Structural Diversity And Saponin Relevance Of The Endophytic Flora Of Paris Polyphylla Var.Yunnanensis

The Paris genus has a profound history of use as Chinese herbal medicine in China,and the important medicinal value of Paris polyphylla var.yunnanensis,which is a local medicinal herb in the southwest of China,is gradually gaining widespread attention.In this study,12 different species of Paris polyphylla var.yunnanensis from Yunnan were selected as samples(numbered A-L respectively),and their root samples were firstly cultured to isolate root endophytic bacteria and fungi,and the diversity of total endophytic bacteria in the roots of Paris polyphylla var.yunnanensis was analyzed by high-throughput sequencing technology,and the correlation between the total endophytic bacteria in the roots of 12 species of Paris polyphylla var.Yunnanensis and their saponin content and the types of significantly correlated flora were analyzed separately.The main findings were as follows:(1)455 culturable endophytic bacteria were isolated from the roots of Paris polyphylla var.Yunnanensis from 12 different regions and grouped into 31 genera and86 species,of which Bacillus and Bacterium were dominant;197 culturable endophytic fungi were isolated and grouped into 17 genera and 45 species,of which Fusarium was the dominant genus.(2)By comparing all the 31 genera of bacteria isolated from the roots of 12 samples of Paris polyphylla var.Yunnanensis in parallel,Bacillus accounted for the largest proportion of bacteria in A,B,D,I,K,and L;Bacterium accounted for the largest proportion in C,G,and H;the number of Bacillus and Bacterium in E and F is about the same,and both are major genera;Klebsiella is the major species in J;Klebsiella also occupies a large proportion in G and L;Pantoea occupies a minor position in B,and a small proportion in F.Among the fungi,Fusarium accounted for the largest proportion in A,C,D,F,G,H,I,J,K,and L,of which only the genus was isolated in H,I,J,and K.Fusarium and Clonostachys were among the dominant groups in B,together accounting for more than 50%;Fusarium and Aspergillus were dominant in E,together accounting for more than 60%.(3)High-throughput sequencing was used to analyze the diversity of total endophytic bacteria in roots,yielding 2579 bacterial OTUs,with the dominant phylum Proteobacteria and the dominant genus group mainly being Pseudomonas;1520fungal OTUs were produced,with the dominant phylum group being Ascomycota,the dominant genus groups were Thermoascus and Kazachstania.The diversity of total endophytic bacteria in roots was significantly higher than that of fungi.(4)By analyzing the correlation of total endophytic bacteria of Paris polyphylla var.yunnanensis roots with their five saponins,it was found that endophytic bacteria of Bacillus genus had significant correlation with saponin Ⅶ and saponin H,while endophytic Thermoascus genus,Kazachstania genus and Thermomyces genus were significantly correlated with saponin Ⅶ,saponin H and saponin D.Saponin Ⅰ and saponin Ⅱ were not significantly correlated with endophytic fungi in the roots of Paris polyphylla var.yunnanensis.