Integrated proteomics and metabolomics for dissecting the mechanism of global responses to salt and alkali stress in Suaeda corniculata

Soil alkalinity and salinity are two of the most common environmental stress factors that impact plant growth and productivity. S. corniculata is native to the saline-alkali soil of Northeast China which shows a higher alkali tolerance than other suaeda plants. It will be very important to identify the effect of salt and alkali stress on S. corniculata through proteomics and metabolomics analysis to improve understanding of the resistance of plants. S. corniculata seedlings were exposed to salt and alkali stress for 72 h, respectively. Metabolic changes were quantified by conducting MS-based proteomics and NMR-based metabolomics analysis. The response of S. corniculata to salt stress was distinct from that of plants subjected to alkali stress at both physiological and molecular levels. The integrated-omic studies identified 22 and 19 differentially expressed proteins and metabolites mainly involved in carbohydrate metabolism and amino acid metabolism. On account of the up-regulation of energy metabolism and higher accumulation of organic osmolytes, S. corniculata shows high pH resistance when it suffers alkali stress. These findings provide insights into the different regulatory mechanisms in halophyte S. corniculata response to salt and alkali stresses.