中国糙孢菌目真菌的多样性和分子系统学研究

Trechisporales belongs to Agaricomycetes, Basidiomycota, and accommodates one family, 16 genera and 120 species. Of these species, most are corticioid wood-inhabiting macrofungi. Trechisporales was established according to recent molecular systematics studies, which, however, all aimed to construct the phylogenetic relationships within the whole group of corticioid fungi and referred to only several species of a few of the 16 genera within this order. Therefore, the circumscription of family and genus ranks within Trechisporales is not fully reliable and the relationships among species within a single genus should be further clarified. Morphology-based taxonomy of Trechisporales has been well studied in Europe and North America for years. In China, taxonomic study on Trechisporales is extremely poor, and only 24 species were reported in scattered papers. Moreover, most of the 24 species were identified as new records to China just according to morphological concepts of foreign species. China possesses various kinds of forests, which provide ecological niches for abundant wood-inhabiting fungi. Therefore, many unknown species of Trechisporales could exist there. Given above, this project tries to widely ask for specimens of Trechisporales as loans from herbaria both inside and outside China, and more importantly, to collect specimens and isolate strains of Trechisporales via a series of field trips in famous forest parks and nature reserves all over China. Based on evidence from both morphology and molecular systematics, Chinese specimens of Trechisporales will be properly identified, diversity and distribution of Trechisporales in China will be clarified, and a more natural taxonomic system of Trechisporales will be proposed.

糙孢菌目隶属于担子菌门、伞菌纲，包括1科16属120种，是革菌类群占绝大多数种类的一类大型木生真菌。该目是依据最近的分子系统学研究所建立，但这些研究均是在构建整个革菌类群系统发育关系时涉及到糙孢菌目部分属的少数种类，因此该目下的科属范围不完全可靠，属内种间关系亦有待澄清。欧洲和北美对于糙孢菌目属种的形态分类学研究相对充分。中国糙孢菌目分类学研究极其薄弱，只是零散报道过24个种类，且绝大部分是仅依据国外种类形态概念所鉴定的中国新记录种。我国森林类型多样，孕育着丰富的木生真菌资源，理应存在大量未知的糙孢菌目种类。有鉴于此，本项目拟在广泛借阅国内外馆藏糙孢菌目标本的基础上，重点在全国范围的主要森林公园和自然保护区开展一系列的野外资源调查，采集糙孢菌目标本并分离菌种。结合形态学和分子系统学证据，准确鉴定我国糙孢菌目标本，明确中国糙孢菌目真菌资源多样性及其分布情况，构建糙孢菌目更趋于自然的分类系统。

糙孢菌目隶属于担子菌门、伞菌纲，包括1科16属约120种，全球广布，其中绝大部分种类属于大型木生真菌中的革菌类群。糙孢菌目是依据最近的分子系统学研究所建立的，但相关研究是在构建整个革菌类群系统发育关系时涉及到糙孢菌目部分属的少数种类，因此目下的科属范围不完全可靠，属内种间关系亦有待澄清。欧洲和北美洲对糙孢菌目属种的形态分类学研究相对较为充分，而我国及周边地区的糙孢菌目分类学研究极其薄弱，且绝大部分报道过的种类是仅依据欧美种类的形态概念所鉴定。因此，本项目在全面收集糙孢菌目及相关真菌标本的基础上，以亚太地区研究材料为重点，结合欧美地区相关材料，对糙孢菌目真菌进行了系统性研究。结合多基因系统发育分析、分子钟分析和形态学特征，修订了糙孢菌目的界限，将其中的Sertulicium属和Sistotremastrum属移出糙孢菌目，并建立了涵盖这两属的新目Sistotremastrales和新科Sistotremastraceae；建立糙孢菌目一新属Allotrechispora，并将Boidinella、Litschauerella和Sphaerobasidium三属移出糙孢菌目，其中Boidinella划归回鸡油菌目，Litschauerella和Sphaerobasidium的高阶分类位置未定，但更接近于锈革孔菌目；最终确定糙孢菌目共有1科Hydnodontaceae、12属，即Allotrechispora、Brevicellicium、Brevicellopsis、Dextrinocystis、Fibrodontia、Luellia、Porpomyces、Pteridomyces、Subulicystidium、Suillosporium、Trechispora和Tubulicium，同时对这些科、属进行了简要注解，并给出了全部12属的检索表。发现Allotrechispora属新种1个、新组合种2个；发现Fibrodontia属新种3个；发现Subulicystidium属新种1个；发现Trechispora属新种17个、新组合种5个，将Trechispora yunnanensis移出Trechispora属，给出该属全部81个种的检索表。综上，本项目构建了糙孢菌目更趋于自然的分类系统，增加了对该目物种多样性的认识，为后续相关真菌类群的分类学研究奠定了坚实的基础。