Abstract: 【Objective】To explore the effect of canola water extract on the growth of the seedlings.【Methods】Using distilled water as the control,three concentrations（0.025,0.050,and 0.100 g/mL）of laboratory prepared canola water extract were set to analyze the effects on canola seed germination,seedling growth,main nutrients,and defense enzyme activity.【Results】Compared with the control,the canola water extract of 0.050 g/mL and 0.100 g/mL significantly（P<0.05）reduced the seed germination rate of canola. At the concentration of 0.025 g/mL there were promotion effects on stem length,while at concentrations of 0.050 and 0.100 g/mL,there were inhibitory effects on stem length. All three concentrations had inhibitory effects on the root length of canola seedlings. As the concentration of canola water extract increased,the allelopathic comprehensive effects of canola were "low promotion and high inhibition". In comparison with the control,concentration of 0.100 g/mL significantly（P<0.05）reduced the canola protein content. At concentration of 0.050 g/mL canola proline content was 115.39% higher than the control. The SOD activity of canola treated with different concentrations of water extract was significantly（P<0.05）lower than the control. At the concentration of 0.025 g/mL,the POD activity of canola seedlings was significantly（P<0.05）higher than the control. Different concentrations of water extract treatment had different effect on the variations in canola malondialdehyde content.【Conclusion】Strong autotoxicity existed in canola.

Key words: Canola, Water extract, Autotoxicity