Taxonomy And Diversity Of Gliomastix And Phialophora

The genus Gliomastix was established by Guéguen(1905)and now is classified into Ascomycota,Sordariomycetes(Hypocreales,Bionectriaceae).Genus Phialophora was established by Medlar(1915)and belongs to Ascomycota,Eurotiomycetes(Chaetothyriales,Herpotrichiellaceae).Species of Gliomastix and Phialophora are saprophytic or weakly parasitic fungi which are widespread in soil.Gliomastix fungi have potential applications in medicine,agriculture and Industry,and Phialophora fungi are pathogens of many kinds of plants and human beings.It is essential to identify both genera fungi accurately for research and application them.About 500 soil samples were collected from Guiyang,Zunyi,Kaili,Bijie and Fuzhou from 2016 to 2018,and more than 300 fungal isolates were got from those samples using dilution plate methods.By identification,11 strains belong to Gliomastix,7 ones belong to phialophora-like.we can isolate Gliomastix from all the cities mentioned above,and it shows that this genus is widespread in soil.21 Gliomastix strains and 22 Phialophora strains are from Shangdong Agricvulture University collected from Guizhou,Hubei,Hainan,Guangxi,Sichuang and Qinghai,etc.On the basis of morphology of Gliomastix,Internal Transcribed Spacer(ITS),Nuclear Large Subunit ribosomal DNA(LSU rDNA),Nuclear Small Subunit ribosomal DNA(SSU rDNA),RNA polymerase II second largest subunit(rpb2)and β-tubulin(tub2)gene regions were utilized to do phylogenetic analysis and analysis gene regions differentiation and credibility by building single and multigene tree,using three analyses methods of ML(Maximum Likelihood),MP(Maximum Parsimony),NJ(Neighbor-joining).The results indicate that ITS,LSU,tub2 and rpb2 can obviously distinguish species with high bootstraps values,and bootstraps values from small to large are: tub2 < ITS < LSU < rpb2.This paper recommends tub2,ITS,LSU and rpb2 as DNA barcoding for Gliomastix.A total of 33 strains are identified as 4 species: Gliomastix feline,G.rosegrise,G.murorum,G.polychroma。For phialophora-like strains,phylogenetic analyses were made with combined ITS,LSU and tub2 gene regions or only ITS gene,by constructing multigene and single gene tree,and the result reveals that Phialophora is divided into 16 genera.Three new combinations: Gaeumannomyces zeicola com.nov.,G.graminicola com.nov.,Ramophialophora geniculate com.nov.,and two new records Capronia leucadendri、Fonsecaea multimorphosa are introduced.In order to compare the structural differences between 4 Gliomastix species and 6 Phialophora species,nucleotide sequence alignment analysis of the ITS2 area of these species was conducted and the secondary structure was predicted.The results indicate that the phylogenetic relationships among the species based on nucleotide comparison are mostly identical with the prediction of the secondary structural characters.This highly conservative sequence can be effectively used for species identification and phylogenetic relationship study of Gliomastix and Phialophora.The holotype and ex-type cultures are deposited in the Herbarium of Department of Plant Pathology,Guizhou University(HGUP).