Multiomics Analyses of Two Sorghum Cultivars Reveal the Molecular Mechanism of Salt Tolerance

Sorghum [Sorghum bicolor (L.) Moench] is one of the most important cereal crops and contains many health-promoting substances. Sorghum has high tolerance to abiotic stress and contains a variety of flavonoids compounds. Flavonoids are produced by the phenylpropanoid pathway and performed a wide range of functions in plants resistance to biotic and abiotic stress. A multiomics analysis of two sorghum cultivars (HN and GZ) under different salt treatments time (0, 24, 48, and 72) was performed. A total of 45 genes, 58 secondary metabolites, and 246 proteins were recognized with significant differential abundances in different comparison models. The common differentially expressed genes (DEGs) were allocated to the flavonoid biosynthesis and phenylpropanoid biosynthesis pathways. The most enriched pathways of the common differentially accumulating metabolites (DAMs) were flavonoid biosynthesis, followed by phenylpropanoid biosynthesis and arginine and proline metabolism. The common differentially expressed proteins (DEPs) were mainly distributed in phenylpropanoid biosynthesis, biosynthesis of cofactors, and RNA transport. Furthermore, considerable differences were observed in the accumulation of low molecular weight nonenzymatic antioxidants and the activity of antioxidant enzymes. Collectively, the results of our study support the idea that flavonoid biological pathways may play an important physiological role in the ability of sorghum to withstand salt stress.

Automated summary

This study reveals the association between sorghum's tolerance to salt stress and the flavonoid biological pathway through multiomics analysis. Significant differences were also observed in other metabolic pathways and proteins. Additionally, the accumulation of low molecular weight nonenzymatic antioxidants and the activity of antioxidant enzymes may also affect sorghum's ability to withstand salt stress.