Hg^(2+)对苜蓿叶片的毒害效应

The toxic effect of Hg ^( 2+) on alfalfa leaves

研究了Hg2 + 对苜蓿叶片的毒害效应。结果表明 :随着Hg2 + 浓度的增加和处理时间的延长 ,叶绿素含量下降 ,电导度上升 ;低Hg2 + 浓度及短时间处理 ,超氧阴离子自由基 (O·2 )和丙二醛 (MDA)含量增加 ,SOD、POD和CAT等保护酶活性升高 ,表明膜系统受到了伤害 ;高Hg2 +浓度及长时间处理 ,O·2 和MDA含量下降 ,SOD、POD和CAT等保护酶活性降低 ,表明细胞结构和功能受到了不可逆的伤害。

The toxic effect of Hg 2+on alfalfa leaves was studied. The results showed that the content of chlorophyll decreased and the conductivity increased with Hg 2+ concentration′s increase and the treated time′s prolongation. In low Hg 2+ concentration and short treated time, the content of superoxide free radical(O · 2and malondialdehyde(MDA) increased, the activity of protective enzyme such as SOD?POD and CAT increased too, which indicated that the membrane system had been damaged. However, in high Hg 2+ concentration and the treated time′s prolonged, the content of O · 2 and MDA decreased and the activity of protective enzyme such as SOD?POD and CAT decreased too, which indicated that the construction and function of cells had been suffered irreversible damage.