Abstract: To analyzed the effects of applyingBacillus proteolyticus, Raoultella ornithinolytica, Burkholderia gladioli, andBacillus siamensison the growth, physiological indicators, and total flavonoid content ofGynostemma pentaphyllumwere investigated in this study. The results indicated that the light response curve ofG. pentaphyllumleaves exhibited similarities in trend across different treatments, albeit with certain distinctions in high light response. The plants were subjected to a certain degree of stress due to the bacterial fermentation broth.B. proteolyticusexhibited a positive impact on the promotion of leaf and stem growth. Compared with the control group, the treatment groups demonstrated a significant decrease in POD activity and soluble sugar content. However, there was no significant change in proline content. Additionally, the SOD activity ofG. pentaphyllumtreated withB. proteolyticus, R. ornithinolyticaandB. siamensisexhibited a notable decrease. The total flavonoid content ofG. pentaphyllumtreated withR. ornithinolyticawas highest at 3.85 mg/g, representing a 237.72% increase compared to that of the control. Application ofR. ornithinolyticawas demonstrated to effectively promote the growth and accumulation of total flavonoid content inG. pentaphyllum, yielding optimal effect. This study established a scientific basis for the development of advanced microbial fertilizers and agents to optimize the cultivation yield and enhance the quality ofG. pentaphyllum.

Key words: Bacillus proteolyticus, Raoultella ornithinolytica, Burkholderia gladioli, Bacillus siamensis, Gynostemma pentaphyllum, total flavonoids content