铅胁迫对黄瓜幼苗根系生长和内源激素含量的影响

Effect of Lead Pollution on Root Growth and Endogenous Hormone Content of Cucumber Seedlings

对水培条件下的黄瓜幼苗进行不同浓度的铅处理,探讨了铅胁迫对黄瓜幼苗根系生长的影响及4种内源激素含量的变化趋势。结果表明,低浓度铅胁迫条件下(100 mg/L)对黄瓜幼苗根系早期生长有促进作用,铅浓度越高,对黄瓜幼苗根系生长的抑制作用越强。主根长度随铅浓度的增大而减小,但在100 mg/L浓度铅胁迫下最长,而铅胁迫对幼苗根系的侧根形成没有太大的影响。4种内源激素变化表现为:随铅浓度的增加,IAA含量先上升后下降,Z(玉米素)的含量呈下降趋势,ABA的含量一直上升,对GA3含量的变化似乎没有太大影响,但是所有铅处理的GA3含量均高于对照。

In a solution--culture experiment, cucumber seedlings were treated with different concentrations of lead, so as to investigate the influence of Pb^2＋ stress on the root growth and four endogenous hormones of cucumber seedlings. The result showed that the growth of cucumber seedlings was promoted by lower concentrations of lead （100mg/L）. The higher the lead con- tent, the stronger the growth inhibition on cucumber seedlings. The changing trends of four endogenous hormones were as follows： IAA increased first and then decreased, Z content declined continously, ABA content raised all the time, and GA3 content was not significantly affected though all the treatments were higher than the control.