花生根瘤菌的分离鉴定及对重金属的抗性研究

Peanut Rhizobia:Isolation,Identification,and Characterization of Resistance to Heavy Metals

为筛选对多种重金属具有较强抗性的根瘤菌,通过从重金属污染农田采集的花生根瘤中分离纯化,得到34株根瘤菌,对其进行系统进化分析并构建16S rRNA基因系统发育树,以及对重金属(Cu^(2+)、Ni^(2+)、Cr^(6+)、Zn^(2+))的抗性分析。结果显示,34株根瘤菌中有33株属于根瘤菌属(Rhizobium),1株属于中华根瘤菌属(Ensifer);对Cu^(2+)具有较强抗性的菌株为HG6、HG13、HM13、HM23、HM52,对Ni^(2+)具有较强抗性的菌株为HM13、HW23、HW45,对Cr^(6+)具有较强抗性的菌株为HM14、HM21、HM23、HW2,对Zn^(2+)的抗性较强的菌株为HG6、HM1、HM52、HW20;HG13对4种重金属均具有较好抗性。

To screen out the rhizobia with strong resistance to heavy metals,we isolated 34 strains of rhizobia from peanut nodules in the heavy metal-contaminated farmland.A phylogenetic tree was built for these strains based on the 16S rRNA gene sequences.Furthermore,the resistance of these strains to heavy metals(Cu^(2+),Ni^(2+),Cr^(6+),and Zn^(2+))was evaluated.The results showed that 33 out of the 34 strains belonged to Rhizobium and 1 strain belonged to Ensifer.Strains HG6,HG13,HM13,HM23,and HM52 demonstrated strong resistance to Cu^(2+).Strains HM13,HW23,and HW45 showed strong resistance to Ni^(2+).Strains HM14,HM21,HM23,and HW2 had strong resistance to Cr^(6+).Strains HG6,HM1,HM52,and HW20 showcased strong resistance to Zn^(2+).Strain HG13 had strong resistance to all the four heavy metals.