Organically managed Sanqi alters the soil C metabolism and purine metabolism pathway through metagenomic and metabolomic analyses

Aims

Panax notoginseng (Sanqi), organically cultivated in the forest understory, has been shown to enhance its quality. However, the impact of organically vs. conventionally managed Sanqi on soil community composition, function, and metabolites remains unclear.

Methods

Here, we compared various land use patterns, including monoculture pine (MP), organically managed Sanqi (OMS), and conventionally managed Sanqi (CMS), to explore the diversity, function, and metabolism of the soil microbiome using metagenomic and metabolomic techniques.

Results

Our findings revealed that OMS and MP exhibited similar microbial α-diversity, community structure, and function as opposed to CMS. Moreover, both the OMS and CMS demonstrated a higher level of microbial complexity and stability than the MP, with respective enhancements ranging from 1.106% to 1.359% and 1.037% to 1.113%. Acidobacteria and Bradyrhizobium japonicum were significantly enriched in OMS but not in CMS. The OMS soils exhibited a notable enhancement in the carbon fixation pathway. In addition, differential metabolites such as deoxynucleosine, hypoxanthine, deoxyadenosine, deoxyguanosine, inosine, and guanine were found in the highest content in the OMS soils, primarily enriched in the purine metabolism pathway of nucleotide metabolism (map01232). OMS exhibited two additional factors (microbial α-diversity and community structure) directly influencing soil metabolites compared with CMS.

Conclusion

OMS significantly enhances microbial complexity and stability and the accumulation of beneficial metabolites. As a result, the land use conversion from MP to OMS fosters the development of a more stable and healthier soil environment, thereby providing a robust ecological foundation for the growth of Sanqi.

Graphical abstract