合成菌群对大豆根际和根内微生物群落的影响OA北大核心CSTPCD

Plant growth-promoting rhizobacteria(PGPR)are widely used to improve soil nutrient content and promote plant growth and health.However,the growth-promoting effects of a single PGPR on plants are limited.To explore the effects of synthetic micro-bial communities on soybean growth,rhizosphere,and endophytic microbiota,soybean PGPR was used to construct four synthetic microbial communities(SynComs)based on functional complementarity and efficacy stacking principles.The optimal community was chosen for its growth-promoting effects,and metagenomic sequencing was performed on its rhizosphere soil,while roots under-went 16S rRNA gene sequencing.This aimed to investigate the microbial community structure and functional changes of bacteria in both the soybean rhizosphere and endosphere.Pot experiments showed that SynCom 4 significantly increased soybean plant height,aboveground fresh weight,root length,root fresh weight,and nodule number.SynCom 4 comprised Klebsiella JP07,Klebsiella GD04,Pseudomonas LH19,Acinetobacter JP32,Klebsiella PKO08,Bacillus JK32,Stenotrophomonas GD03,and Klebsiella LH13.Principal component and community composition analyses were performed using the metagenomic sequencing data,uncovering sig-nificant changes in the rhizosphere microbial community structure after treatment with SynCom 4.Ten major phyla,including Proteo-bacteria,Firmicutes,and Actinobacteria,were identified at the phylum level.LEfSe analysis indicated an increase in the relative abundance of taxa such as unclassified_Acidimicrobiia,Luteimonas,unclassified_c_Chloroflexia,and unclassified_o_Thermoan-aerobacteroles in SynCom 4.Introducing SynCom 4 increased the relative abundance of functional genes associated with nitrogen metabolism,phosphorus transformation,and indole acetic acid,and gibberellin biosynthesis.According to 16S rRNA gene sequen-cing results,community composition analysis revealed that the dominant bacterial phyla in the endosphere included Proteobacteria,Firmicutes,Bacteroidetes,and Actinobacteria.Inoculation with SynCom 4 increased the diversity of the soybean endosphere bacteri-al community.LEfSe analysis demonstrated an increase in the relative abundance of taxa such as unclassified_f_Xanthomonadaceace,Hydrogenophaga,unclassified_o_Rhizobiales,and norank_f_Xanthobacteraceae following the application of SynCom 4.PICRUSt2 functional predictions indicated that SynCom 4 enhanced functions related to synthesizing amino acids,vitamins,lipids,and second-ary metabolites.In summary,metagenomic and 16S rRNA gene sequencing results indicated that SynCom 4 significantly altered the structure and composition of the rhizosphere and endosphere microbial communities.This intervention led to increased microbial di-versity and an elevated relative abundance of microbes.The application of SynCom 4 effectively promoted soybean growth and changed the structure and function of the bacterial microbial community in the rhizosphere and endosphere.