Diversity Of Bacterial Community In Rhizosphere Soil Of Three Invasive Plants In Yunnan Province

Eupatorium adenophora,Tithonia diversifolia,and Eupatorium odoratum are three invasive plants in Yunnan Province,which are classified as high-risk quarantine in China and have strong reproductive ability and competitiveness.These three invasive plants often form dominant populations in the invasive land,seriously damaging the ecosystem structure and function of the invading land.At present,the mechanism of invasion of T.diversifolia and E.odoratum is not clear,and there are relatively few studies on the biogeography of E.adenophorum and soil microbes.In this study,three invasive plants of E.adenophorum and the same invasive land were used as research objects.Phospholipid fatty acids(PLFAs)and 16 s rDNA high-throughput sequencing technology were used to detect and analyze microbial communities in rhizosphere soil,and to explore soil bacterial community structure and the relationship between environmental factors further improves the mechanism of alien weed invasion.The specific research results are as follows:1.In the rhizosphere soil of different invasive land of Eupatorium adenophorum,the contents of various microbes were different;the proportion of bacteria in soil microbes in the invading sites was higher than 60%.The soil bacteria in each invasive land are similar in species,and the relative abundances of different species are different.Among them,the relative abundance of Proteobacteria is the highest,the proportion in the bacterial community is more than 30%.At the genus level,there are different dominant genera in different invasive sites,and the same species are in the same species.The content of different invasive areas varies greatly.Available potassium,organic matter,invertase,urease and protease in soil are the main factors affecting the composition of soil bacterial community structure.1.In the rhizosphere soil of different invasive land of Eupatorium adenophorum,the contents of various microbes were different.The ratio of bacterial content in the rhizosphere soil of A.adenophora to the total amount of microorganisms in each sampling area was higher than 60%.The soil bacterial concentration in Y2 was significantly higher than other samples,reaching 123.74 ?g/g,but the number of phyla,families and genera detected in this area was lower than other sample areas.At the level of the phylum,the top five phyla with the highest relative abundance in all soil samples are Proteobacteria,Actinobacteria,Acidobacteria,Bacteroidetes,and Verrucomicrobia.In all soil samples,the relative abundance of Proteobacteria is the highest,whose proportion in the bacterial community is more than 30%.At the genus level,the four sample areas have different advantage genera.The dominant groups in Y1 are Pirellula and Bacillus,and the dominant bacteria in Y2 are Lactobacillus,Mycobacterum and Bradyrhizobium,the dominant bacterium in Y3 and Y4 is Sphingomonas and Psedomona respectively.The environmental factors such as soil available potassium,ammonium nitrogen,organic carbon,sucrase,urease and protease have significant correlation with soil bacterial community Alpha diversity index;environmental factors such as soil available potassium,nitrate nitrogen,organic carbon,invertase,urease and protease affect the bacterial community composition in the rhizosphere soil of A.adenophora.2.There were differences in the content of various microbes in the rhizosphere soil of the E.adenophora,T.diversifolia,and E.odoratum of Pu'er University.The proportion of bacteria in the rhizosphere soil microbes of each plant was the higher than 65%.The number of bacteria phylum in the three soil samples was 42 to 44.At the level of the phylum,the top five phyla with the highest relative abundance in all soil samples are Proteobacteria,Actinobacteria,Acidobacteria,Bacteroidetes,and Verrucomicrobia.Accounting for bacterial communities,the ratios are all over 40%.At the genus level,the three soil samples contain different dominant genus and no common genus,and the dominant genus in Y5 is Novosphingobium and Bacillus.In Y6,the dominant genus are Sphingomonas,Bradyrhizobium,etc.The dominant genus in Y7 are Pseudomonas,Planctomyces,etc.There was a significant correlation between soil pH,available potassium,nitrate nitrogen,organic carbon and the Alpha diversity index of bacterial communities.Soil available factors such as available phosphorus,available potassium,ammonium nitrogen and organic carbon were closely related to bacterial community composition.