Comparative Metabolomics Analysis Of Dongnongdongmai 1 Response To Low Temperature Stress

Metabolomics analysis is one of the most effective methods for the analysis of metabolites in biological individuals.In this study,the current advanced GC-TOF/MS detection technique was used to investigate the metabolic changes of winter wheat Dongnongdongmai 1 under low temperature.The metabolites in the tiller nodes at 5?,-10? and-25? of Dongnongdongmai 1 under field condition were determined.The main metabolites were selected according to the data dimension reduction results obtained by SIMCA software.It can initially show us that winter wheat Dongnongdongmai 1 adapt to low temperature metabolic regulation mechanism was through the identification of metabolites.In order to make the identification results more convincing,we identified the representative metabolites detected by GC-TOF/MS for biological validation,mainly refer to the temperature comparison results,selected key metabolites in the significant metabolic pathway,And the real-time quantitative method was used to analyze the genes of the corresponding regulatory enzymes.(1)The metabolomics database of the tiller nodes of Dongnongdongmai at 5?,-10? and 25? was established.A total of 419 non-target metabolites were obtained from the result of the comparison of different temperature databases,among which 81 were significant metabolites.Based on the HMDB database,the metabolites were classified and analyzed by the comparison of different metabolites at different temperatures.The metabolic processes such as sugars,amino acids,nitrogen,organic acids and nucleic acids were obtained.(2)After the advent of low temperature,the relative content of Val increased with the decrease of temperature,such as Pro and so on.The osmotic adjustment of winter wheat was enhanced at low temperature,while the contents of Asp and other minor amino acids decreased with the decrease of temperature,and participate in the metabolic cycle of some low temperature adaptation.(3)Carbohydrate metabolism was significantly enhanced in low temperature adaptation,and most of the sugar contents increased with decreasing temperature,including sorbitol,sugar,honey two threitol induced by low temperature,the soluble carbohydrate increased the osmotic adjustment ability of winter wheat.(4)With the temperature decreased,nitrogen metabolism also showed a significant change.With the decrease of temperature,the relative content of spermidine decreased first and then increased slightly,while the relative content of urea and two amide was obviously increased after low temperature induction.These changes in nitrogen adapted to the growth of winter wheat under low temperature.(5)Organic acids also changed greatly in the process of temperature change,but most organic acids are intermediate metabolites,so it is difficult to determine their specific role in cold resistance.(6)The nucleotides were rarely detected in this experiment(only 4 related compounds were detected),and there are few current relevant literatures,so it is necessary to carry out more targeted detection and analysis.(7)qRT-PCR was used to detect the expression of key enzymes in sucrose metabolism,inositol metabolism and metabolism.It was found that with the temperature decreased,the trend of up-regulation(TaSuS?TaSPS?TaMIPS and TaOASTL)or down-regulation(TaIMP and TdSAT)was observed at different temperature nodes to adjust the corresponding enzyme content.The expression change of these genes was consistent with the results of metabonomics analysis,indicating that metabolomics analysis has application value in the study on Cold Resistance of Winter Wheat.In summary,GC-TOF/MS was used to detect the metabolic changes of winter wheat Dongnong-dongmai 1 at low temperature,which could reflect the change network of winter wheat adapted to low temperature after the advent of low temperature.