Composition and diversity of endophytic bacterial communities in the tubers of Pinellia ternata from different regions and their effects on succinate biosynthesis based on high-throughput sequencing

In this study, high-throughput sequencing (HTS) technology was used to investigate the composition and diversity of endophytic bacteria and their effects on succinic acid biosynthesis in P. ternata tubers from three different geographical locations (MS, SL, and ZT). A total of 1777 amplicon sequence variants (ASVs) were annotated, and the diversity and composition of endophytic bacteria in P. ternata tubers were significantly different among different regions. The ZT samples presented the highest alpha diversity, and the Shannon diversity, richness, and Pielou evenness index were all ZT > MS > SL. Co-occurrence network analysis revealed that endophytic bacterial groups such as Stenotrophomonas, Pseudomonas, Mycobacterium, and Chryseomicrobium were key groups in the endophytic bacterial interaction network, indicating that they play a role in maintaining community stability. In addition, some endophytic bacteria were associated with the biosynthesis of succinic acid, a key bioactive compound in P. ternata. The succinate content was positively correlated with the genera Brevundimonas, Ensifer, Nocardioides, and Paenibacillus, while it was negatively correlated with the genera Lentimicrobium, Anaerovorax, and Pajaroellobacter. These findings highlight the key role of endophytic bacteria in regulating the efficacy of P. ternata. These findings provide key information for further elucidating the mechanism by which endophytic bacteria affect the synthesis of bioactive compounds.