Isolation And Identification Of Higjh-salt Fun Gi From Three Areas Of The Yellow River Delt A And Molecular Phylogenetics Reserch

The Yellow River Delta region is very typical of saline soils,and the area can be used as a backup arable resource for the country.However,the soils in this area are poorly structured and prone to slumping.In this study,we identified and screened key salt tolerant fungi and identified the phylogenetic tree of salt tolerant fungi through gene sequencing and plate dilution.The above studies provide an important reference for the artificial improvement of soil colonies in the region and the mining of saltresistant active colonies.To this end,the following studies were carried out:(1)Dissecting changes in microbial communities at different salt concentrateons;(2)Finding correlations between changes in plant biomass and microbial communities at different salt concentrations;(3)Screening for key salt tolerant fungi;(4)A phylogenetic tree was constructed for the identified salt tolerant fungi based on high throughput sequencing to analyse the affinities between the species.The main findings of the study are as follows:1.In this study,336 samples were collected from high-salt environments,including 159 samples from Guangrao County,157 samples from Dongying District and 20 samples from Kenli District.After isolation and identification,a total of 397 hypersaline fungi were isolated and identified to 81 genera and 140 species by a combination of morphological and molecular biological methods,among which Fusarium,Streptomyces and Mesocystis were the most widely distributed in the hypersaline environment in Dongying City,Shandong Province.2.The community structure and species composition of culturable high-salt fungi in Gugrao County,Dongying District and Kenli District were studied.The number of culturable high-salt fungi in Dongying district was the highest(68),followed by Kenli District(38),and Gugrao County was the lowest(19).3.The number of high salt fungi on the taxonomic rank of each fungal species.High throughput sequencing techniques were used to analyse the soil fungal species in salt tolerant vegetation communities,and a total of 81 genera in 50 families from 4 phyla,9 orders and 23 families were obtained.The phylum Ascomycota,Mucoromycota,Basidiomycota and Mortierellomycota were included in thetaxonomic rank of the phylum.At the taxonomic level,they include:Sordariomycetes,Mucoromycetes,Eurotiomycetes,Dothi deomycetes,etc.At the taxonomic level,they include: Eurotiales,Mucorales,Hypocreales,Pleosporales,etc.At the taxonomic level,they include:Eurotiales,Mucorales,Hypocreales,Pleosporales,etc.Pleosporales,Moniliales,etc.;at the taxonomic level,the families include Aspergillaceae,Nectriaceae,Ophiocordycipit aceae,and Sarcocystis.aceae,Hypocreaceae,Choanephoraceae,Pleosporineae,Cladosporiaceae,etc.;at the taxonomic level of genera,they mainly include:Acremonium,Aspergillus,Cladosporiaceae.Fusarium,Microsphaeropsis,Mucor,Penicillium,Phoma,Purpureocillium,Rhizopus,etc.4.High throughput sequencing analysis of high-salt environment samples from Guangrao,Dongying and Kenli areas revealed a total of140 species of fungi in 3 phyla,9 orders and 23 families and 81 genera,with Ascomycota as the dominant phylum,Sordariomycetes as the most dominant phylum,Pleosporales as the overalldominant phylum,Pleosporineae as the dominant family of high saltfungi,and Fusarium as the most dominant genus in the genus level.5.On the basis of the taxonomy of this study,a phylogenetic study of the r DNA-ITS sequences of the 397 salt-tolerant fungi isolated and identified was carried out to construct a phylogenetic tree and analyse the affinities between the various genera.After phylogenetic analysis,it was found to be consistent with their morphologyical identification results.In this study,the composition and distribution characteristics of hypersaline fungal species in hypersaline environments in Shandong Province were initially clarified,and the fungal strains obtained during the study serve as valuable microbial resources,which can provide valuable candidate strains for subsequent research on hypersaline gene discovery and active metabolite development.