Disruption of ZmNRAMP2 reduces photosynthetic activity and plant growth under Mn deficiency. A and B, Dynamic changes of F_v/F_m in the youngest fully emerged leaf of zmnramp2-1 and WT (B73) (A), and zmnramp2-2 and WT (W22) (B) from 8 to 13 DAT. Maize seedlings were grown in nutrient solution supplied with 1-µM Mn (+Mn) or without Mn (−Mn). Data are presented as means ± sd (n = 6, biological replicates). C, Images of F_v/F_m in the youngest fully emerged leaf of zmnramp2-1 and WT (B73) at 13 DAT determined by PAM. D–F, Plant growth and dry weight of zmnramp2-1, zmnramp2-2, and the corresponding WT (B73, W22) plants grown under contrasted Mn regimes. D, Images of plant growth (scale bar = 25 cm), (E) shoot dry weight, and (F) root dry weight. Maize seedlings were grown in nutrient solution supplied with 1-µM Mn (+Mn) or without Mn (−Mn) for 14 days. Data are presented as means ± sd (n = 6, biological replicates). Significant difference was indicated at **P < 0.01 by Student’s t test.