3.2 Difference in structure-function relationships between roots and branches
t 2/b 2 and |P 50| were positively correlated both in branches (r 2 = 0.50,P < 0.001; Figure 2a) and in roots (r 2 = 0.60, P < 0.001; Figure 2b). By contrast, there were significantly negative correlations betweenD h and |P 50| both in branches (r 2 = 0.50, P < 0.001; Figure 2c) and in roots (r 2 = 0.31, P< 0.001; Figure 2d), whereas the regression coefficient of root and branch traits had no significant differences (P = 0.424).