Dissertation Research: Systematics and Floral Morphology Evolution in the Genus Piper (Piperaceae)

9972600马诺斯和哈拉米略研究生亚历杭德拉哈拉米略，在保罗马诺斯博士的指导下，在杜克大学，正在研究大属胡椒的分类学分类（黑胡椒和白色胡椒的属，约100种）。1200种）和花的形态在这个热带组的几个物种的发展。胡椒属植物以灌木、藤本植物和草本植物的形式出现在世界各地的热带森林的林下和树冠层中。虽然单个的胡椒花很小，但该物种在单性和两性形式上表现出广泛的多样性，包括各种类型的完美花，其雄蕊的数量和位置关系不同。然而，花的变化模式还没有被独立测试作为系统发育（或系谱）关系的可靠指标。本研究将着重于核基因和叶绿体基因的DNA序列测定，作为构建植物遗传学框架的证据来源。130种，代表已知的亚属和地理多样性的属，以进一步研究花形态的个体发育（发育）阶段。个体发生的修改，如dioxidase和极端雄蕊减少，将映射到植物基因，以测试花的创新和整个属的多样化之间的关联。系统发育分析也将改善这一大属的亚属和区组分类，并有助于推进改进种级划界。一个更好的理解的进化历史的风笛提供了一个机会，以确定关键的花卉创新的多样化的最大的属的“原始”双子叶植物。

9972600Manos and Jaramillo Graduate student Alejandra Jaramillo, under the direction of Dr. Paul Manos at Duke University, is studying the taxonomic classification of the large genus Piper (the genus of black and white pepper, with ca. 1200 species) and the development of floral morphology in several species of this tropical group. Piper species occur as shrubs, lianas, and herbs in the understory and canopy of tropical forests worldwide. Although individual Piper flowers are minute, the species express a wide range of diversity in unisexual and bisexual forms, including various types of perfect flowers that differ in the number and positional relationships of their stamens. However, patterns of floral variation have not been independently tested as reliable indicators of phylogenetic (or genealogical) relationship. This project will emphasize the DNA sequencing of both nuclear and chloroplast genes as sources of evidence to construct a framework phylogeny for ca. 130 species representative of the subgenera and geographical diversity known for the genus, in order further to study ontogenetic (developmental) stages in flower morphology. Ontogenetic modifications, such as dioecy and extreme stamen reduction, will be mapped onto phylogenies to test the association between floral innovation and diversification across the genus. Phylogenetic analysis will also improve the subgeneric and sectional classification of this large genus, and help advance improved species-level delimitation. An improved understanding of the evolutionary history of Piper provides an opportunity to identify key floral innovations in the diversification of the largest genus of "primitive" dicots.