Effect of LaCl_3 Solutions With Two pH Treatment on Brassica campestris Seed Germination and Seedling Growth Under Simulated Acid Rain Stress

Taking‘Zheshuang 72'Brassica campestris as materials,the effect of LaCl3 solutions with two pH treatments on the seed germination and seedling growth of Brassica campestris were investigated under simulated acid rain stress(AR)of pH 3.5.The results showed that,under the LaCl3 treatment of pH 6.5,the positive effect were found in any of LaCl3 treatments.And B.campestris seed germination under 10mg/L LaCl3 treatment significantly improved compared with those in the single AR stress,and the seedling growth as well.However,under the LaCl3 treatment of pH 4.5,only the 1mg/L LaCl3 had positive effect,while 5mg/L and 10mg/L LaCl3 had negative effect.Compared with the control treatment,B.campestris had lower seed germination and seedling growth,high POD activities and high MDA contents,which may be the reason that the accumulation of La and high toxicity of La under the low pH conditions.Results suggested that it was necessary to select an appropriate doseage and pH to make LaCl3 treatment had a positive effect.