Figure 4.

Linear regression of the relationship among the carbon (δ¹³C), oxygen (δ¹⁸O), and hydrogen (δ²H) isotope compositions in mature kernels (grains) and in the DM and WSF of the flag leaves and the ears with the grain yield (GY), the stomatal conductance (g_s), and the total N concentration of the flag leaves (N-Flag) and ears (N-Ear). We measured the δ¹³C DM and δ¹³C WSF, δ¹⁸O WSF and δ²H WSF in 108 plots (five cultivars and four landraces, four growing conditions and three replicates per genotype and condition), whereas we measured δ¹⁸O DM and δ²H DM in 48 plots (two cultivars and two landraces, four growing conditions and three replicates) during the 2010 crop cycle. Analyses were performed in samples from the 2010 crop season. Level of significance: ***, P < 0.001.