Figure 6. Effects of salt stress on H₂O₂ accumulation in the IbNFU1-overexpressing sweetpotato plants.

(A) Accumulation of H₂O₂ in the leaves of salt-tolerant transgenic plants (L4, L5, L27 and L41) and wild-type plant (WT). A plant grown in a 19-cm diameter pot was irrigated with a 200 mL of 200 mM NaCl solution once every 2 days for 10 days. (B) The average intensity of DAB staining leaves after converting to 256 grey scale images. Data are presented as means ± SE (n = 3). * and ** indicate a significant difference from that of WT at P<0.05 and <0.01, respectively, by Student's t-test.