Study On The Composition And Diversity Of Rhizosphere Bacterial Community During Different Growth Stages Of Eremopyrum

The rhizosphere microorganisms of plants are closely related to the material cycle in the soil,as well as the host’s nutrient absorption,resistance to diseases and pests,and stress adaptation.Rhizosphere microorganisms are influenced by various factors such as host plant species and origin.Among them,polyploidy,as a general and violent genetic variation in nature,affects not only the plants themselves,but also the formation of microbial diversity in rhizosphere? Scientific questions about how this affects microbial replenishment and community composition remain unclear.Eremopyrum(Ledeb.)Jaub et.Spach is an annual plant group of Triticeae including diploid and tetraploid cell ploidy levels.It has the advantages of multiple tillers,high photosynthetic efficiency,disease resistance and stress tolerance,and is an important germplasm resource for forage and wheat breeding and ecological protection.In this study,seven numbered materials of two ploidy species of Eremopyrum were used as research objects,and high-throughput sequencing technology was used to analyze the phenotypic traits,soil physical and chemical properties,and rhizosphere bacterial community changes of different ploidy species of Eremopyrum at different growth stages.The main results were as follows:(1)The phenotypic traits and soil physical and chemical properties of different ploidy plants of Eremopyrum were different at different growth stages.Polyploid species had higher plant height(PH),leaf length(LL),and flag leaf length(FLL)and width(FLW)values compared to diploid species,while leaf width(LW),stem diameter(SD),and tiller number(NT)values were lower.Among them,there were significant differences in PH,LL,LW,and SD values among different groups during the seedling stage.At the tillering and heading stages,Eremopyrum plants significantly affected the content of available phosphorus(AP)and organic matter(OM)in soil.The content of alkaline hydrolyzable nitrogen(AN)in different periods of E.orientale soil was relatively high,with the p H and water content(SWC)in E.triticeum soil are relatively low.(2)The dominant bacteria phyla in soil include Proteobacteria,Acidobacteria,Firmicutes,Actinobacteria and Bacteroidetes.The abundance of rhizosphere bacteria of different ploidy species of Eremopyrum was different,and the number of different bacterial groups among different species increased with the growth period.Diploid species had higher abundance of Proteobacteria and Pseudomonas,while polyploid species had higher bacillus of Massilia,Paenibacillus and RB41.(3)The rhizosphere bacterial prediction function of different ploidy species of Eremopyrum changed significantly with plant growth period.The abundance of microbial communities related to chemoheterotrophy and ureolysis in the rhizosphere of polyploid seedlings was higher,the abundance of bacteria related to aerobic chemoheterotrophy in the rhizosphere during the late growth stage of E.triticeum was higher.(4)Soil bacterial community ɑ-diversity indices of Chao 1,ACE,Shannon and Inv Simpson,were found lowest performance at E.triticeum rhizosphere in plant life stages.Correlation analysis showed that soil physical and chemical factors such as water content(SWC),organic matter(OM)and available phosphorus(AP)were significantly correlated with the composition and the diversity index of bacterial community.The stem diameter(SD)were significantly correlated with the diversity index of bacterial community,part of phenotypic traits were also significantly correlated with the relative abundance of some soil bacterial groups.In conclusion,the phenotypic characters of different ploidy plants of Eremopyrum were different in different growth periods,and had formed the influence on soil nutrient elements and rhizosphere community.The interaction and regulation of plants,soil,and rhizosphere bacteria together constituted their diverse rhizosphere ecology and functions,playing an important role in plant growth and health.This paper revealed the dynamic changes of plant properties,soil physical and chemical properties and composition and diversity of rhizosphere bacterial community during the growth of different ploidy Eremopyrum species.Clarified the correlation between rhizosphere bacterial community of Eremopyrum plants,soil physical and chemical properties,and plant phenotype.