Integrative transcriptomic, metabolomic, and physiological analyses reveal the root adaptive mechanisms of common vetch (Vicia sativa L.) under drought stress

ABSTRACT: Drought is a major abiotic stress that limits the productivity and ecological adaptability of leguminous forage crops. As the primary organs that sense soil water deficits, roots play an essential role in plant adaptation to drought. Common vetch (Vicia sativa L.) is an important annual leguminous forage crop widely used for forage production, green manure, and ecological restoration. However, the molecular mechanisms underlying cultivar-specific root responses to drought stress remain poorly understood. In this study, integrated transcriptomic (RNA sequencing, RNA-seq) and widely targeted metabolomic (liquid chromatography-mass spectrometry, LC-MS) analyses were conducted to systematically characterize drought-responsive mechanisms in the roots of a drought-tolerant cultivar LuQuan common vetch(LQ) and a drought-sensitive cultivar LanJian NO.1(LJ). LQ exhibited greater drought tolerance than LJ, accompanied by more effective transcriptional regulation and metabolic reprogramming under drought stress. Compared with LJ, LQ showed marked activation of flavonoid biosynthesis, leading to the substantial accumulation of antioxidant metabolites, including kaempferol, luteolin, galangin, isoliquiritigenin, and phloretin. Enhanced α-linolenic acid metabolism also contributed to the maintenance of membrane lipid homeostasis and the regulation of stress signaling. Furthermore, weighted gene co-expression network analysis (WGCNA) combined with transcriptome–metabolome association analysis identified multiple hub genes associated with flavonoid metabolism, lipid oxidative metabolism, and antioxidant enzyme activities. These genes were strongly correlated with key metabolites and the activities of peroxidase (POD), superoxide dismutase (SOD), and catalase (CAT), forming a tightly interconnected regulatory network. These findings suggest that the drought-tolerant cultivar LQ improves drought adaptation through a coordinated regulatory network integrating flavonoid metabolism, lipid metabolism, and antioxidant enzyme activity, thereby maintaining redox homeostasis in roots under drought stress. This study identifies flavonoid metabolism as a central link between lipid metabolic remodeling and antioxidant defense and provides insight into the molecular basis of drought tolerance. It also identifies candidate genes for developing improved drought-resistant germplasm.

INSTRUMENT(S): Liquid Chromatography MS - negative - reversed-phase-chromatography, Liquid Chromatography MS - positive - reversed-phase-chromatography

PROVIDER: MTBLS15164 | MetaboLights | 2026-07-27

REPOSITORIES: MetaboLights