水培条件下重金属Cr(Ⅵ)对作物种子萌发影响的试验研究

Experimental study on effects of hexavalent chromium on crop seed germination under solution culture

为保证再生水安全灌溉利用,通过试验研究了重金属Cr(Ⅵ)对4种典型作物种子发芽的影响。结果表明,Cr(Ⅵ)在低浓度(<1mg/L)时4种作物种子的各项发芽指标与对照均无显著性差异,随着浓度的增高则逐渐转变为抑制作用,浓度越高抑制作用越强。Cr(Ⅵ)对种子芽、根生长的影响远大于对发芽率的影响。对Cr(Ⅵ)浓度与芽长、根长及鲜重的抑制率进行相关分析,呈极显著正相关。通过计算EC25并比较发现,Cr(Ⅵ)对根生长的抑制作用大于对芽生长的抑制作用,4种作物根对Cr(Ⅵ)的敏感性强弱顺序为:西红柿>小麦>黄瓜>玉米。

In order to ensure the safe utilization of the reclaimed water for irrigation, some experiments on studying the influence of Cr（VI） on the seed germination of 4 kinds of typical crop seeds have been done. The results show that there is no significant difference in germination index among treatments at the low concentration （〈 1 mg/L） of Cr（Ⅵ）. With the increase of the concentration of Cr（Ⅵ）, the seed germination of the crop is significantly inhibited. The higher the concentration of Cr（Ⅵ） is, the stronger the inhibition is. In addition, the effect of Cr（Ⅵ） on the growth of crop sprouts and roots of the crop is stronger than that on the seed germination of the crop. There is strongly positive relationship between the concentration of Cr（Ⅵ） and the inhibition rate of crop sprout, root growth and fresh weight. The effect of inhibition on root growth is stronger than that on sprout. By computing and comparing EC25, the sensitivities to Cr（Ⅵ） of 4 typical crops is： tomato〉wheat〉cucumber〉maize.