Morphological And Molecular Phylogenetic Studies Of Dematiaceous Hyphomycetes On Dead Branches From Five Provinces In Southern China

In southern China, ecological environment and structure types are complex and diverse, mainly characterized by tropical and subtropical monsoon climate. Humidity, all of the sampled regions are high humidity and high temperature. Forest coverage rate is high, the surface has accumulated a large number of dead plant residues, the special ecological environment and vegetation inevitably contains a wide variety of dematiaceous hyphomycetes. Therefore, carry out this study to survey the dematiaceous hyphomycetes from decaying wood of southern China have important implications for enriching the species resources of our country and has important significance to protect biodiversity.For a long period, artificial cultivation of dematiaceous hyphomycetes is hard, and the species belong to many different genera, species resources in the genus is difficult to accumulate, so the traditional morphology is still the basis to study this group of fungi, at the same time, we try to accumulate species resources to evaluate genetic evolutionary relationships between morphological similar genera or to test the classification basis at the genus or species level.On the basis of previous studies in our laboratory, a total of 900 specimens were collected from many representative sites in Chongqing, Guizhou, Hainan, Guangxi and Yunnan provinces. The specimens were brought to the laboratory in the sterile plastic bags and incubated in the moist boxes, then examined under the dissecting microscope. From these collections, more than 100 species are obtained, Combine morphological characterictics with molecular data of ITS, LSU, SSU and ?-tubulin,25 taxa are described and illustrated which belong to 11 genera. Among them,5 genera are established,10 taxa are identified as new species,1 species is combined to other genus,14 taxa have been reported from China. The genetic evolutionary relationships are revealed between Acrodictys and morphologically related genera, the index is established. All genera and species are described and illustrated. All specimens examined are deposited in the Herbarium of the Department of Plant Pathology, Shandong Agricultural University (HSAUP) and Mycological Herbarium, Institute of Microbiology, Chinese Academy of Sciences (HMAS).5 new genura:Anacacumisporium Y.R. Ma & X.G. Zhang, Atrokylindriopsis Y.R. Ma 6 X.G. Zhang, Dictyoceratosporella Y.R. Ma & X.G. Zhang, Multicellacrodictys Y.R. Ma & X.G. Zhang and Neoacrodictys Y.R. Ma & X.G. Zhang.10 new species:Neoacrodictys elegans Y.R. Ma & X.G. Zhang, Atrokylindriopsis setulosa Y.R. Ma & X.G. Zhang, Anacacumisporium appendiculatum Y.R. Ma & X.G. Zhang, Dictyoceratosporella cordata Y.R. Ma & X.G. Zhang, Dictyoceratosporella limushanense Y.R. Ma & X.G. Zhang, Mirandina inaequalis Y.R. Ma & X.G. Zhang, Muticellacrodictys obliqua Y.R. Ma & X.G. Zhang, Phaeomonilia guangxiensis Y.R. Ma & X.G. Zhang, Pseudoacrodictys balansae Y.R. Ma & X.G. Zhang, Pseudoacrodictys limoniacea Y.R. Ma & X.G. Zhang.1 new combination:Muticellacrodictys septosporioidea (Matsush.) Y.R. Ma & X.G. Zhang.14 Chinese known species:Acrodictys bambusicola M.B. Ellis, Acrodictys liputii L. Cai & K.D. Hyde, Acrodictys porosiseptata G.Z. Zhao, Acrodictys globulosa (Toth) M.B. Ellis, Acrodictys malabarica Subram. & Bhat, Acrodictys peruamazonensis Matsush., Acrodictys elaeidicola M.B. Ellis, Junewangia sphaerospora W.A. Baker & Morgan-Jones, Junewangia lamma (Whitton, McKenzie & K.D. Hyde) W.A. Baker & Morgan-Jones, Rhexoacrodictys martinii (J.L. Crane & Dumont) G. Delgado, Rhexoacrodictys queenslandica (Matsush.) W.A. Baker & Morgan-Jones, Rhexoacrodictys erecta (Ellis & Everh.) W.A. Baker & Morgan-Jones, Rhexoacrodictys fimicola (M.B. Ellis & Gunnell) W.A. Baker & Morgan-Jones, Pseudoacrodictys deightonii (M.B. Ellis) W.A. Baker & Morgan-Jones.Based on the results of careful analysis, we summarize the following conclusions:1) Taxonomic studies of anamorphic fungi is mainly based on morphological characteristics of the asexual stage. For some species can be cultivated by single spore isolation, we can determined its taxonomic status based on morphological characteristics togenether with phylogenetic analysis.2) The type of conidiomata, the elongated style of conidiogenous cells/conidiophores and conidiogenous pattern are key to distinguish hyphomycetes at genus level; the characteristics of conidiogenous cells, the mode of conidial secession (schizolytic/ rhexolytic) and special features such as euseptation/distoseptation. solitary/catenate are occasionally used as the criteria for identification at generic level; the branching pattern of conidiophores, presence of sterile setae and stroma are also useful to distinguish a few genera.3) Conidial morphology including size, shape, pigmentation, septation, ornamentation and appendage are the basic criteria in distinguishing species. Among related species, the outstanding conidial characteristics are also help with genera circumscribed. The presence or absence, forming sequence and position of septation are also considered as criteria in distinguishing species or genera for different species or genera that have stable differences.4) The analysis of molecular systematics are largely reflect the morphological taxonomic research results, consistent for most time. Thus, combine morphological characterictics with molecular data to study dematiaceous hyphomycetes at the generic and species level is feasible and necessary.