广义石山苣苔属（苦苣苔科）系统发育重建和分类学修订

Petrocodon sensu lato (Gesneriaceae) is distributed predominantly from southwestern and southern China to central and eastern China, to the northern edge of Indo-China Peninsula. The first revision in 2011 to original monotypic genus, Petrocodon sensu stricto, helped it to become a small genus containing at least 33 species and one variety (Petrocodon sensu lato) (most of them endemic). Previous evidences of molecular systematics showed that Petrocodon sensu lato is monophyletic. However, it is not clear about the species number and the actuality of this genus resource so far. At the same time, due to the complicated variation pattern of morphological characters of Petrocodon sensu lato, and low resolved phylogenetic relationship by using few DNA regions, together with the absence of taxonomic revision and phylogeny at generic level, the genus faces too many taxonomical problems at present including species delimitation and unresolved phylogeny within Petrocodon sensu lato. Therefore, this study will carry out the phylogenetic research based on consulting the type specimens, comprehensive sampling of living materials at population and special level by lots of field works and laboratory experiments. We will select plenty of DNA regions to jointly reconstruct the phylogenetic tree. The aims of this project are to evaluate the taxonomic value of chromosome number, macro- and micro-morphological characters, to study evolvement rules and variation patterns of morphological characters, based on molecular systematics. Then we will combine the aforementioned data and evidences to make a revision, to discuss interspecific genetic relationships, to subdivide the infrageneric classification of the genus, to reconstruct the ancestral distributed area to explain and discuss the origin, evolution and spread of this genus from the aspect of biogeographical history. This is would ultimately solve those taxonomical problems and troubles of Petrocodon sensu lato. This project will lay the foundation for further study on biogeography and conservation biology, and will also provide a reliable reference and scientific basis for the horticulture and utilization of plant resources of Petrocodon sensu lato to serve the local economic development.

广义石山苣苔属（苦苣苔科）主要分布于我国西南华南，扩展至华中华东，南延至中南半岛北缘。2011年对本属的梳理使其由单型属演变为今天包含33种1变种的小属，多为地区特有种。前期分子系统学证据表明本属为单系类群，但由于物种间形态特征变异复杂，所用片段无法获得高分辨率系统发育关系，因而未能开展进一步的分类修订和系统学研究，一些分类学问题，如属内种间演化关系未明，物种界定等亟待解决。本研究从模式标本出发，以居群概念为指导，实现属内世界范围内所有物种的全面取样，通过大量野外与室内试验开展系统发育研究；选取多个DNA片段联合构建系统发育树，并在此系统发育框架下：①评估宏观微观形态性状、染色体数据等的分类学价值，研究其形态性状演化规律；②联合上述证据进行分类修订、探讨属下种间亲缘关系、进行属下分类系统划分；③重建祖先分布区来探讨本属的起源、演化、散布途径和方式。最终解决目前本属存在的分类学和系统学问题。

广义石山苣苔属Petrocodon Hance自2011年被修订以来，被认为是一个自然类群且与报春苣苔属Primulina Hance互为姐妹类群。项目在前期研究的基础上，以居群概念为指导，开展了大量工作：（1）开展了针对我国华南、西南和部分华东地区的野外调查，但境外合作因疫情的关系未能达成预定目标；（2）利用6个DNA片段联合构建了高分辨率和高支持率的系统发育框架，为广义石山苣苔属的系统学研究奠定基础；（3）完成广义石山苣苔属植物45种1变种通用DNA条形码数据库（ITS+psbA-trnH+matK+rbcL）初步构建，为后续深入地开展物种鉴定和保护研究奠定了良好的基础；（4）对我国石山苣苔属各物种的地理分布有了清晰的认识，开展了石山苣苔属的潜在适生区特征及其环境驱动因子的研究，并将其地理分布格局用于指导资源利用及保护；同时以广西为范例开展了石山苣苔属植物的IUCN濒危等级评；（5）发现并发表石山苣苔属新种10个，石山苣苔属植物省级分布新纪录4个，极大地丰富了对石山苣苔属生物多样性和地理分布的认知，使世界石山苣苔属植物增加至45种1变种；（6）结合形态学、孢粉学、细胞学、分子生物学等技术手段，基本确定了石山苣苔属的界限，解决了广义石山苣苔属植物中疑难种、混淆种的界定问题；（7）资助学生完成硕士毕业论文和相关论文。（8）相关专著初稿，《中国石山苣苔属植物》，已完成并与出版社签署合同，拟于2023年下半年出版。本项目的开展为进一步研究石山苣苔属的物种形成机制及其他相关研究奠定了基础。