Correlation Between Root Rot With Rhizosphere And Root Microorganisms And Mitigation Measures Of Panax Notoginseng

Panax notoginseng(Burk.)F.H.Chen is a plant of the Araliaceae genus and is a large variety of Chinese medicinal materials in China.At present,it has basically achieved standardized and large-scale planting.With the modernization of traditional Chinese medicine and the increase in market demand,more and more P.notoginseng are planted artificially,but they are easily affected by various diseases,and the root rot of P.notoginseng is particularly serious.Environmental microbes are the second genome of plants,and the composition of microbes is closely related to plant health.At present,there are many studies on the microbial community of P.notoginseng root rot,but amplicon sequencing(16S,18 S and ITS)is mostly used.The disadvantage of amplicon sequencing is that it cannot obtain information on all microorganisms in the environment.In order to explore the differences in the structure and function of microbial communities in healthy and diseased P.notoginseng rhizosphere soils and roots,this study used a metagenomics approach to systematically and comprehensively analyze healthy and diseased P.notoginseng rhizosphere soils and root microorganisms in different regions.To clarify the relationship between P.notoginseng root rot and microorganisms in the rhizosphere soil and roots,and to verify the potential pathogenic bacteria of root rot through experiments and screen out the potential antagonistic bacteria of P.notoginseng root rot.The main conclusions of this study are as follows:(1)Through data analysis,the results showed that the community of P.notoginseng rhizosphere soil was more diverse than that of root.Rhodopseudomonas,Actinoplanes,Burkholderia,Varovorax Paradox help P.notoginseng resist root rot.Ilyonectria mors-panacis and Pseudomonas fluorescens and Pseudopyrenochaeta lycopersici may be the pathogen of P.notoginseng root rot.(2)The results of functional annotation results showed that the up-regulation of amino acid transport and metabolism-related genes in rhizosphere soil would help P.notoginseng resist pathogenic bacteria.The related genes of ABC transporter family and gene modulating resistance family can improve the disease resistance of P.notoginseng,and the increase in the number of glycosyltransferase(GTs)and glycoside hydrolases(GHs)families may be the molecular level of P.notoginseng root rot.(3)Based on the binning results of metagenomic data,the binning results were evaluated and comprehensively analyzed,and high-quality bins were screened.Finally,a total of 54 high-quality bins with a completeness of 95% were screened.The complete genomes of two unknown Flavobacteriaceae species and one unknown Bacteroidetes species were also obtained based on the binning results.(4)The potential pathogenic bacteria of P.notoginseng root rot were verified by experimental,and the results showed that Ilyonectria mors-panacis and Pseudomonas fluorescens were the pathogenic bacteria of P.notoginseng root rot,and compared with the known pathogenic bacteria Fusarium oxysporum and Fusarium solani,it was found that the virulence of Ilyonectria mors-panacis was higher than that of Fusarium oxysporum and Fusarium solani,the pathogenicity of Pseudomonas fluorescens is between that of Fusarium oxysporum and Fusarium solani.(5)Antagonistic bacteria were screened from the isolated root microorganisms.Using Fusarium oxysporum and Fusarium solani as controls,two antagonistic bacteria were screened that had obvious inhibitory effects on both Fusarium oxysporum and Fusarium solani.This study reveals the structural and functional diversity of microbial communities in rhizosphere soil and root of P.notoginseng,providing a theoretical basis for better understanding the relationship between P.notoginseng root rot with rhizosphere and root microbes,and also provides theoretical support for the development related biological control agent of P.notoginseng root rot.