strong negative relationship between gm and MAP (R 2 = -0.43, P = 0.015), whereas Kleaf showed a marginally significant positive relationship with MAP (R 2 = 0.20, P = 0.07, Table 1).