Studies On Species Diversity Of Rhytismataceae On Camellia Spp. From The Chiinese Mainland And ITS Sequence Analysis Of Lophodermium On Broad-leaved Trees

Taxonomy and species diversity of Rhytismataceae on Camellia spp. from the Chinese mainland were systematically studied with the advanced fungal classification system and poly-character integrated taxonomy method which is based on the characters of morphology, ontogeny, ecology and biology etc. At the same time, rDNA-ITS sequences of many strains of Lophodermium were amplified and sequenced, and13sequences were obtained finally. A phylogenetic tree of these strains was constrcuted by PAUP, using maximum parsimony method, which is on the basis of these13sequences and other3related sequences in GenBank and Phenotypic character. The relationships of Lophodermium in interspecies and intraspecies were discussed.Specimens on Camellia spp. from the Chinese mainland from own collections and the Herbarium of Forest Fungi of Anhui Agricultural University (AAUF) were examined and classified according to the taxonoic principles of Darker, Cannon&Minter, Johnston, Spooner and Kirk et al. Six species in five different genera of Rhytismataceae were studied, including Bifusella camelliae, Coccomyces sinensis, Hypohelion durum, Lophodermium jiangnanense, L. sinense and Terriera camelliae. Among them L. sinense is described as a new species, Terriera camelliae is a new combination, while Bifusella camelliae, Coccomyces sinensis, Hypohelion durum and L. jiangnanense are species already known for China. Morphological descriptions, host range, habits, distributions, discussions as well as a dichotomous key were provided for all species. Brief Latin diagnoses and illustrations were also provided for the new species. All examined specimens are deposited in the Herbarium of Forest Fungi of Anhui Agricultural University, China (AAUF).Aphylogenetic tree of Lophodermium on broad-leaved trees was constrcuted based on sixteen ITS sequences of six species, and Hypohelion durum (GU367909*) was selected as outgroup. The phylogenetic tree included2clades. Lophodermium sp., L. implicatum, L. jiangnanense and L. agathidis composed Clade I with64bootstrap support values and76.69%identity. Two strains of L. tiantangzhaiense formed Clade II with100bootstrap support values and97.76%identity. Clade I involved3subclades: A, B and C. Two Lophodermium sp. formed subclade A with99boostrap support values and89.52%identity. L. implicatum and L. jiangnanense composed subclade B, which had98boostrap support values and93.68%identity. Ten L. agathidis strains were clustered together and formed subclade C with98bootstrap support values and81.28%identity. Three conclusions were obtained from the analysis of the phylogenetic tree. Firstly, Interspecific relationships of Lophodermium on broad-leaved trees are not related to their hosts. Secondly, Origin and hosts have great impact on Intraspecific genetic diversity, the strains which have the same origin or close hosts are clustered together firstly. Thirdly, position of embedding, development of the covering and basal stroma, the shape of asci and paraphyses have important significance in taxonomy of Lophodermium in the species level.