Fig. 3

Effects of altitude gradient on the activities of SOD (a), POD (b), APX (c), GR (d), DHAR (e) and MAHAR (f) in leaves of Herpetospermum pedunculosum (Ser.) Baill. The plant samples were selected from different altitude (2800 m, 3000 m, 3100 m and 3300 m), respectively. Different letters above bars indicate statistically significant differences between different altitudes at P < 0.05 according to Duncan’s multiple range Test. Significant differences P < 0.01 are indicated two asterisks