Deciphering drought adaptation in Eucommia ulmoides: From the rhizosphere microbiota to root metabolites

Abstract

Rapid global climate change has made drought stress a significant limiting factor for plant growth and productivity. While the effects of drought on plant metabolism and the rhizosphere microbiota are well-documented, our understanding of their dynamically interplay and potential synergies in enhancing plant adaptability during droughts is incomplete. Herein, using Eucommia ulmoides as a model system under drought stress and integrating metagenomic sequencing, untargeted metabolomics, and plant physiological assessments, We found that drought altered the root metabolites profile of E.ulmoides, notably enriching the flavonoid 6”-O-Acetylgenistin. Additionally, the co-occurrence network of rhizosphere microbiota shifted dynamically under drought, with core taxa including Bordetella, Janthinobacterium, Methylobacter, Noviherbaspirillum, Pseudomonas, Acidovorax, Variovorax, and the rare taxa Tindallia showing significant correlations with soluble sugars (SS), as was the key metabolite 6”-O-Acetylgenistin. Collectively, root metabolites and core rhizosphere taxa influence plant functional traits, enhancing the plant's adaptability to drought stress. These findings offering novel insights into strategies to increase plant adaptation during droughts.