Nitrogen application regulates antioxidant capacity and flavonoid metabolism, especially quercetin, in grape seedlings under salt stress

• DOI: 10.1016/j.jia.2024.07.013
• Publication Date: 2024-07-14T05:28:14Z
• Authors: Congcong Zhang; Han Wang; Guojie Nai; Lei Ma; Xu Lu; Haokai Yan; Meishuang Gong; Yuanyuan Li; Ying Lai; Zhihui Pu; Li Wei; Guiping Chen; Ping Sun; Baihong Chen; Shaoying Ma; Sheng Li

Salt stress is a typical abiotic in plants that causes slow growth, stunting, and reduced yield fruit quality. Fertilization necessary to ensure proper crop growth. However, the effect of fertilization on salt tolerance grapevine unclear. In this study, we investigated nitrogen fertilizer (0.01 0.1 mol L−1 NH4NO3) application (200 mmol NaCl) based physiological indices, transcriptomic metabolomic analyses. The results revealed 0.01 NH4NO3 supplementation significantly accumulation superoxide anion (O2.-), enhanced activities dismutase (SOD) peroxidase (POD), improved levels ascorbic acid (AsA) glutathione (GSH) grape leaves compared treatment alone. Specifically, joint transcriptome metabolome analyses showed differentially expressed genes (DEGs) accumulated metabolites (DAMs) were enriched flavonoid biosynthesis pathway (ko00941) flavone flavonol (ko00944). particular, relative content quercetin (C00389) was markedly regulated by nitrogen. Further analysis exogenous foliar SOD POD activities, increased AsA GSH contents, H2O2 O2.- contents. Meanwhile, 10 hub DEGs, which had high Pearson correlations (R2 > 0.9) with quercetin, repressed conclusion, all indicated moderate under antioxidant system defense response, thus providing new perspective for improving grapes.