Phylogenetic Studies of DNA and Morphological Variation in the Subtribe Ecliptinae

族的亚族的系统学研究 向日葵科（菊科），一组约500 - 600种的植物， 美国南部和东部、墨西哥、中美洲和南美洲、非洲 亚洲提出。 该研究将集中在四个主要领域。 问题：主要血统和关系的阐明 在亚族内;澄清亚属分类学的 Verbesina，这是最复杂和分类学上最困难的 亚族的一个属和向日葵族的最大属; 解决一般的关系和亚部落的安置 Verbesian;以及对进化模式和 南美洲的Verbesina辐射。 这些目标将是 主要完成的是收集叶绿体和核 核糖体DNA限制性位点数据，以及染色体和 形态学数据 这些不同数据集的分支分析 将产生一个亚族和最大的属的后代， 向日葵族 这些研究的结果，结合 Heliantheae的cpDNA限制性位点研究（Kim et al. 1990a）将有助于澄清亚部落的限制和关系， 菊科最大的一个族。 此外，在 在Verbesina内的属下水平，由此产生的遗传学可以 然后被用来构建一个现代的亚属分类 属，以及提供了解决重要的基础 地理问题。

Systematic studies of the subtribe Ecliptinae of the tribe Heliantheae (Asteraceae), a group of about 500-600 species of the Southern and Eastern USA, Mexico, Central and South America, Africa and Asia are proposed. The study will focus on four major problems: elucidation of the major lineages and relationships within the subtribe; clarification of the infrageneric taxonomy of Verbesina, which is the most complex and taxonomically difficult genus of the subtribe and the largest genus of tribe Heliantheae; resolution of generic relationships and subtribal placement of Verbesian; and examination of the patterns of evolution and radiation of Verbesina in South America. These goals will be accomplished primarily be gathering chloroplast and nuclear ribosomal DNA restriction site data, as well as chromosomal and morphological data. Cladistic analysis of these diverse data sets will produce a phylogeny for the subtribe and the largest genus in tribe Heliantheae. The results of these studies, combined with recent cpDNA restriction site studies of the ÕHeliantheae (Kim et al. 1990a) will help clarify subtribal limits and relationships in one of the largest tribes of the Asteraceae. Furthermore, at the infrageneric level within Verbesina, the resulting phylogenies can then be used to construct a modern infrageneric classification of the genus, as well as provide a basis for resolving important biogeographical questions.