Ginsenosides in root exudates of Panax notoginseng drive the change of soil microbiota through carbon source different utilization

Ginsenosides are the main bioactive components of Panax plants which could be secreted by root and show autotoxicity to root cells or promote the growth of soil-borne pathogens. However, comprehensive understanding of the effect of ginsenosides on soil microbiota is still lacking. The ginsenosides in root exudates of P. notoginseng were quantified and exogenous ginsenosides on soil microbiota were tested using 16S rRNA and ITS gene tag sequencing. Then its underlying mechanism was deciphered through studying effects of ginsenosides on growth of the ginsenoside-modified culturable fungi and bacteria as well as the relationships between these fungi and bacteria. Exogenous root exudates and mixtures of Rg1 + Rb1 + Rd had similar ability to drive the change of soil microbiota. Further studies demonstrated that Rg1 + Rb1 + Rd mixture could enrich or suppress special fungi and bacteria to modify soil community through differential utilization of carbon source during the early stage (30 days), followed by antagonism between ginsenoside-modified fungi and bacteria to determine soil microbial community modification at later stage (60 and 90 days). Ginsenosides were the main substances in exogenous root exudates of P. notoginseng that drove the change in soil microbiota, mediating the special interaction between the plant and the microbiota.