title: A new species of Scytalidium causing slippery scar on cultivated Auricularia polytricha in China.
abstract: Slippery scar is one of the most destructive diseases encountered in the cultivation of Auricularia polytricha (hairy wood ear); however, the identity of the pathogenic agent has remained uncertain. This study was designed to identify the causative pathogen of slippery scar in A. polytricha and to investigate the taxonomic classification of the pathogen by morphological observations, in vivo pathogenicity tests, and molecular evidences of ITS and RPB2 sequences. The results showed that the pathogen was a new Scytalidium species, here named Scytalidium auriculariicola. Scytalidium auriculariicola was characterized by its rapid growth rate, the catenate conidia of variable size, and the pale brown to brown chlamydoconidia. Phylogenetic analyses based on internal transcribed spacer regions and RPB2 sequences on the pathogen isolated and related species supported that S. auriculariicola was a true Scytalidium species. It was congeneric with and close to Scytalidium lignicola, the type species of Scytalidium. However, it differed from the latter species in the size of conidia, 33 different nucleotide bases in ITS sequences and 30 different nucleotide bases in RPB2 sequences.
authors.affiliation: Key Laboratory of Bio-resources and Eco- environment Ministry of Education, Chengdu, Sichuan, China; Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, China.
authors.forename: Weihong
authors.initials: W
authors.lastname: Peng
authors.forename: Xiaolan
authors.initials: X
authors.lastname: He
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiaojin
authors.initials: X
authors.lastname: Ye
authors.forename: Dinghong
authors.initials: D
authors.lastname: Jia
authors.forename: Yong
authors.initials: Y
authors.lastname: Guo
authors.forename: Bingcheng
authors.initials: B
authors.lastname: Gan
authors.forename: Chao
authors.initials: C
authors.lastname: Zheng
authors.forename: Zhirong
authors.initials: Z
authors.lastname: Yang
authors.forename: Qun
authors.initials: Q
authors.lastname: Sun
mesh_terms: D001203:Ascomycota / Q000145:classification* / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D001487:Basidiomycota / Q000502:physiology*; D002681:China; D016000:Cluster Analysis; D004271:DNA, Fungal / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D056265:Microbial Interactions; D008969:Molecular Sequence Data; D010802:Phylogeny; D012319:RNA Polymerase II / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D004271:DNA, Fungal; D021903:DNA, Ribosomal Spacer; D012319:RNA Polymerase II
keywords: Koch's postulation; cultivated mushroom; internal transcribed spacer regions; protein-coding gene