Fe concentration in the Fer-NAS-YSL2 lines (Masuda et al.2012). a; The Fe concentrations in T2 polished rice seeds (Oryza sativa cv. Tsukinohikari). Bars represent the Fe concentrations in polished seeds obtained from individual transgenic or non-transgenic plants. The numbers indicate the line numbers of the independent T1 lines. The arrows and numbers above the bars show the lines that contained high levels of Fe, which are shown in b for the subsequent generation. b; Fe concentrations in the T3 polished rice seeds (Oryza sativa cv. Tsukinohikari) harvested from the paddy field. ANOVA with the Tukey–Kramer HSD test was used for each four-block dataset (n = 4). The letters above the bars indicate significant differences (P < 0.05). NT, Non-transgenic rice; AN, OsActin1 promoter–HvNAS1 transgenic rice line No. 8 (Masuda et al. 2009); Fer-NAS-YSL2, transgenic rice lines that carry the OsGlb1 promoter–SoyferH2, OsGluB1 promoter–SoyferH2, OsSUT1 promoter–OsYSL2, OsGlb1 promoter–OsYSL2, and OsActin1 promoter–HvNAS1 (Masuda et al. 2012).