重金属对莴苣种子萌发和幼苗生长的抑制效应

Inhibition Effect of Heavy Metal on Seed Germination and Seedling Growth of Lettuce

以莴苣种子为试材,采用水培方法,研究了重金属元素铜(Cu)、铬(Cr)、铅(Pb)对莴苣种子萌发、幼苗生长的影响。结果表明:Cu2+、Pb2+在低浓度(≤50mg/L)下与对照组相比,对莴苣种子萌发影响无显著差异(P>0.05),随着浓度的增高则逐渐转变为抑制作用,Gr6+对莴苣种子萌发有明显的抑制作用;Cu2+、Gr6+、Pb2+对幼苗生长均呈现抑制作用,且浓度越高,抑制作用越明显,3种重金属溶液处理对莴苣幼苗根的抑制率都要明显大于对芽的抑制率(P<0.05);莴苣种子根对3种重金属的敏感度强弱顺序为:KCr2O3>Pb(NO3)2>CuSO4。

Taking lettuce as material, by hydroponic experiments,the effect of heavy metal elements Cu,Cr and Pb on seed germination and seedling growth were studied. The results showed that there was no significant difference （P〉0. 05） in germination index among treatments at the low concentration （450 mg/L） of Cu,Pb solution. The inhibitory effect of Cr solution was the most obvious,and with the increase of the concentration,the inhibition had risen sharply. The inhibitory effect of the three kinds of heavy metal solution on lettuce seedlings root were significantly greater than bud. The seedling root length and the shoot length were decreased, with the increase of salt concentration of heavy metals. And the toxicity of three kinds of heavy metal salts was KCr2O3〉Pb（NO3 ）2 〉CuSO4.