Fig. 8

AR numbers during hydroponic culture of poplar cuttings with different concentrations of supplemented H2O2. There were 15 plants for 1000 μM H2O2 treatment; while 30 plants for all other treatments. AR number was presented by mean value of each treatment. The multiple comparisons was performed under the significant level of P value equal to 0.05. The error bar represents standard deviation for each treatment