The evolutionary history of Hypericum (Hypericaceae) with special emphasis on sect. Hypericum - Biogeography, character evolution, ecological shifts, and age estimations

金丝桃属植物为金丝桃科金丝桃属植物，由460多种乔木、灌木和草本植物组成，分布于北半球温带地区、热带高海拔生境、南美洲南部(1 sp.)和澳大拉西亚(2种)。它是100个最大的被子植物属之一，也是为数不多的，如果不是唯一的，由于诺曼·罗布森博士(伦敦自然历史博物馆)50年的工作而几乎完成阿尔法分类的属之一。在Hypericum中，目前可以识别32个部分。然而，到目前为止，还没有对该属的形态特征进行正式的分支分析或扩展的分子系统学方法来划分该属的自然单位(即单系群)。在拟议的项目中，将采用嵌套的Hypehcum系统发育分析方法。与自然历史博物馆合作，将对整个属进行全面的骨干系统发育研究，分析250个物种的nrDNA ITS序列、单拷贝核基因和合适的叶绿体DNA区域。通过这一分析，我们将测试金丝桃组是否为单系群，如果不是，则界定该属内的新的单系实体。对于与贯叶连翘(Common St.John‘s Wort)较近的亲缘关系，即金丝桃组(可能在一个新的范围内)及其亲缘关系，将进行详细的系统发育关系分析，包括每个物种几个个体，并应用系统发育和种群遗传学分析方法。对于这一组，将使用核ITS和单拷贝基因数据以及叶绿体数据。在系统发育的基础上，我们将重建特征进化(例如，草本与木质习性、胶囊与浆果、染色体数量)、历史生物地理(包括热带和温带生境之间的变化导致的生态位变化、殖民方向、分离的年龄)、药用或可用次生化合物(金丝桃素、利尿剂)的分布以及金丝桃属无融合生殖的进化。

The genus Hypericum (St. John's wort; Hypericaceae) consists of over 460 species of trees, shrubs and herbs, occurring in temperate regions of the Northern Hemisphere, in tropical high elevation habitats, and with few species, in southern South America (1 sp.) and Australasia (2 spp.). It is one of the 100 largest angiosperm genera and one of the few, if not the only, where the alpha taxonomy is nearly completed due to 50 years of work of Dr. Norman Robson (Natural History Museum, London). Within Hypericum 32 sections are currently recognized. However, no formal cladistic analysis of morphological characters or an extended molecular systematic approach was conducted up to now to circumscribe natural units (i.e. monophyletic groups) of the genus. Within the proposed project a nested phylogenetic analysis approach of Hypehcum will be done. In cooperation with the Natural History Museum a thorough backbone phylogeny of the entire genus will be conducted, analyzing -250 species with nrDNA ITS sequences, a single copy nuclear gene, and a suitable chloroplast DNA region. With this analysis we will test if the sections of Hypericum are monophyletic groups and, if not, circumscribe new monophyletic entities within the genus. For the closer relatives of H. perforatum (Common St. John's wort), i.e. section Hypericum (probably in a new circumscription) and close allies, a detailed analysis of phylogenetic relationships will be done, including several individuals per species, and applying phylogenetic and population genetic analysis methods. For this group nuclear ITS and single copy gene data as well as chloroplast data will be used. On the basis of the phylogenies we will reconstruct character evolution (e.g., herbaceous vs. woody habit, capsules vs. berries, chromosome numbers), historical biogeography (including niche shifts due to changes between tropical and temperate habitats, colonization directions, age of disjunctions), distribution of medically used or usable secondary compounds (hypericin, diuretics), and the evolution of apomixis within Hypericum.