The role of amino acid metabolism in salt tolerance mechanism of Medicago sativa and Medicago truncatula

Abstract

Abstract Backgroud: Soil salinization is a major issue of global concern today. Under salt stress, the growth and development of plants are slowed down and the yield is reduced, so it is particularly important to understand the salt resistance mechanism of plants. Meanwhile, amino acid metabolism has been shown by many studies to effectively alleviate most abiotic stresses including salt stress. Results: In this study, transcriptomics and proteomics were used to study the salt resistance mechanism of Medicago sativa and Medicago truncatula and the role of amino acid metabolism under salt stress. The results showed that the growth and development of the two alfalfa species were significantly inhibited under 50 mM NaCl stress, after KEGG enrichment analysis, it was found that most DEGs / DEPs were involved in amino acid metabolism. GSEA analysis showed that the two amino acid metanolism of Valine, leucine and isoleucine degradation and Tyrosine metabolism played important roles in the process of salt resistance. At the same time, leucine (Leu), isoleucine (Ile) and tyrosine (Tyr) were quantitatively determined. The results showed that under salt stress, the contents of the three amino acid increased significantly, and it was found that leucine had an important effect on the salt resistance of Medicago sativa while tyrosine effected more on the salt resistance of Medicago truncatula. Conclusion: This experiment revealed that the role of amino acid metabolism in Medicago sativa and Medicago truncatula under salt stress, meanwhile some amino acids can significantly improve the damage of plants to salt stress, which provides some help and theoretical basis for the growth and development of alfalfa spp. plants in saline-alkali land and the increase of yield in the future.