The Composition of Root-Associated Bacteria and Fungi of Astragalus mongholicus and Their Relationship With the Bioactive Ingredients

Abstract

Astragalus membranaceus (Fisch.) Bge. var. mongholicus, which is used in traditional Chinese medicine, contains several bioactive ingredients. The root-associated microbial communities play a crucial role in the production of secondary metabolites in plants. However, the correlation of root-associated bacteria and fungi with the bioactive ingredients production in A. mongholicus has not been elucidated. This study aimed to examine the changes in soil properties, root bioactive ingredients, and microbial communities in different cultivation years. The root-associated bacterial and fungal composition was analyzed using high-throughput sequencing. The correlation between root-associated bacteria and fungi, soil properties, and six major bioactive ingredients were examined using multivariate correlation analysis. Results showed that soil properties and bioactive ingredients were distinct across different cultivation years. The composition of the rhizosphere microbiome was different from that of the root endosphere microbiome. The bacterial community structure was affected by the cultivation year and exhibited a time-decay pattern. Soil properties affected the fungal community composition. It was found that 18 root-associated bacterial operational taxonomic units (OTUs) and four fungal OTUs were positively and negatively correlated with bioactive ingredient content, respectively. The abundance of Stenotrophomonas in the rhizosphere was positively correlated with astragaloside content. Phyllobacterium and Inquilinus in the endosphere were positively correlated with the calycosin content. In summary, this study provided a new opportunity and theoretical reference for improving the production and quality of in A. mongholicus, which thus increase the pharmacological value of A. mongholicus.

Root endophytic bacterial community composition of Aconitum carmichaelii debx. from three main producing areas in China

“…Previous studies found that some endophytic bacteria of Macleaya cordata and Astragalus mongholicus showed significant correlation with the contents of alkaloids [47,48]. They inferred that difference in the contents of alkaloids by the host or host compartments may contribute to difference in the endophytic bacterial community structure [47,48]. In this study, RDA and Pearson correlation analysis uncovered that five endophytic bacterial genera showed significant correlation with four alkaloids contents of A. carmichaelii Debx.…”

“…Some endophytes can produce or transfer host plants' secondary metabolites [3] and host plant metabolites can shape the root microbiota [14,15]. Previous studies found that some endophytic bacteria of Macleaya cordata and Astragalus mongholicus showed significant correlation with the contents of alkaloids [47,48]. They inferred that difference in the contents of alkaloids by the host or host compartments may contribute to difference in the endophytic bacterial community structure [47,48].…”

Contributions of Beneficial Microorganisms in Soil Remediation and Quality Improvement of Medicinal Plants

“…Glomus intraradices altered the relative quantity of essential oil patterns and significantly increased bornyl acetate, 1,8-cineole, α- and β-thujones in Salvia officinalis [ 242 ]. Li et al [ 256 ] found that bacterial and fungal community composition around the rhizosphere varied over the cultivation years of Astragalus mongholicus . The richness of Stenotrophomonas was positively correlated with astragaloside content, while Phyllobacterium and Inquilinus were positively correlated with calycosin content in roots.…”

Elucidating the interaction of rhizosphere bacteria and environmental factors in influencing active ingredient content of Lycium barbarum fruit in China

“…In recent years, more and more studies have focussed on the correlation between PGPR and active ingredients of medicinal plants. Root‐associated bacteria and fungi played a crucial role in the production of secondary metabolites, such as astragaloside and calycosin by Astragalus membranaceus (Li et al, 2021). The application of arbuscular mycorrhiza fungi and PGPR played a significant role in increasing yields, bioactive compounds and nutrition in the medicinal plant Basil (Khalediyan et al, 2021).…”