The activities of superoxide dismutase (SOD) (A), ascorbate peroxidase (APX) (B), glutathione reductase (GR) (C), and catalase (CAT) (D) and the contents of ascorbate (AsA) (E) and reduced glutathione (GSH) (G) and the ratios of AsA/dehydroascorbate (DHA) (F) and GSH/oxidized glutathione (GSSG) (H) in the second leaves. Rice seedlings were grown under K-sufficient (control) and -deficient (−K) conditions for 12 days. The second leaves were then used to determine the contents of AsA, DHA, GSH, and GSSG. Bars indicate standard errors (n = 4). Asterisks represent values that are significantly different between control and − K treatments at P < 0.05.