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.
