Biofertilizers regulate the soil microbial community and enhance Panax ginseng yields

Abstract

Background: Panax ginseng is widely used as functional food and traditional Chinese medicine. To satisfy the market supply and medication safety, biofertilizers are used as agents to stimulate the growth and production of P. ginseng. Methods: In this study, we used high-throughput sequencing and quantitative polymerase chain reaction to analyze microbial community in soils treated with biofertilizers during the development stages of P. ginseng. Ginsenoside content was detected using high-performance liquid chromatography analysis to evaluate the effects of biofertilizer application. Results: In this study, the incidence rate of P. ginseng root rot significantly declined by 40.3-47.3% after application of disease-biocontrol biofertilizers. Bacterial diversity showed increasing trends in soils treated with 3.0-4.5 ml kg-1 of disease-biocontrol biofertilizers compared with those in untreated soils. Principal coordinate analysis ordination revealed that bacterial communities were changed by biofertilizers depending on their application concentration. Relative abundance of potentially beneficial bacterial agents, such as Bacillus, Burkholderia, Rhizobium, Streptomyces, and Mycobacterium, significantly increased compared with that in control. Fusarium of low abundance observed in soils treated with biofertilizers compared with that in untreated soils. P. ginseng yield was enhanced by 17.0-19.1%, and ginsenoside (Rg1 and Rb1) contents were improved after biofertilizer application. Conclusions: Our results reveal that biofertilizers reduced the incidence rate of root rot, increased bacterial diversity, promoted the relative abundance of potentially beneficial bacterial taxa, decreased the abundance of potentially harmful bacterial agents, and then enhanced the yield and quality of P. ginseng.