Y(I) (A and D), Y(ND) (B and E), and Y(NA) (C and F) in wild-type N. tabacum (black circles) and three transgenic lines (B7, white circle; RI9, white triangle; and RI29, white square) with altered AOX amount, in both well-watered plants (A–C) and moderate drought-stressed plants (D–F). Data are the mean ± se of three independent experiments.