重金属胁迫对任豆种子萌发及幼苗抗氧化酶活性的影响

为了解任豆幼苗的重金属耐性,探讨利用其进行重金属污染土壤修复的可行性,以尾矿、泥土及菌糠作为栽培基质的原料,在人工模拟重金属胁迫的条件下,对任豆种子进行了发芽试验,并测定了在不同重金属胁迫背景下任豆幼苗的SOD、POD和CAT活性.结果表明:任豆种子可以在含有重金属的栽培基质中萌发,但萌发率较低;在尾矿、泥土及菌糠3种原料适当比例混合的栽培基质中,任豆种子的萌发率相对较高;不同重金属对任豆幼苗抗氧化酶活性的影响不同,在低浓度的重金属离子胁迫下,任豆幼苗的SOD、POD和CAT活性均有不同程度升高,在高浓度的重金属离子胁迫下,其SOD、POD和CAT活性则逐渐降低;不同重金属对任豆幼苗抗氧化酶活性影响的大小排序为Cd2+>Cu2+>Pd2+>Zn2+.任豆幼苗对不同重金属有不同的耐性,其大小排序为:Zn2+>Pd2+>Cu2+>Cd2+.根据任豆幼苗的重金属耐性,可将其用于土壤重金属污染的植物修复,但土壤中的重金属含量应不超出其耐受的范围.

Effects of Heavy Metal Stress on Seed Germination and Seedlings Antioxidant Enzyme Activity of Zenia insigni

In order to understand the heavy metal tolerance of Zenia insigni seedlings ,to discuss the feasibility of heavy metal contaminated soil remediation with the seedlings .Tailing ,soil ,cultural residue of edible fungi was used as the raw material of cultivation substrate ,germination test of Z .insigni seeds were conducted un-der the condition of artificial simulation of the heavy metal stress ,the activities of SOD ,POD and CAT were determined by the authors .The results showed that although Z .insigni seeds could germinate in the cultiva-tion substrate containing heavy metals ,and the germination rate was low .But the germination rate of the seeds was relatively high ,when they were sown in mixed cultivation matrix which mixed with tailing ,cultural resi-due of edible fungi and soil with appropriate proportion .The effects of different heavy metals on antioxidant enzyme activities of Z .insignis seedlings were different .Under the stress of low concentration of heavy metal i-ons ,the activity of SOD ,POD ,CAT had certain degree increase .While ,under the stress of high concentration of heavy metal ions ,the activity of SOD ,POD ,CAT reduced gradually .The influences of different heavy met-als on antioxidant enzyme activities of Z .insignis seedlings were different ,the order were as follows :Cd2+ >Cu2+ >Pd2+ >Zn2+ I.t shown that Z .insignis seedlings had different heavy metal tolerance ,the order were as follows:Zn2+ >Pd2+ >Cu2+ >Cd2+ .Based on the tolerance of Z .insignis seedlings ,it might be considered to use as the tolerance plant in soil remediation of heavy metal pollution .But the heavy metal content in the soil should not exceed the range of its tolerance .