Studies On Taxonomy Of Rhytismataceae On Tanoaks From Mt Huangshan And Phylogenetic Relationships Of Lophodermium And Terriera

Mt Huangshan, which is situated in southern Anhui Province of China, is a suitablehabitat for many species of Rhytismataceae, because of warm climate, abundant rainfalland a great diversity of plants. Species of the family, which was collected from leaves oftanoaks from Mt Huangshan, were systematically studied with the most novelty andadvanced fungal classification technology and poly-character integrated taxonomy meanswhich are based on the characters of morphology, individual development, ecology anddistribution, etc. At the same time, rDNA-ITS sequences of partial species ofLophodermium and Terriera were amplified, determinated and phylogenetic studied withother related sequences in GenBank.Some samples were identified and classified according to the taxonomic principles ofDarker (1967) and other academics. Eight species in three different genera ofRhytismataceae were identified. Among them, Coccomyces lithocarpi and Terriera.coacervata are new species, T. illiciicola is a new combination, and other species, i.e. C.delta, C. huangshanensis, C. mucronatus, Lophodermium agathidis, and T. minor, arealready known for China. This paper provides descriptions, hosts, distribution anddiscussions with close species in detail for these species. The two new species areillustrated as well as a dichotomous key for the eight species.rDAN-ITS region of29strains of Lophodermium and Terriera was amplified andsquenced, and comparative analysis with7related ones in GenBank. A phylogenetic treewas constrcuted based on these sequences, using Soleella chinensis as an outgroup. Theanalysis results showed that the interspecific relation of Rhytismataceae were interrelatedwith their hosts. The members of Rhytismataceae from conifers can separated from thosefrom broad-leaved trees. Affiliation between the two genera is more relatived. Species ofLophodermium are parasitic on conifers and broad-leaved trees, while species of Terrieraare mainly parasitic on broad-leaved trees. In morphology, the latter is different in theabsence of lip cells, in the extension comprising strongly carbonized tissue with no obviouscellular structure, in the excipulum closely adhering to sides of the covering stroma, in thesubhymenium with a region of near-colorless, hyaline, textura prismatica at the edge of theascoma, and in the paraphyses sometimes swelling or branching at the apex andagglutinating to form a epithecium. The ITS sequence length of the members ofLophodermium (435-444bp) is shorter than that of the members of Terriera (453-460bp),but G+C content of the members of Lophodermium (51.9%) is more than that of the members of Terriera (49.0%). In phylogenetic tree, the species of Lophodermium fromconifers and the species of Terriera are sharply classified into two independent groups, andthe species within the genera are also shraply classified into smaller groups. The results areconsistent with the classification based on phenotypic characters, and proves that the hostcan affect the interspecific affiliation greatly.The modern molecular methods, which are used on taxonomy of fungi, can providessupplementary evidence and proves the correctness for traditional morphological taxonomy.At the same time, the reference basis is provided to build a more scientific and reasonableclassification system of Rhytismataceae.