对氯苯酚胁迫下李氏禾的净化性能、生长状态及生理生化响应

Purification performance,growth status,and physiological and biochemical responses of Leersia hexandra Swartz under 4-chlorophenol stress

研究不同浓度(0、1、5、10、25、50和75 mg/L)李氏禾(Leersia hexandra Swartz)在对氯苯酚(4-chloro phenol,4-CP)污染水体的净化效果及植物的生长状态和生理生化响应,揭示该植物对4-CP胁迫的耐受性等特性.结果显示:李氏禾对污水中的4-CP具有较好的净化去除作用,在大于10 mg/L 4-CP浓度下去除率有所下降但仍可达95%以上.低浓度(<5 mg/L)4-CP胁迫能够促进李氏禾生长,而高浓度(>5 mg/L)胁迫对植物生长具有明显的抑制作用.随着4-CP浓度增加,叶组织中可溶性蛋白含量下降至8.23 mg/g,丙二醛(MDA)和过氧化氢(H_(2)O_(2))含量显著升高,分别升高到6.03 nmol/mg(prot)、31.1 mmol/mg(prot),超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性分别先升到66.45 U/mg(prot)、25.33 U/mg(prot)后降至51.92 U/mg(prot)、17.68 U/mg(prot),过氧化物酶(POD)活性上升,达到55.80 U/mg(prot).上述结果表明李氏禾对4-CP胁迫具有一定的耐受性和净化作用,可作为4-CP污染水体的一种潜在可利用修复植物,结果可为后续采用植物修复方法治理酚类污染水体的研究提供依据.(图6参42)

The purification effect of Leersia hexandra Swartz on water body stress at different concentrations(0,1,5,10,25,50,and 75 mg/L)of 4-chlorophenol(4-CP)pollution,as well as the growth status and physiological and biochemical responses of the plants were investigated to determine the tolerance and metabolic characteristics of L.hexandra under 4-CP stress.The results showed that L.hexandra had an effective purification and removal effect on 4-CP in sewage,and the removal rate of 4-CP dropped at concentrations greater than 10 mg/L,but could still reach more than 95%.Low concentrations(<5 mg/L)of stress promoted the growth of L.hexandra.In contrast,high-stress concentrations(>5 mg/L)had an inhibitory effect on plant growth.With the increase in 4-CP concentration,the soluble protein content in leaf tissues decreased to 8.23 mg/g and the levels of malondialdehyde and H_(2)O_(2) increased significantly to 6.03 nmol/mg prot and 31.1 mmol/mg prot respectively,and the activities of superoxide dismutase and catalase first increased to 66.45 U/mg prot and 25.33 U/mg prot and then decreased to 51.92 U/mg prot and 17.68 U/mg prot,respectively.Peroxidase activity increased to 55.80 U/mg prot.This study indicates that L.hexandra has a certain tolerance and purification effect under 4-CP stress and can be used as a potential phytoremediator for water bodies polluted by 4-CP.These results also provide a basis for follow-up studies on the treatment of phenolic-polluted water using phytoremediation.