The Phylogenetic Study Of Diaporthe In Southwest China

The genus Diaponthe is a fungal group including important plant pathogens,some of which can cause significant economic importance,and some are regarded as quarantine diseases as well.These fungal groups are widely distributed throughout the world,especially in tropical and temperate ecosystems.They are important plant pathogens which can cause many kinds of diseases on a variety of plants owing to their not high host-specificity.In order to get a good understanding of Diaporthe diversity in Southwestern China,the specimens were collected from Guizhou,Yunnan,Sichuan,and Guangxi provinces.The morphological and phylogenetic studies are used to identify the species,as well as the diversity study.In our research,we collected specimens from four provinces.After isolation and purification,71 Diaporthe isolates were obtained during 2017 to 2019.After morphological studies and phylogenetic analyses with combined ITS,tef1,tub2 and CAL gene regions,8 new species,10 reported spices are identified,and 20 suspected new species need to be further identified,this indicates that fungi have a wide distribution,rich sources and species diversity in Southwestern regions.New species are Diaporthe millettiae,D.osmanthi,D.guangxinse,D.curcumae,D.cycasis,D.magnoliae,D.discorea,D.rhododendronae;reported species are D.dorycnii,D.viniferae,D.fusicola,D.hongkongensis,D.yunnanensis,D.caulivora,D.pascoei,D.detrusa,D.tectonendophytica,D.melonis.Some isolates were re-inoculated by the Koch’s rule to the leaves to produce identical symptoms as observed in the field.This study detailed the diversity of Diaporthe species in southwestern China,and the relationship between this fungal group and the hosts.Our study has an important value in the disease control and resources application.