Endophytes Diversity And The Correlation With The Dendrobine Content In Dendrobium Nobile Lindl.

Endophytes can form a symbiotic relationship with host,which can promote growth and development of host,produce the same or similar substances as secondary metabolism,and play an important role in plant micro ecosystem.This study was based on the Culture independent and high-throughput sequencing,research of Dendrobium nobile Lindl seeds,tissue culture seedling and imitation of the wild Dendrobium nobile Lindl of endophyte,and its rhizosphere soil microbial total DNA,further analysis of the endophyte diversity.The content of different part of Dendrobium nobile Lindl dendrobine with different months was checked by the gas chromatography,and through principal component analysis and correlation analysis to determine the relationship between endophytes and dendrobine content in Dendrobium nobile Lindl.The main results of this study were as follows:1.Seeds of Dendrobium nobile Lindl endophytic bacteria mainly include Proteobacteria and Cyanobacteria,13 genera.The main group of it was Proteobacteria and the dominant genera was Pantoea.Shannon index and Simpson index respectively were 1.822 and 0.689,chao1 index was 11.Tissue culture seedling endophytic bacteria mainly include Proteobacteria,Cyanobacteria and Firmicutes.Proteobacteria and Cyanobacteria were the main groups,and the root,stem and leaf of endophytic bacteria were classified into 12,16 and 15 genera which dominant genera was Pantoea.Shannon index was 0.960,1.557 and 1.352,Simpson index was 0.425,0.567 and 0.509,chao1 index was 16.000,15.333 and 12.333.Imitatied wild Dendrobium nobile Lindl endophytic bacteria mainly include Proteobacteria,Cyanobacteria and Firmicutes.Proteobacteria and Cyanobacteria were the main groups,and the root,stem and leaf of endophytic bacteria were classified into 1086,1387 and 1075 genera,which dominant genera in root was Pseudomonas,endophytic bacteria in the stems and leaves of dominant genera were Escherichia-Shigella.Shannon index was 2.794,1.828 and 2.810,Simpson index was 0.637,0.425 and 0.507,chao1 index was 737.411,385.812 and 959.738.Dendrobium nobile Lindl rhizosphere bacteria mainly include Cyanobacteria and Proteobacteria,1918 genera,the main group of it was Cyanobacteria,and the dominant genera was Bacillus.Shannon index and Simpson index respectively was 7.296 and 0.925,chao1 index was 1973.580.The diversity of bacteria was Rhizosphere soil > Imitation wild Dendrobium nobile Lindl > Seeds > Tissue culture seedlings.2.Seeds of Dendrobium nobile Lindl endophytic fungi mainly include Ascomycota and Basidiomycota,23 genera.The main group of it was Ascomycota,and the dominant genera was Debaryomyces.Shannon index and Simpson index respectively was 0.168 and 0.036,chao1 index was 29.5.Tissue culture seedling endophytic fungi mainly include Ascomycota,Basidiomycota and Zygomycota,Basidiomycota and Zygomycota were the main groups,and the root,stem and leaf of endophytic fungi were classified into 28,16 and 22 genera,which dominant genera in root was Byssochlamys,the dominant genera in stems was Mortierella,Conocybe and Debaryomyces were dominant genera in leaves.Shannon index was 0.090,0.088 and 0.094,Simpson index was 0.015,0.016 and 0.017,chao1 index was 28.750,18.000 and 22.333.Imitatied wild Dendrobium nobile Lindl endophytic fungi mainly include Basidiomycota,Ascomycota and Zygomycota,Basidiomycota and Ascomycota were the main groups,the root,stem and leaf of endophytic fungi were classified into 377,248 and 274 genera,and the dominant genera were Dactylaria,Thermoascus and Neofusicoccum in root,stems and leaves.Shannon index was 0.671,0.157 and 0.695,Simpson index was 0.173,0.026 and 0.179,chao1 index was 912.145,94.911 and 183.944.Dendrobium nobile Lindl rhizosphere fungi mainly include Basidiomycota and Ascomycota,862 genera.The main group it was Basidiomycota,and the dominant genera was Rickenella.Shannon index and Simpson index respectively was 4.531 and 0.850,chao1 index was 858.330.The diversity of fungi was Rhizosphere soil > Imitation wild Dendrobium nobile Lindl> Seeds > Tissue culture seedlings.3.The content of dendrobine in root,stem and leaf of wild Dendrobium nobile Lindl was between 1.502 and 8.093 mg/g.From November to September of the following year,the content of dendrobine in roots and stems showed a trend of decreasing at first,then increasing and then decreasing.In May,the content of dendrobium was highest in roots and stems,but lowest in September,there was significant difference in dendrobine content between May and September(P<0.05).The content of dendrobium in leaves reached the highest in November and the lowest in July,and there was significant difference in dendrobine content among March,May,July and November(P<0.05).4.Analysis of correlation and principal component of Dendrobium nobile Lindl endophyte structure and dendrobine content.The results showed that:In roots,the endophytic bacteria unidentified_Chloroplast,Duganella and endophytic fungi Dactylaria,Luellia were positively related to the content of dendrobine,while the endophytic bacteria Geothermobacter,Pantoea and endophytic fungi Rickenella were negatively related to the content of dendrobine.In stems,the endophytic bacteria Paenibacillus and Burkholderia were positively related to the content of dendrobine,while the endophytic bacteria Acinetobacter,Curvibacter and endophytic fungi Dactylaria,Cyphellophora,Candida and Olpidiaster were negatively related to the content of dendrobine.In leaves,the endophytic bacteria Shewanella,Pseudomonas,Halomonas and endophytic fungi Eriosporella,Aspergillus and Talaromyces were positively related to the content of dendrobine,while the endophytic bacteria Crenothrix and endophytic fungi Alternaria,Brycekendrickomyces,Gibberella were negatively related to the content of dendrobine.