Effects Of Cd And Sewage Combined Pollution On Corn Seedling Metabolite Based On The GC-MS Technology

In order to research the effect of heavy metal Cd and wastewater combined pollution on com seedling,this paper study the effects of Cd Single and combined pollution?Cd and sewage irrigation?on growth,enzyme activity and metabolite changes of corn seedlings,using a variety of instrumental analysis methods and GC-MS metabolomics technology.The main results are as follows:1.Compared with CK,the low concentration of Cd²⁺?1?10 mg/L?improve the corn seed germination rate;the high concentration?10?50 mg/L?of Cd²⁺ have an obvious inhibitory effect on plant height and root length.2.Cd²⁺ can increase four antioxidant enzyme activity of corm seedling in all treatments and the activity increased with concentration of Cd²⁺ increasing.The effect of wastewater to the increase of SOD CAT and GST induced by Cd²⁺ is different around the concentration of Cd²⁺ at 10 mg/L.Compared with Cd single treatment,enzymes activity are lower in combined pollution in low concentration of Cd²⁺?1?10 mg/L?;and enzymes activity are higher in high concentration of Cd²⁺?10?50 mg/L?.The results show that the concentration of Cd²⁺ at 10 mg/L is a sensitive point of sewage effecting the three kinds of enzymes activity induced by Cd²⁺.And the concentration of Cd²⁺ at 5 mg/L is a sensitive point of sewage effecting the POD enzyme activity.3.Using GC-MS and AMDIS software,the research study corn seedling metabolite species identification,quantitative analysis and PCA analysis in different treatments,the results are as follows:?1?The research identifies 49 kinds of corn seedling metabolites in different treamentss,the metabolites include four categories?amino acids,sugars,organic acids,and other?.?2?The content of corn seedling metabolites is different in different treatments.And the content difference is resulted to the different concentration of Cd²⁺.Compared with their respective blank controls,in Cd single pollution treatment,Cd²⁺ induces the content rising of six kinds of amino acid;the reducing of most sugar metabolites;the reducing of lactic acid,phenol and malic acid,the reducing of benzoic acid and rosemary acid at the higher concentration of Cd²⁺;and the reducing of triethanolamine and mannitol.Cd and sewage combined pollution lead to the content rising of four categories metabolites,but the significant degree is different.?3?Compound pollution compared with single pollution,the PCA results show,Most of the treatments are different from others,when the concentration of Cd²⁺ at 10 mg/L,compound pollution and single pollution have litter difference.When the concentration of Cd²⁺ is the same,compared with the single pollution,the content of corn seedling metabolite in combined pollution treatment is significant effected.The effect of sewage to the induction of Cd²⁺ is different with different concentration,with the exception of glucose showing enhancement function in all combined pollution treatments,when the concentration of Cd²⁺ is higher??10 mg/L?,sewage enhances the induction of Cd²⁺ to amino acids metabolite and some organic acids metabolite,and when the concentration of Cd²⁺ is lower?<10 mg/L?,sewage mitigates the induction of Cd²⁺ to most of the metabolite in corn seedling.In conclusion,the concentration of Cd²⁺ at 10 mg/L is a sensitive point to influence corn seedling growth,many indicators have different changes before and after the concentration.The relationship between human body health and the combined pollution of high concentration of Cd²⁺ and sewage should cause high attention,and it is worth further research.