Utilizing transcriptomics and metabolomics reveal drought tolerance mechanism in Nicotiana tabacum

The development and growth of plants are significantly impacted by adverse surroundings, particularly drought conditions. The yield and quality of plants, in particular, are heavily reliant on the presence of favorable growth conditions. Here, we performed comprehensive research to investigate phenotype, physiological characteristics, transcriptomic and metabolomic changes in Nicotiana tabacum (N. tabacum) in responses to drought stress (DS). This work aimed to investigate the detailed responses of N. tabacum to DS under different drought conditions (CK, well-watered; LD, light drought; MD, moderate drought and SD, severe drought). N. tabacum grew normally under CK but was inhibited under LD, MD and SD stress; the relative water content, transpiration rate and protective enzyme activity significantly influenced under DS. In the LD/CK, MD/CK and SD/CK comparison groups, there were 7483, 15558 and 16876 differentially expressed genes (DEGs), respectively, and 410, 485 and 523 differentially accumulated metabolites (DAMs), respectively. The combined analysis of transcriptomic and metabolomic data unveiled the significant involvement of phenylpropanoid biosynthesis in the N. tabacums response to drought stress. These findings characterized the key metabolites and genes in responses to drought stress in N. tabacum, hence offering valuable insights into the underlying mechanisms driving these responses to DS and maintaining plant health under climate change.