Volatile organic compounds from medicinal plant Codonopsis radix: Unraveling rhizoplane microbiome interactions for...

Plant roots emit a diverse array of volatile organic compounds (VOCs) to attract specific soil microorganisms, thereby promoting their growth and development. However, the mechanisms by which medicinal plants interact with surrounding microorganisms through VOCs to enhance their quality remain poorly understood. This study integrated microbiome, transcriptome, and metabolome analyses to investigate the VOCs that mediate interactions between rhizoplane microorganisms and Codonopsis radix plants. The research identified a total of 36 common VOCs in the roots of Codonopsis radix, with 2, 3, 5-trimethylpyrazine being the primary VOC responsible for the root's nutty flavor. Chemoheterotrophic microorganisms, including both saprophytes and arbuscular mycorrhizae, were found to be the dominant types in the rhizoplane. The rhizoplane microorganism Rugamonas was significantly positively correlated with naringin and 2-ethyl-3-methylpyrazine. Furthermore, VOCs were found to influence the accumulation of phenylpropane differential metabolites and the expression of genes involved in phenylpropane synthesis and metabolite accumulation by modulating the structure and diversity of rhizoplane microbial communities. Overall, this study provides valuable insights into the complex interactions between medicinal plants and microorganisms, as well as potential strategies for enhancing the quality of medicinal plants.