生物炭对铜胁迫下红壤地油菜苗期叶绿素和保护性酶活性的影响

Effects of biochar on chlorophyll and protective enzyme activity of rape seedlings in red soil under copper stress

通过盆栽试验,研究了不同生物炭添加量(质量分数为0、2%、5%)对铜胁迫(300 mg·kg^(-1))下红壤地油菜(Brassica campestris L.)苗期叶绿素含量、抗氧化酶活性[超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和过氧化物酶(POD)]、可溶性蛋白含量及丙二醛含量(MDA)的影响。结果表明:铜胁迫下油菜叶片的叶绿素a、b和总叶绿素含量均有所降低,SOD、CAT、POD、MDA及可溶性蛋白含量均增加;随着生物炭添加量的增加,油菜叶片的叶绿素a、b及总叶绿素含量呈上升趋势,油菜叶片的SOD、CAT、POD、MDA及可溶性蛋白含量则均呈一定的下降趋势。综合来看,施加生物炭有利于提高红壤地铜污染(300 mg·kg^(-1))中油菜苗期的叶绿素含量,减缓铜胁迫的毒害作用,从而有利于维持油菜正常生长。

A pot experiment was carried out to study the effects of biochar additions on chlorophyll content, antioxidant enzyme activity[superoxide dismutase（SOD）, catalase（CAT）, and peroxidase（POD）], soluble protein content and malondialdehyde（MDA） content in rape（Brassica campestris L.）seedlings in red soil under copper stress（300 mg·kg-1）. The biochar was applied at 0, 2%, and 5%（m/m）. Copper stress decreased content of chlorophyll a and b and total chlorophyll, but increased SOD, CAT, POD, MDA, and soluble protein content in rape leaves. Compared with no biochar addition, applying biochar increased the content of chlorophyll a and b and total chlorophyll, but reduced the activities of SOD, CAT, POD, and MDA, and the content of soluble protein in rape leaves. In conclusion, biochar applications improve chlorophyll content of rape seedlings, alleviate copper stress on rape seedlings, and maintain rape seedling normal growth under 300 mg Cu·kg--1 stress.